Garfield County adopts the 2018 IECC

June 16, 2023

Garfield County has adopted the 2018 International Energy Conservation Code (IECC) in compliance with a 2019 state law requiring local governments choose one of three iterations of the IECC in its building code. The 2018 version of the IECC features minor changes in insulation values and requires a blower door test to be performed on all new homes to check air-sealing and ventilation.

John Plano, chief building official for Garfield County Community Development, told the Board of County Commissioners that the state has mandated that all local governments select one of three energy codes (IECC 2015, 2018, or 2021) to abide by no later than July 1, or be required to adopt the 2021 version. The county had been operating under the 2009 IECC.

“The code cannot be changed or amended to make it less stringent,” he explained to the board. “If we change or amend any building code at any time after July 1, 2023, we will have to adopt the 2021 or most current code, which will be more onerous than the one we currently utilize.”

The 2021 IECC requires that new homes be pre-wired for future solar photovoltaic or solar thermal installations, high-efficiency electric appliances in mixed-fuel buildings and charging of electric vehicles, potentially increasing building costs.

The county reached out to local architects, builders, and citizens in May to gather input and provided a training session for interested members of the community.

The board approved repealing the 2009 IECC and adopted the 2018 IECC unanimously, 3-0.

“We have very little choice in the matter. This was required due to changes in the law,” added Commissioner John Martin. “Stay tuned for more changes to the energy, building, ventilation, and insulation codes, and on and on. Every code we deal with will be affected.”

We do that…

Please give us a call and we can help navigate the process in the most cost-effective way. And optimize your construction for performance.

Jump to Energy Conservation Code Hub for; the western slope of Colorado; Aspen, Telluride, Mountain Village, Town of Snowmass Village, Basalt, Carbondale, Glenwood Springs, Pitkin, Eagle and Garfield Counties…

City of Glenwood Springs Energy Conservation Code

On June 6, 2022, the City will require building permits to use the 2021 editions of the International Building Code, International Residential Code, International Mechanical Code, International Existing Building Code and International Energy Conservation Code.

 

We do that…

Please give us a call and we can help navigate the process in the most cost-effective way. And optimize your construction for performance.

Jump to Energy Conservation Code Hub for; the western slope of Colorado; Aspen, Telluride, Mountain Village, Town of Snowmass Village, Basalt, Carbondale, Glenwood Springs, Pitkin and Eagle County…

Aspen’s 2021 Energy Code Adoption

Aspen’s adoption of the 2021 I-codes is heavily modified. This article looks only at the energy conservation parts of the adoption. And this is just a summary of the most perennate changes that may influence design.

Link here to the actual adoption documents… 

Four compliance paths:

  1. Prescriptive/Building UA/R-value alternative +23% including all additional mandatory requirements
  2. Performance +5%
  3. ERI +5% (2021 ERI 50.35)
  4. Existing building, Chapter 5

Notable modifications to mandatory residential energy requirements:

  • Prescriptive envelope requirements: R60 roof, R40 walls, R20 basement walls, windows max U-factor of .26 (inert gas with uncapped breather tube units don’t count)
  • Max 30% glazing to wall area (garage and sunroom glazing counts)
  • 1.5 ACH50 air leakage
  • ERV/HRV and flow testing required
  • Duct leakage testing was stricken for the Prescriptive path
  • Special provisions to avoid Thermal bridging
  • Commissioning
  • Sign Up for Building IQ benchmarking program (data gathering)
  • Sensible electric ready provisions
  • New triggers for energy efficiency requirements for alterations

Commercial Energy Changes:

  • Prescriptive, 2019 ASHRAE 90.1 or Performance
  • Envelope infiltration testing; Dwelling and sleeping units .30 CFM50 per square foot of envelope, everything else .40 CFM75 per square foot of envelope.
  • ventilation flow testing
  • Enhanced envelope, especially walls
  • EV requirements
  • Electric ready provisions
  • New triggers for energy efficiency requirements for alterations

Expanded REMP:

  • Heat tape, gas fireplaces, outdoor heaters will now need to be offset
  • Gas fireplaces will be required to be sealed combustion
  • 200,000,000 BTU/year cap for all exterior energy
    • Snowmelt 2414 ft2 OR,
    • Pool 603 ft2 OR,
    • Spa 466 ft2 OR,
    • Heat tape 3125 linear feet of typical heat tape

Incentivize All-Electric New Construction:

  • Expedited Permit Review
  • AC units must be heat pumps

A practical example:

What if a project needs to break with the Prescriptive path? For instance, how can a house go about complying with more than 30% glazing? The project would be forced to try and comply by using either the Performance Path or the ERI (Energy Rating Index) Path.

Minimum Performance goal would be…   2021 Building UA +23% & 72% of Energy costs

Minimum ERI goal would be…                   2021 Building UA +15 % & ERI 50.35 – PV

Both of these goals would have to be achieved without help from PV solar.

 

We do that…

Please give us a call and we can help navigate the process in the most cost-effective way. And optimize your construction for performance.

Jump to Energy Conservation Code Hub for; the western slope of Colorado; Aspen, Telluride, Mountain Village, Town of Snowmass Village, Basalt, Carbondale, Glenwood Springs, Pitkin and Eagle County…

Designing for Net Zero

or just a great HERS / ERI score.

 

It’s not easy to show energy code compliance in climate zones 6 and 7. Especially if you’re working in a jurisdiction that has adopted above-code requirements. Designers here’s an exercise to help get your design on its way to IECC compliance and beyond. On your next project, before starting your typical design process, rough out a schematic design, but forget all clients wishes, ARC guidelines, height limits, etc. and design for energy conservation by substituting the following parameters…

Envelope

  1. Make the thermal envelope a simple, regular volume.
  2. Share assemblies with other structures, when possible, but make that party assembly very airtight.
  3. Follow the prescriptive code for air barriers and insulation levels.
  4. Maximum 20% glazing; 20-30% glazing; plan for really, really good windows, over 30% plan for great triple-pane windows.
  5. Put as much of the insulation on the outside of the assembly as you can, or frame with Efficient Framing techniques or use alternate techniques that reduce thermal bridging like; ICFs, SIPs, Larson trusses, adobe, strawbale, etc.
  6. Make the roof within 20° of optimal pitch (10:12 to 14:12) and orientation (160°-200° south) for solar, free from obstructions and penetrations.
  7. Use passive solar heating techniques when possible; insolation managed by proper overhangs and low-e coatings on glazing.

