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. JHAs 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 JHA 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 JHA 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 JHA 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

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 not include onsite renewable energy
systems in their preliminary rating design and score.
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 over 3,600 square feet of floor area or greater.
2. New two‐family dwellings whose aggregate floor area is 4,000 or greater.
3. New townhomes.
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
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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
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
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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 inlieu
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
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 access renewable energy utility information.
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.
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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. Maximum ERI for climate zone 6 until May 30th, 2022 is 70.

 

 

AMENDMENTS TO THE 2018 INTERNATIONAL ENERGY CONSERVATION CODE
C101.1 AND R101.1 Title. Amend Sections to read: These regulations shall be known as the Energy Conservation Code of
San Miguel County, hereinafter referred to as “this code.”
SECTIONS C109 and R109 Means of Appeal. Delete Sections in its entirety (C.R.S §§ 30‐28‐206 and 30‐28‐207 apply).
R401.2 Compliance. Amend Section to read: Projects shall comply with one of the following:
1. Sections R401 through R404.
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2. Section R405 and the provisions of Sections R401 through R404 indicated as “Mandatory.”
3. The energy rating index (ERI) approach in Section R406. Projects shall not include onsite renewable energy
systems in their preliminary rating design and score.
R401.2.1 Required ERI approach. All of the following are required to comply with R401.2, item 3. Floor area
calculations for purposes of this section, the floor area, measured in square feet, shall include unfinished
basements, 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 over 3,600 square feet of floor area or greater.
2. New two‐family dwellings whose aggregate floor area is 4,000 or greater.
3. New townhomes.
R401.4 Renewable Energy Mitigation Program (Mandatory). Add Section 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:
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 R401.4.1.1 through R401.4.1.4.
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.
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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.
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.
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.
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 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.
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.
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.
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.
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.
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
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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.
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.
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.
R401.4.3.2 Off‐site Mitigation. Off‐site renewable mitigation shall only be approved by 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 access renewable energy utility information.
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).
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.
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 R406.4 when compared to the ERI reference
design. Maximum ERI for climate zone 6 until May 30

 

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

      

Snowmass Village Energy Code Requirements

Town of Snowmass Village Community Development website here…

2015 International Energy Conservation Code (IECC) and REOP adoption…

Ordinance No. 2 2011  adoption…

Town of Snowmass Village CFA Maximum
Tier I 1000-3000 HERS 75
Tier II 3001-5000 HERS 70
Tier III 5001-10000 HERS 65
Tier IV 10000+ HERS 60

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

Town of Mountain Village

As of August 20, 2020…

2018 International Energy Conservation Code

Special provisions for exterior energy use.

Permit fee discounts available for nonexistent or offset exterior energy uses.

Link to Town website and adoption language…

CFA TOMV yes snowmelt no snowmelt
< 3600 Tier I prescriptive prescriptive
3601-7000 Tier II 2018 HERS 60 2018 HERS 60
7001-13000 Tier III 2018 HERS 55 2018 HERS 60
13001+ Tier IV 2018 HERS 50 2018 HERS 60

 

Hi Allison,

I wanted to follow up after our conversation this morning addressing the issue of mechanical rooms and unconditioned space in new construction in the Town of Mountain Village.

As a policy we are allowing for mechanical rooms, and unconditioned garages to be exempted from habitable HERS calculations with the following criteria;

  • No heating of any type will be permitted in these locations
  • Exterior envelope insulation requirements shall be met for ALL walls, ceilings and floors (per the HERS design), with a designed thermal break at floors, including concrete (Check with your engineer as this may cause problems with structural slabs).
  • Doors to these rooms shall be fully gasketed
  • At least one, or a minimum of 25% of the walls shall be directly adjacent to the exterior of the structure.

As you are aware, our CDC and the 2018 IECC do not specifically provide for the installation of PV systems to offset HERS ratings in a residential application. The allowance above will hopefully provide for an easier time of meeting the HERS requirements of the Town, and meets prescriptive requirements. In the future, if one of your raters can provide additional information to review that will support the PV to HERS tradeoff, we are available to review.

Thank you and please contact me with any questions

 

Lars Forsythe

Building Inspector

Building Department

Town of Mountain Village

455 Mountain Village Blvd, Suite A

Mountain Village, CO 81435

O :: 970.369.8246

C :: 970.729.3439

 