Equipment

  1. Plan for no gas or propane, all electric house.
  2. Use no snowmelt.
  3. Locate the mechanical room, in the core of the house, minimize distribution runs. Give plenty of room to equipment for service. Easy access; no hatches, ladders or crawling.
  4. Locate the outdoor side of the heat pump equipment. Protected from snow and ice.
  5. Don’t use site-built forced-air ductwork if you can avoid it. Radiant or ductless preferred. If not, don’t combine ductwork with garages, ventilated attics or ventilated crawl spaces. Insulate it and seal it very well.
  6. Plan for a stand-alone occupant ventilation system, with occupant controls and easy access for filter cleaning; not in a crawlspace or attic. Ducting this is okay.
  7. Heating; use GSHP (ground source heat pump) if you can. If not, use ASHP (air source heat pump) and passive heating techniques.
  8. Cooling; skip it altogether if you can. If not, use ASHP, evaporative and passive cooling techniques.
  9. Hot water; use thermal solar per-heat if you can. If not, use HPWH (heat pump water heater). Ducting this is okay.

Electric

  1. Use no heat tape.
  2. Use ENERGY STAR appliances. Keep refrigeration loads as low as possible. Induction range and convection oven.
  3. Plan for low flow plumbing fixtures and fully insulated lines.
  4. Plan for DWHR (drain water heat recovery)
  5. If hot water runs are still long enough to require recirculation, use a smart pump with occupant sensors in the bathrooms and a temperature sensor to control the pump runtimes.
  6. Maximize the PV array size.

Designers: Now you have a schematic design optimized for potential energy conservation. As you move on to your typical design process, keep this design in the background. Know that the more your design develops away from the energy conservation architype, the harder it may be to reach specific performance goals.

Note to Structural Engineers: Your challenge is to help the Architects keep as much steel and wood out of the thermal envelope as possible. Support several inches of Continuous Insulation, even behind stone veneer. Keep the foundation completely covered in insulation, even at patios, doors and behind stone veneer.

Note to Mechanical Engineers: Your challenge is to help the Architects reduce all equipment loads, reduce runs and maximize efficiency. Investigate new technology and equipment and learn how to work with it. And help us all reduce a house’s dependence on gas.

Successful transition to the 2021 IECC

What do we need in place to ensure a successful transition to the 2021 IECC?

Designer and plans examiner education

Architects, mechanical and structural engineers need to be taught high-performance construction techniques. An IECC compliance sheet needs to be created and submitted with Construction Documents. This will help front-load the submittal documents with a more developed mechanical system, air sealing details and specifications. Plans examiners need to learn how to recognize energy conservation issues from drawings a flag them for correction before permit issuance. Once something like a weak party wall assembly is permitted, we’re on the defense for the rest of the game.

General and subcontractor education

Contractors need to know what passing work looks like, preferably before they fail an inspection. The half-dozen raters in the valley cannot be the sole education force for thousands of contractors in the valley. GCs need to know how to interact with a rater; what to include them on, what do they need to see, when to call, etc. Subcontractors need supplemental training on ERV installations, air sealing, Radon barrier installation, etc. New technicians need to be trained on heat pump equipment. I don’t believe there are nearly enough qualified people to install all of the heat pump systems we need to install in the near future. And if it is not done perfectly, the equipment won’t live up to its potential.

Homeowner education

Homeowners need to left with a document that explains how to work the house. Most homeowners seem to be clueless about how to operate an ERV for example. If a homeowner never adjusts the ERV flow or disables it completely, or never changes the filter- we may have done more harm than good in the end. Is the filter replacement schedule being posted? Outdoor reset sensors are now required- are the reset temperature curves being programed before the occupants move in?

Product availability

Builders tend to use the products that the local suppliers carry. We need to start building with products that are not typically stocked in the valley to my knowledge. Specifically I am thinking of items like; airtight electrical boxes, drywall clips, HPWHs (heat pump water heaters), small disposable spray foam kits, liquid flashing, high-performance ERVs and ventilation controllers, vapor-retarding latex primer, etc. Somehow, we need to lobby all of the hardware stores and lumber yards to consistently stock these essential products before significant demand is here.

Enhanced inspection schedule

Rater inspections need to added to inspection checklists, far too many projects go uninspected simple because Raters are not notified of the construction schedule. Ratings only technically require two field inspections, but the reality is that two is not enough. Additional inspections should be required.

  1. Pre-test ducted systems at rough-in, prior to insulation, using 2021 IECC standard, even if all ductwork and equipment is in “conditioned” space.
  2. Blower Door & IR Camera at rough-in, post spray foam in roof and walls, but prior to installation of blown-in or batt insulation. If the home has a vented attic, do visual walk-thru with insulator to identify additional air sealing required, then use Blower Door: 1) As soon as drywall ceilings are hung and fire taped, but prior to hanging drywall on walls. Or 2) As soon as all the drywall is hung, finished, and painted; but before any cabinets or trims are installed.
  3. Insulation Inspection when all insulation is complete

Rater-Building Department coordination and cooperation

Raters and Building Inspectors should have a clear understanding of who is checking for what. In the course of rating a house, we check and test a multitude of things; insulation installation quality, infiltration rate, ventilation rate and watt draw, duct leakage rate, pipe insulation, etc. Typically, JHAs ask me only for a certificate and a blower door test report. Getting an infiltration report without a ventilation report, really doesn’t give you the whole story. So far, ventilation is often being done fairly poorly in the field. There is massive confusion between occupant ventilation, crawlspace ventilation, spot ventilation and make-up air supply. I’m afraid we may see an epidemic of mold erupt in our valley in the near future. And lung cancer caused by Radon.

If the JHA does not ask me for the reports, then I assume they are doing those tests and inspections themselves, or they have a departmental policy not to enforce those parts of the IECC.

Final inspection, confirmed rating certificate and CO

Raters are often unmercifully pressured to cough up a certificate immediately at final. Raters need to have a complete, finished house to do our final inspection and test out; PV on the roof, ERV commissioned, every last piece of pipe insulation installed, door handles on and trades out of our way for testing. After our inspection, it takes a day to update the model and submit all of my paperwork. The it takes a day or two for the Rater to get the final certificate from their provider and transmit it to the General Contractor. GCs need to build this time into their schedule, it is not an instantaneous process.

Basalt Colorado’s energy conservation code requirements

The Town of Basalt, Climate Zone 6, is currently on the 2021 IECC (International Energy Conservation Code).

Link to Town Building Department website…

The 2022 SBR Amendment took effect on October 20th, 2022.

The full SBR Ordinance can be found here:
SBR 2022 Amendment_Section 18-23 Ordinance

SBR 2022 Amendment and Beneficial Electrification Requirements
Require buildings to be energy efficient, electric-ready, install renewables and provide energy storage area in order to meet the Town of Basalt’s climate goals.

List of Major energy requirements of the SBR:

1. Renewables

  • Type I Construction: New residential buildings shall be required to install 3 watts per SF of conditioned floor area OR 25% of the annual energy use with on-site renewable energy.

Exceptions:

    • 2 watts per SF (or 15% of the annual energy use) of renewables are required if the building is completely electric.
    • Additions 500 SF and greater, remodels classified as a Level 3 remodel, in which the impacted floor area of the remodel is more than 50% of the conditioned floor area AND is 750 SF or greater, 2.0 watts per SF for a dual fuel house or 1.5 watts per SF for all-electric of solar will be required on the building, for the entire conditioned floor area.
  • Type II Construction: New commercial buildings shall be required to dedicate 40% of the roof area to PV as a solar-ready zone and utilize 25% of their annual energy budget with on-site renewable energy.

Exceptions:

    • Only 15% renewables are required if the building is all-electric.

2. Beneficial Electrification and Storage

  • Battery-Ready, Electric-Ready, Solar-Ready and EV-Ready required for both Type I and Type II Construction; EVCapable for Type II Construction

Exemptions:

    • Level 1 & 2 Remodels
    • Level 3 Remodels that impact < 750 SF (Type I) or < 2000 SF (Type II)
    • Additions less than 500 SF
      • Battery-ready: Show on the construction documents where the battery system would be installed and make sure that minimum clearances are achieved per the International Fire Code requirements, along with necessary electric infrastructure to accommodate the storage system and ensure that it is protected by potential damage by vehicles, etc. The minimum required space is 18” from wall and a minimum area of 2’x4’ dedicated for this future use.
      • Electric-ready (with electrical service reserved space): All systems shall be pre-wired for transition to electric. This includes the water heater, clothes dryer, stove, and HVAC system. A dedicated minimum 125-volt, 20-amp electrical receptacle that is connected to the electric panel with a 120/240 volt 3 conductor, 10 AWG copper branch circuit, shall be provided within 3 feet from each gas or propane water heater, clothes dryer, stove and HVAC system, accessible with no obstructions. A single pole circuit breaker space must be reserved in the electrical panel adjacent to each circuit breaker for the branch circuit and labeled with the words “FUTURE 240V USE.”
      • Electrical service reserved space: For each of the additional receptacles, the main electrical service panel shall have a reserved space to allow installation of a two-pole circuit breaker for future electrical energy storage system installation This space shall be labeled “For Future Electric Storage.” The reserved spaces shall be positioned at the end of the panel that is opposite from the panel supply conductor connection. Any electrical energy storage system that is installed shall meet all requirements of the IFC, Section 1207.
    • Solar-ready: On the construction documents showing proposed location of solar (and square footage) on the roof and all mechanical / plumbing penetrations that will go through the roof. Also identify the orientation (Azimuth) and inclination of the proposed array. A metal conduit for the DC wire running from the array to the inverter and from inverter to electrical service panel is required. Install a dedicated circuit breaker in the electrical service panel. Note that the structural drawings shall account for this additional load.
      • Mandatory Solar: Show on the drawings the required amount of on-site renewables. This will be calculated for you in the REMP Calculation Spreadsheet, as the actual production will be impacted by the orientation and azimuth (tilt).
    • EV (Electric Vehicle)- Ready Space(s): Show these spaces as defined in the Definitions on the electrical and architectural drawings. A designated parking space that has a full circuit installation of 208/240-volt (or greater), 40-ampere (or greater) panel capacity, raceway wiring, receptacle and circuit overprotection devices to allow for the future installation of EV Supply Equipment (EVSE). The receptacle or junction box shall be located in close proximity to the proposed location of the EV parking space.
  • Type II Construction – Electric Vehicle Supply Equipment (EVSE) Installed Space: A designated parking space with dedicated electric vehicle supply equipment capable of supplying a minimum 40-amp, dedicated circuit rated at 208/240 Volt from a building electrical panel.
    • If required parking is 1-9 spots, they need to provide 1 EVSE Ready Outlet spot,
    • if it is 10-19, they need to have 1 Level 2 Charging station installed, and 1 EVSE Ready Outlet spots,
    • if it is 20 or over, they need to have 1 level 2 EV charging stations for every 20 spots and 1 EVSE Ready Outlet per 20 spots.

3. Home Energy Rating System- Required. (HERS)

  • Type I Construction – A HERS 40 score is mandatory for houses over 2,000 sf. A REScheck compliance with envelope 5% greater than code minimum is an option for homes less than 2,000 SF

Exception:

    • A HERS rating of 45 may be allowed in al-electric houses.

4. Exterior Energy

  • There has been a REMP Calculator Spreadsheet made for the Town that will calculate the required solar based on the orientation and azimuth (tilt) of the array. The exterior energy uses such as snowmelt of exterior heaters, the required fee a/o offset is dependent on the type of construction, amount of exterior energy use and the efficiency of the equipment serving it. There is a tab on the spreadsheet for “RREMP,” which is residential and “CREMP”, which is commercial.

5. Existing Buildings and Alterations

  • Type I Residential:
    • IEBC (International Existing Building Code) Level 2: Level 2 alterations per the IEBC shall be defined as projects that utilize reconfiguration of space, add or delete doors a/o windows, reconfiguration or extension of any system, install of additional equipment.”. Level 2 alterations shall be required to obtain an energy assessment by a licensed third party assessor. Along with the energy assessment, a baseline blower door test shall be done with a final blower door resulting in air sealing with 15% improvement in ACH or achieve a 3.0 ACH 50., whichever is less.
    • IEBC (International Existing Building Code) Level 3: Level 3 alterations shall be defined as projects that entail alterations to 50% or more of the conditioned floor area. Level 3 alterations shall be required to obtain energy assessment by a licensed third-party assessor. Along with the energy assessment, a baseline blower door test shall be done with a final blower door resulting in air sealing with 15% improvement in ACH or achieve a 3.0 ACH 50., whichever is less. The electric-ready and solar requirements are required for Level 3 remodels that impact 50% or more of the conditioned floor area AND are greater than 750 SF.
  • Type II – Commercial:
    • All buildings over 20,000 sf are required to get Energy Assessment and have data entered for benchmarking and entry into Energy Star Portfolio Manager per the State of Colorado requirements.
    • Any Level 2 Alterations are required to get an Energy Assessment including a baseline blower door test + final blower door resulting in air sealing with 15% improvement in ACH
    • Any Level 3 Alterations are required to get an Energy Assessment including a baseline blower door test + final blower door resulting in air sealing with 15% improvement in ACH and required to provide renewables per new construction requirements and meet electric-ready requirements of code.

 

REMP (Renewable Energy Mitigation Program)

Basalt has a REMP (Renewable Energy Mitigation Program) that engages anytime exterior uses of energy are used like; snowmelt, pools spas and garages. REMP fees are offset by renewable energy production, fee-in-lieu, or a combination of the two.

SBR (Sustainable Building Regulations)

Link to SBR adoption language…

 

Residential Type I (single-family)

Link to Excel worksheet…

Points are determined under one of four compliance paths; prescriptive, performance, Net Zero Energy Ready or LEED for Homes.

 

Commercial Type II (multi-family and commercial)

Link to Excel worksheet…

Most likely will require at least a COMcheck report for permit application submittal.

 

We do that…

Please give us a call and we can help navigate the process in the most cost-effective way. And optimize your construction for performance.

Jump to Energy Conservation Code Hub for; the western slope of Colorado; Aspen, Telluride, Mountain Village, Town of Snowmass Village, Basalt, Carbondale, Pitkin and Eagle County…

Energy Rating adoption ground rules

If your jurisdiction is adopting the IECC, and if you expect projects to use the ERI path, chapter 406, for energy conservation compliance. Or possibly you are looking to modify the rules or goals to accelerate the energy-efficiency or carbon reduction goals of your community? Then there are a few ground rules you should establish ahead of time, so everybody is on the same page.

Raters need to know exactly what was adopted, how special cases are handled and policies surrounding ratings. Below is a list of things that should be thought of before embarking on an adoption…

  1. IECC code year adopted?
  2. Adopt HERS or ERI rating?
  3. If HERS, what is the required score?
  4. If ERI, are test results required to be submitted?
  5. If ERI, what is done if test results do not comply?
  6. If ERI, what is done with mandatory items that do not comply?
  7. What is policy, how do you handle atmospherically detached ADUs?
  8. What is policy, how do you handle remodels?
  9. What is policy, how do you handle additions?
  10. What is policy, how do you handle off-grid houses?
  11. What is policy, if scores at final do not reach the goal?
  12. What is policy, in multi-family, is whole-building infiltration testing allowed? Or must units be tested for compartmentation?
  13. What is policy, withhold the TCO & CO until the confirmed rating certificate is issued?

HERS or ERI… To boil it down, the main difference here is that a HERS ratings don’t enforce the IECC. Whereas the ERI version has the Rater checking for mandatory IECC requirements and performing the required testing. AHJs that are relying on Raters as an extension of their own inspection staff, need to have an understanding of what Raters are looking for and what they are not. For instance, a Rater has to perform their own pipe insulation inspection, but they would have no reason to check the vapor retarder, snowmelt controls or pools and spas. Even if a Rater inspects and fails an IECC item, it doesn’t necessary mean that information will automatically be transmitted to the building department. It’s possible that the pipe insulation might fail the Rater’s inspection and pass the building department’s inspection, or visa-versa. HERS ratings scores are always more flattering than ERI scores. And HERS ratings come with a colorful certificate that gives a dollar amount of estimated savings. HERS ratings don’t have any pass/fail thresholds, so their flexibility can easily be used for existing and non-conforming homes. A HERS rating doesn’t require any construction inspections, although the score will benefit if the insulation is inspected, and it turns out to be better than default, which is “poor installation, grade III”. The HERS rating score (not ERI) will appear on the RESNET Registry, which is the database for the MLS (Multiple Listing Service). So if you go with ERI, it will not match the score listed on the MLS.

ADUs and other kinds of out buildings… Ratings don’t deal well with attached or unattached ADUs, guesthouses, party barns, etc. I recommend making a proactive statement in your adoption about how these kinds of things will be handled. Ignore ADUs entirely? Make ADUs stand on their own additional rating? Just an infiltration test for out buildings, no rating?

Remodels and additions… When a Rater inspects a project with existing assemblies and unstickered windows, they must assume the worst. The project will have a hard time making a good score with existing assemblies holding them back. Raters cannot rate just part of a house and ignore part. I recommend additions would be allowed to submit prescriptively, or are required to meet a less stringent score than new construction.

Compartmentalization…  I recommend making a proactive statement in your adoption about infiltration testing in multi-family buildings. Whole-building testing of multi-family buildings has been permitted in the past. Whole-building testing does not test the party wall, corridor wall and floor/ceiling assemblies. If individual unit testing is expected, then make that very clear up front. Typically party assemblies are not designed to create an airtight barrier between units. The unit-to-unit air leakage will make every unit perform poorly on the infiltration tests.

TCO before Confirmed rating…  It would be good to have a policy on whether or not projects can get a TCO before the Confirmed rating is issued. The pro is flexibility. For example, I have had projects lately that had major delays getting their solar installed. I am not able to final a job until the PV is on the roof and functioning. But a house can obviously be occupied safely without solar. Cons are that if people get to move in before I finish my inspection and testing, I often have access problems and new liabilities as a jobsite converts into someone’s home.

Plan for what happens when a project does not meet it’s score requirement… An ERI score is a moving target, it will fluctuate throughout a construction project. Details and specs become available, changes and substitutions are made, inspection and test results become available, etc. I always try to build in a small point buffer to offset any score creep, but invariably some projects will land above their target. Some jurisdictions will say that the project needs to do what is necessary to gain the missing points. Sometimes that works. I have been able to ask builders to upgrade a hot water recirculation pump at final to make up a couple of points. But pretty quickly we run out of options for making points that don’t involve taking the house apart in some way, significant occupation delays, etc. This puts a lot of pressure on the Rater as this starts to get into real money fast. And a Rater does not have the authority or protections of an agent of a governmental jurisdiction. Raters aren’t enforcement officers. There needs to be a way out of this situation. Some jurisdictions use a fee-in-lieu of points model. I suppose that is a reasonable way to go, probably with some limitations.

Thirteen facts about Raters and ratings every jurisdiction should know…

  1. Ratings are great for comparing the performance of simple, common, no-frills houses; production homes. The further from “average” the house is, the less reliable the rating is. I would not recommend using ratings alone to cap the energy consumption of custom luxury homes. Even if the software manages to compensate for the volume and glazing ration differences, once you start putting what are essentially commercial mechanical systems in a house, all bets are off.
  2. Rating software is much more sophisticated than something like REScheck, but not sophisticated enough to really handle a complex mechanical system with complex controls and operation. Especially dual-fuel houses.
  3. Rating software is not like mechanical system design software or Manual J & S software, like Wrightsoft or Elite. Rating software does not how to make “zones” comfortable, so I find it underestimates cooling loads in heavily glazed rooms.
  4. Rating software simultaneously checks the energy model for compliance with 36 different codes and programs including; 2006 IECC Prescriptive to 2021 IECC ERI, ENERGY STAR, LEED, 45L Tax Credit, etc.
  5. Ratings affect the construction schedule. As a job starts to wind down, there is often much pressure on a Rater to final inspect, test-out and produce a confirmed rating. Ratings cannot be finaled until the house is completely finished; solar installed, door hardware and thresholds installed, ventilators running, appliances etc. It takes at least two business days to get a final certificate from RESNET after a Rater makes the final inspection, builders often neglect to build this time into their schedule.
  6. Ratings are not black and white. Different software and different Raters may get slightly different results. The more complex the house, the more ratings will vary.
  7. Ratings don’t include all of the energy used in a project. Be cognizant of what is included in a rating and what is not. If you are trying to create a “total energy budget” for a house, know that ratings look only for specific items. People tend to ignore the little asterisks next to the HERS index utility bill estimate that says “*relative to an average U. S. home”. A model Renewables Energy Offset Program would need to catch, not just snow melted driveways and outdoor pools, but also everything about the house that is above “average” in order to have a comprehensive accounting of projected energy usage. And that “average” house is looking at a national scope, I find that almost all of the single-family houses I rate in Colorado are above average in the amount of energy that gets used beyond the scope of a rating. For instance rating do not capture… Anything outside the thermal boundary of the living spaces of the house, like; heated garages, ADUs, out buildings, pools, pool houses, fountains, patio kitchens, patio heating, snowmelt, hot tubs, etc. Items inside the house that a rating will not capture; make-up air for a large kitchen hood or draft inducer for a fireplace, steam showers, humidifiers, oxygen concentrators, elevators, radon fans, multiple redundant appliances, redundant heating systems, whirlpool tubs, pools, supplemental ventilation or dehumidification for pools, etc. We know from study by a local engineering firm (Resource Engineering Group, Crested Butte) that these items, that differentiate an average house from a custom luxury house, are the very things that make these houses exponentially more energy consumptive. Ignoring the burden of the luxury items is really a form of discrimination against anyone trying to build an average house.
  8. Ratings are very harsh on uninspected existing assemblies and unstickered windows. If a project covers insulation before I get to inspect it, I am required to assume the worst, and grade the insulation at the worst possible installation level; poor installation. This can add several points to the final score, even though the insulation may have been great. It would help Raters immensely if jurisdictions would stamp the drawings with something like, “Confirmed rating required for CO. Contact the Rater of Record at start of construction, before insulation is installed, after insulation is installed and at substantial completion.”
  9. Ratings don’t necessarily push projects to electrification. Ratings are based on dollars, not carbon. Ratings don’t know how clean or dirty the local electrical grid is. Science tells us that we should discourage the use of fossils fuels in new construction and embrace electrical technologies. If you want to incentivize electrification, then something more than a standard rating is required.
  10. Ratings are typically full of assumptions and the Projected level. Raters usually get Design Development drawings without PV design, appliance schedule, glazing specs, etc. The rating will gradually get more accurate as the project develops.
  11. Home Energy Raters are all certified by RESNET (Residential Energy Services Network) at least until another certification group emerges. Once certified, they can perform HERS, ERI ratings and issue IECC compliance documents. With a little more training and testing, they can issue ENERGY STAR documents. With a little more training and testing, they can become a Green Rater and issue LEED documents.
  12. Rater certification and maintenance is not easy. Raters have to take classes in Building Science and how to use the software. Then pass the tests. Then you have to intern on a number of probationary ratings, all before you start work. It takes a load of expensive equipment to actually perform ratings- usually have about $25,000 worth of equipment in my car. I have to pay dues to a company to provide QA (Quality Assurance) which means they review my work answer questions and process the record keeping. Every year I pay for that company to send a representative to one of my jobs to do a live rating review on the spot. Every three years I have to complete 18 hours of continuing education. Plus annual equipment calibration, insurance, vehicle and computer overhead.
  13. Raters have no power of enforcement on their own, other than the fear of a non-compliant score. No power to compel document changes, no power to reject work, no power to withhold a CO. If energy conservation measures are to be enforced on a project, then a Rater needs to be supported by the AHJ.

 

Below is my model code adoption language. Please use it, customize it and evolve it…

HERS model adoption language

  1. The AHJ will stamp the rating type, goal and any other special requirements on the cover sheet of the record documents kept on site.
  2. New construction projects, gut remodels and atmospherically detached Accessory Dwelling Units shall achieve a HERS score of 50 (Climate zone 7).
  3. Addition projects shall have a Home Assessment made of the existing structure and recommendations undertaken. New work to follow Prescriptive requirements. Final infiltration test not required.
  4. Multi-family units shall undergo compartmentation testing, whole-building tests will not be accepted.
  5. Off-grid houses shall follow the Prescriptive path.
  6. CO shall not be issued until confirmed rating is issued. A TCO may be issued for house that have completed testing but the confirmed rating is delayed for extenuating circumstances.
  7. If a site is deemed unsuitable for PV; projects may calculate how much solar is required and install that amount off-site. Or PV may be purchased at a community solar farm. Or the PV may be donated to another building in the community.
  8. Projects with non-compliant HERS scores shall; calculate how much additional PV it would take to make the score complaint and donate $7.00 per watt to a local community solar cooperative.

 

2021 IECC ERI model adoption language

  1. The AHJ will stamp the rating type, goal and any other special requirements on the cover sheet of the record documents kept on site.
  2. New construction projects and gut remodels shall achieve a 2021 ERI score of 60 without PV and a 2021 ERI score of 53 with PV (Climate zone 7).
  3. Atmospherically detached Accessory Dwelling Units shall achieve a 2021 ERI score of 53 (Zone 7).
  4. Addition projects shall have a Home Assessment made of the existing structure and recommendations undertaken. New work to follow Prescriptive requirements. Final infiltration test not required.
  5. All ERI requirements of 2021 IECC Table 406.2 shall be met. The AHJ shall be responsible for all inspections in enforcement of the IECC.
  6. Infiltration, ventilator efficacy and Total Duct Leakage test result reports shall be submitted.
  7. Ventilator flow test result reports shall be submitted. Non-compliant ventilation flows shall be rectified and re-tested. In the event of the test not being able to be executed for technical reasons, ventilation flows may rely on manufacturer’s data plate specifications.
  8. Multi-family units shall undergo compartmentation infiltration testing, whole-building tests will not be accepted.
  9. Off-grid houses shall follow the Prescriptive path.
  10. CO shall not be issued until confirmed rating is issued. A TCO may be issued for house that have completed testing but the confirmed rating is delayed for extenuating circumstances.
  11. If a site is deemed unsuitable for PV; projects may calculate how much solar is required and install that amount off-site. Or PV may be purchased at a community solar farm. Or the PV may be donated to another building in the community.
  12. Projects with non-compliant ERI scores shall calculate how much additional PV it would take to make the score complaint and donate $7.00 per watt to a local community solar cooperative.

Please note that I work in the mountains, custom luxury home market- climate zones 6 and 7. This could all change quite a bit in another part of the country. I don’t know a thing about termites, exterior vapor retarders, radiant barrier, etc.…

Thank you,

Mark McLain

Architect

ICC/HERS Compliance Specialist

ICC Residential Energy Inspector/Plans Examiner

RESNET Certified Home Energy Rater

BPI Building Analyst Professional

BPI Multi-family Building Analyst Professional

 

Link to Colorado Energy Conservation Code Hub for; Aspen, Basalt, Carbondale, Eagle County, Pitkin County, Town of Snowmass Village and the Town of Mountain Village

Recommendations from a Rater for Adopters of the 2018 or 2021 IECC Energy Rating Path

Ratings are a great tool for evaluating the projected performance of unbuilt houses. Many good points; they get projects into a simple energy model that can be used to Value Engineer the most cost-effective version of the proposed house, they put another set of eyes on the work- looking specifically for energy conservation issues, etc. But they do have their shortcomings. Here are a few places I can think of where other jurisdictions have had problems with the application of their adoptions recently…

HERS (Home Energy Rating Score) or ERI (Energy Rating Index)…

Be specific about the adoption language regarding the yardstick you want to measure by. In 2015 HERS and ERI scores were the same. In 2018 HERS and ERI adopted different base standards, and now the scores do not align. ERI scores are harder to reach than HERS scores in 2018 and 2021. The other core difference between the two; ERI reports come with a list of “mandatory” items that have to be done per the IECC (International Energy Conservation Code) ; like pipe insulation. If I fail someone on a poor pipe insulation job, it will show up as a big red problem on the ERI report. HERS doesn’t have any “mandatory” items, no pass/fail. You can get a HERS score no matter what. I can give you a HERS score on an existing house, even though I can’t inspect the pipes.

Accessory Dwelling Units and other kinds of out buildings…

Ratings don’t deal well with attached or unattached ADUs, guesthouses, party barns, etc. I recommend making a proactive statement in your adoption about how these kinds of things will be handled. Ignore ADUs entirely? Make ADUs stand on their own additional rating? Just an infiltration test for out buildings, no rating?

Remodels and additions…

When a rater inspects a project with existing assemblies and unstickered windows, they must assume the worst. The project will have a hard time making a good score with existing assemblies holding them back. Raters cannot rate just part of a house and ignore part. I recommend additions would be allowed to submit prescriptively, or are required to meet a less stringent score than new construction.

Compartmentalization…

I recommend making a proactive statement in your adoption about infiltration testing in multi-family buildings. Whole-building testing of multi-family buildings has been permitted in the past. Whole-building testing does not test the party wall, corridor wall and floor/ceiling assemblies. If individual unit testing is expected, then make that very clear up front. Typically party assemblies are not designed to create an airtight barrier between units. The unit-to-unit air leakage will make every unit perform poorly on the individual infiltration tests.

Issue TCO (Temporary Certificate of Occupancy) before Confirmed Rating…

It would be good to have a policy on whether or not projects can get a TCO before the Confirmed rating is issued. The pro is flexibility. For example, I have had projects lately that had major delays getting their solar installed. I am not able to finish a job until the PV is on the roof and functioning. But a house can obviously be occupied safely without solar. Cons are that if people get to move in before I finish my inspection and testing, I often have access problems and new liabilities as a jobsite converts into someone’s home.

Missed inspections…

If a project covers insulation before I get to inspect it, I am required to assume the worst, and grade the insulation at the worst possible installation level. This can add several points to the final score, even though the insulation may have been great. It would help raters immensely if jurisdictions would stamp the drawings with something like, “Confirmed rating required for CO. Contact the Rater of record at start of construction, before insulation is installed, after insulation is installed and at substantial completion.”

Have a plan for what happens when a project does not meet it’s score requirement…

A rating score is a moving target, it will fluctuate throughout a construction project. Details and specs become available, changes and substitutions are made, inspection and test results become available, etc. I always try to build in a small point buffer to offset any score creep, but invariably some projects will land above their target. Some jurisdictions will say that the project needs to do what is necessary to gain the missing points. Sometimes that works. I have been able to ask builders to upgrade a hot water recirculation pump at final to make up a couple of points. But pretty quickly we run out of options for making points that don’t involve taking the house apart in some way, significant occupation delays, etc. This puts a lot of pressure on the rater as this starts to get into real money fast. And a rater does not have the authority or protections of an agent of a governmental jurisdiction. Raters aren’t enforcement officers. There needs to be a way out of this situation. Some jurisdictions use a fee-in-lieu of points model. I suppose that is a reasonable way to go, probably with some limitations.

Have a plan for what happens when a project does not meet test requirements…

Several tests may be run in the course of a rating; infiltration, duct leakage, ventilation flows, ventilator watt draw, etc. An ERI report will show tests that did not comply with the IECC, but with a HERS rating the test reports may not be automatically supplied with the confirmed rating certificate. The test results will be incorporated into the model, but there is no pass-fail threshold related to the IECC. Recommend deciding ahead of time if test reports will be collected and reviewed. Is there going to be some consequence for failing IECC tests? Are they expected to be remediated and re-tested?

Be cognizant of what is included in a rating and what is not…

If you are trying to create a “total energy budget” for a house, know that ratings look only for specific items. People tend to ignore the little asterisks next to the HERS index that says “*relative to an average U. S. home”. A model Renewables Energy Offset Program would need to catch, not just snow melted driveways and outdoor pools, but also everything about the house that is above “average” in order to have a comprehensive accounting of projected energy usage. And that “average” house is looking at a national scope, I find that almost all of the single-family houses I rate in Colorado are above average in the amount of energy that gets used beyond the scope of a rating. For instance rating do not capture… Anything outside the thermal boundary of the living spaces of the house, like; heated garages, ADUs, out buildings, pools, pool houses, fountains, patio kitchens, patio heating, snowmelt, hot tubs, etc. Items inside the house that a rating will not capture; make-up air for a large kitchen hood or draft inducer for a fireplace, steam showers, humidifiers, oxygen concentrators, elevators, radon fans, multiple redundant appliances, redundant heating systems, whirlpool tubs, pools, supplemental ventilation or dehumidification for pools, etc. We know from study by a local engineering firm (Resource Engineering Group, Crested Butte) that these items, that differentiate an average house from a custom luxury house, are the very things that make these houses exponentially more energy consumptive. Ignoring the burden of the luxury items is really a form of discrimination against anyone trying to build an average house.

Ratings don’t understand batteries, whole-house generators or houses that are not connected to the electrical grid…

It doesn’t come up much, but just beware that houses that don’t fit into the rating box very well, may require/deserve an alternative approach to show compliance.

Electrification…

Ratings are based on dollars, not carbon. Ratings don’t know how clean or dirty the local electrical grid is. Science tells us that we should discourage the use of fossils fuels in new construction and embrace electrical technologies. Ratings don’t necessarily push new construction towards electric as a fuel. If you want to incentivize electrification, then something more than a standard rating is required.

Thanks,

Mark McLain

Architect & Sustainability Consultant

 

Link to Colorado Energy Conservation Code Hub for; Aspen, Basalt, Carbondale, Eagle County, Pitkin County, Town of Snowmass Village and the Town of Mountain Village

San Miguel County Energy Code

Starting sometime in 2023…

2018 ERI 61-PV or 56+PV

A maximum design score of 61 without including offsetting means through onsite renewable energy.

OR
A maximum design score of 56 that includes offsetting means through onsite renewable energy.

https://www.sanmiguelcountyco.gov/157/Building

 

CHAPTER 11 ENERGY EFFICIENCY
N1101.13 (R401.2) Compliance. Amend Section to read: Projects shall comply with one of the following:
1. Sections N1101.14 through N1104.
2. Section N1105 and the provisions of Sections N1101.14 through N1104 indicated as “Mandatory.”
3. The energy rating index (ERI) approach in Section N1106. Projects shall provide a preliminary design in
which one of the two are modeled:
• A maximum design score of 61 without including offsetting means through onsite renewable energy.
• A maximum design score of 56 that includes offsetting means through onsite renewable energy.
N1101.13.1 (R401.2.1) Required ERI approach. All of the following are required to comply with N1101.13, item
3. Floor area calculations for purposes of this section shall be defined as the floor area within the
inside perimeter of the exterior walls of the building under consideration, exclusive of vent shafts
and courts, without deduction for corridors, stairways, ramps, closets, the thickness of interior walls,
columns or other features, attached garages, and crawlspaces 6 feet 4 inches in height or greater,
measured from grade/floor to bottom of joist/floor assembly above:
1. New single‐family dwellings whose floor area is 3,600 square feet or greater.
2. New two‐family dwellings whose aggregate floor area is 4,000 square feet or greater.
3. New townhomes.
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N1101.15 (R401.4) Renewable Energy Mitigation Program (Mandatory). Add Section N1101.15 (R401.4) to read: San
Miguel County’s Renewable Energy Mitigation Program (REMP) is designed to help offset the effects of outdoor
energy consumption that contribute to the effects of greenhouse gas emissions. The provisions of REMP shall be
applied as follows:
N1101.15.1 (R401.4.1) Scope. Energy used to power hydronic snowmelt systems, factory‐built and site‐built
spas located on the exterior, pools located on the exterior, and heated garages for all new residences,
accessory structures, commercial facilities, alterations, and additions shall be mitigated through REMP
and shall comply with N1101.15.1 through.
N1101.15.1.1 (R401.4.1.1) Snowmelt. All snowmelt anywhere on the property shall be offset by REMP.
All snow melt systems shall be equipped with both moisture and temperature sensors to control
operation per the IECC and IRC. Hydronic snow melt systems shall have a minimum of R‐15
insulation on the non‐snow melt side.
Exceptions:
1. Single-family development: 200 square feet of exempt hydronic snow melt shall be
allowed without mitigation located only on the main drive and/or code required exit
walkways, decks, stairs and landings.
2. Multi-family, mixed use, accessory use, and commercial development: 100 square feet
plus 25 square feet per dwelling unit of exempt hydronic snow melt shall be allowed
without mitigation located only on the main drive(s) decks, amenity areas and/or code
required exit walkways, stairs and landings.
3. Two-family residences and townhomes: 50 square foot of exempt per dwelling unit
hydronic snowmelt shall be allowed without mitigation located only on the main drive
and/or code required exit walkways, decks stairs and landings.
Definition of Exempt Snow-Melt Area: Tubing installed to melt snow on a surface
intended to remove snow from the walkable or drivable area shall be measured by the
size of the entire potentially snow‐melted area. For example, if a 10 ft. x 20 ft. deck only
has perimeter snow melt tubing, the entire area shall be counted toward the snow melt
exemption.
N1101.15.1.2 (R401.4.1.2) Spas. All spas located on the exterior of a building shall be offset by REMP.
Exterior heated spas must comply with the currently adopted Energy Codes.
N1101.15.1.3 (R401.4.1.3) Exterior Pools. All pools located on the exterior of a building shall be offset
by REMP. Exterior heated swimming pools must comply with the currently adopted Energy
Codes.
N1101.15.1.4 (R401.4.1.4) Heated Garages. All heated garages shall be offset by REMP. Heated garages
must comply with the currently adopted Energy Codes. All heated exterior garage portal doors
shall have a minimum R‐value of R‐18. The blower door test required as per IRC Section
N1102.4.1.2 and IECC Section R402.4.1.2 shall apply only to the homes habitable space and the
air sealing for the garage shall be visually inspected.
N1101.15.2 (R401.4.2) Energy Use Calculation. The total exterior energy use that must be mitigated with
renewable energy or payment made as a payment in‐lieu as allowed in these regulations will be
calculated by the owner/agent and verified by the County Building Official using the San Miguel County
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REMP Worksheet (“Worksheet”). The Worksheet is attached at end of IRC amendments as Appendix Z
and a fillable version can also be found at www.sanmiguelcountyco.gov/building. The Worksheet
calculations were developed using the standard amount of energy used by the exterior systems and
adjusted for local climatic conditions as calculated by Resource Engineering Group (2013). The
Worksheet will be updated regularly according to market fluctuations and may be amended by
resolution.
N1101.15.2.1 (R401.4.2.1) Renewable Energy Credit Calculation. Mitigation of outdoor energy use may
be achieved by onsite renewable energy systems approved by the Building Official. The payment
in lieu shall be calculated using the Worksheet.
N1101.15.2.1.1 (R401.4.2.1.1) Alternative technology. As new technology or other offsite
renewable energy projects develop, they may also be considered as approved mitigation
systems by the Building Official.
N1101.15.2.1.2 (R401.4.2.1.2) Combination of measures. If the amount of renewable energy
capable of being produced onsite by one system is not sufficient to mitigate exterior
energy use as outlined, a combination of renewable energy methods may be used as
approved by the Building Official.
N1101.15.2.2 (R401.4.2.2) Payment in-lieu. If preferred by the property owner, the owner may make a
one‐time payment to San Miguel County in‐lieu of providing onsite mitigation by a County
approved renewable energy system. San Miguel County may also accept partial payment in lieu
from the affected property owner when only partial onsite mitigation of exterior energy use
occurs. The owner shall make payment prior to receiving the building permit. The payment in‐
lieu shall be calculated using the Worksheet.
N1101.15.2.2.1 (R401.4.2.2.1) Appropriation of Funds. All REMP payments in lieu received by
the County shall be deposited into a separate fund called the “San Miguel County Energy
Fund” (Fund). All monies deposited into such Fund shall be used solely within San
Miguel County for the purposes of:
1. funding capital expenses associated with purchase, installation, and/or construction
of renewable energy or energy conservation facilities;
2. and/or funding projects that help to mitigate greenhouse gas emissions.
The Board of County Commissioners shall approve expenditures from the Fund after
receiving recommendations from the County staff and the County Manager.
N1101.15.3 (R401.4.3) Approved Renewable Energy Systems. All renewable energy systems proposed as a
means of exterior energy use mitigation must be approved in advance by the Building Official. An
engineering analysis may be required for calculating the renewable energy mitigation credit produced
by an onsite or offsite system. Review of the system by a County engineering consultant, if needed, will
be at the expense of the owner.
N1101.15.3.1 (R401.4.3.1) Perpetuity of onsite mitigation. Onsite renewable energy systems provided
to mitigate exterior energy are required to be maintained and operated for the lifetime of the
structure, through a written agreement with the property owner and a covenant on the
property.
N1101.15.3.2 (R401.4.3.2) Off-site Mitigation. Off‐site renewable mitigation shall only be approved by
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the Building Official if, through a written agreement:
1. the system is legally tied to the property using exterior energy use with the inability to
transfer to another property;
2. the County, at any time, can verify through audits that the offsite renewable energy
system continues to provide renewable energy as provided for herein, with no
restrictions on the County’s ability to accessrenewable energy utility information.
N1102.1 (R402.1) General (Prescriptive). Amend “Exceptions” Item 2 as follows:
Exceptions:
2. Log homes designed in accordance with ICC-400 with glazing to floor area ratio of 18% or less and
passing air leakage test demonstrating 3ACH 50 or less.
N1103.9 (R403.9) Snow melt system controls (Mandatory). Amend Section to read: Snow‐ and ice‐melting systems,
supplied through energy service to the building, shall include automatic controls capable of shutting off the
system when precipitation is not falling, and an automatic control that will allow shutoff when the outdoor
temperature is greater than 40°F (4.8°C).
N1103.13 (R403.13) Outdoor heating equipment (Mandatory). Add Section to read: All outdoor space heating
equipment supplied through energy service to the building such as, but not limited to, fire pits, heaters,
fireplaces, etc., shall be equipped with 60‐minute automatic shutoff timers.
N1106.3 (R406.3) Energy rating index. Amend Section to read: The Energy Rating Index (ERI) shall be
determined in accordance with RESNET/ICC 301. [STRIKE ERI reference design ventilation rate Equation
11-1].
N1106.4 (R406.4) ERI-based compliance. Compliance based on an ERI analysis requires that the rated design be
shown to have an ERI less than or equal to the appropriate value indicated in Table N1106.4 when
compared to the ERI reference design.
TABLE N1106.4 (R406.4) MAXIMUM ENERGY RATING INDEX. Amend Table as follows:
TABLE N1106.4 (R406.4) MAXIMUM ENERGY RATING INDEX
CLIMATE ZONE ENERGY RATING INDEXa
6 61 without onsite renewable energy in model;
56 with onsite renewable energy in model
[STRIKE footnote a]
N1107.2 (R501.2) Existing buildings. Except as specified in this chapter or by other locally enforced law, ordinance,
resolution, or code, this code shall not be used to require the removal, alteration or abandonment of, nor prevent
the continued use and maintenance of, an existing building or building system lawfully in existence at the time of
adoption of this code.

 

Link to Colorado Energy Conservation Code Hub for; Aspen, Basalt, Carbondale, Eagle County, Pitkin County, Town of Snowmass Village and the Town of Mountain Village

Getting to Zero

Confluence Architecture was instrumental in turning an old 1970 energy hog home into a an efficient, low energy use residence.   The project qualified for $12,000 in  grants from CORE and $7,092 in rebates from Holy Cross Energy.      The home is fully electric and uses air-source heat pumps for heating and cooling.  It is projected to be net-zero. Confluence was responsible for planning, architecture and energy modeling on this home.

Before

           

 

After