Performance HERS changes
Currently the Mountain Village Building Regulations has adopted the 2018 energy code. Per (section 17.7.12.7.i.D) renewable energy sources can be used to lower the HERS score if the Smart Build Program is utilized. Buildings designed with a HERS rating below 50 is the starting threshold to allow the renewable offset. It has come to my attention that RESNET/ICC 301 allows for renewable energy sources to be used to lower the HERS score. In keeping with our commitment to support renewable energy the Mountain Village Building Department has reviewed this document and will allow renewable energy to aid in lowering the HERS score. Effective immediately the Mountain Village Building Department will allow all new residential projects to utilize renewable energy sources to lower the HERS score providing:
(1) All 2018 IECC Residential Mandatory requirements in chapter 4 are utilized.
(2) Depending on the type of construction the minimum requirements of 2018 IECC Tables 402.1.2, 402.1.4 and 402.2.6 are followed prior to the addition of the renewable energy source to assist in the HERS score.
(3) Building Regulations section (17.7.12.D. V.I. A), the onsite renewable energy system will be required to be maintained and operational for the lifetime of the property, through a written agreement with the property owner and a covenant on the property.
Inspection Changes as follows:
The Mountain Village Building Department will require the Performance Rater to perform all the insulation inspections. The Performance Rater will be required to sign off on the pre-drywall inspection prior to drywall being installed as well as any partial inspections. An acceptance email must be sent to the building department for all inspections as well as the final acceptance certificate prior to CO being issued. The Building Department will provide a red line stamp on the reviewed plans stating (3rd party insulation inspection required) to help the contractor be aware of this requirement. The following emails may be utilized for the acceptance reports: larsforsythe@mtnvillage.org and dharrington@mtnvillage.org.
Sincerely Drew Harrington
Chief Building Official
970- 708-7537
970- 369-8251

 

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

New Home in Aspen Glen Completed

We are excited to showcase a new home we designed in Aspen Glen.  It is a 2500 sf, 3 bedroom home for a young family. The form of the home has 2 axis to respond to a challenging parallelogram lot. The home includes  indoor/outdoor features including an in and out bar window between the kitchen and rear patio. The master bedroom has a wrap around deck with views oriented towards t Mount Sopris.

     

 

A new home for Little Blue Preschool

Confluence Architecture along with local non-profit  Blue Lake Preschool  is honored to announce that after searching  for 5 years they were able to find a permanent location. Last September, Blue Lake Preschool  acquired the  property at 55 N 7th st, which happens to be the former residence of Mary Ferguson, a Carbondale icon. She was born at Spring Gulch in 1906, taught in one room schoolhouses, was a town council member, a volunteer and historian.  We find this connection to be a valuable  continuation of  Mary’s love of teaching.

Construction is now underway on the addition and remodel to to transform this 1950’s ranch home into an energy efficient  healthy and cozy preschool. Some of the energy efficiency  attributes include  addressing air circulation and filtration by utilizing a HRV system with Merv 13 filter, and upgrading  the insulation.  We seek to replace all the flooring with environmentally friendly natural linoleum and will use zero or low VOC paints.

Confluence Architecture has thrown its support behind this worthy project by contributing our professional services of  planning, property analysis, and Architectural services.  Blue Lake Preschool  is seeking funding to assist with construction.  This permanent home will allow Little Blue to increase the number of infant care spaces in Carbondale, a critically underserved demographic. We encourage all to donate to this worthy cause.  Donations can be made at Blue Lake’s website  https://bluelakepreschool.org/donate.

Town of Telluride Energy Conservation Code

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…

Link to adoption language, Article 9…

effective February 18, 2020

Mandatory ERI path

2018 ERI 61 (zone 6)

 

Adopted the 2018 version of the IECC

c) Residential Energy.

(1) Amend Section R401.2 “Compliance” to read:

All new buildings and any building having an addition of 1000 square feet or greater shall comply with Section R406. All other buildings shall comply with one of the following:

The remainder of the section remains unchanged.

(2) Add new Section R402.2.14 “Exterior walls” to read:

R402.2.14 Exterior Walls. Recess step lights are not permitted in exterior building walls except where the required R-value is met for the wall assembly.

(3) Add a sentence to Section R402.4.5 to read:

Recessed can lights are allowed in ceiling-roof assemblies only if the required R-value of insulation can be met between the top of the fixture and the roof decking material.

(4) Amend Table R402.4.1.1 by adding to the Insulation Installation Criteria for the Walls Component:

Wood or Engineered Headers-R-10 wherever possible.

Steel Header – R-10 with insulation provided on both the exterior and/or the interior sides of the steel if possible, to maintain a continuous thermal barrier.

(5) Amend Section R403.5.3 to read:

R403.5.3 Hot water pipe insulation (Mandatory). Insulation for hot water piping with a thermal resistance, R-value, of not less than R-3 shall be applied to the following:

Items 1 through 7 remain unchanged.

8. Hot water line piping shall not be placed in an exterior wall to the extent practical. When not practical as determined by the Building Official, hot water piping may be placed in an exterior wall provided the required insulation R-value of the wall is provided in between the piping and the exterior of the wall.

9. An insulating blanket shall be provided that covers entire water tank fastened with appropriate tape.

(6) Add a last sentence to Section R403.7 to read:

Systems shall be designed by a certified Mechanical Engineer for single family residential structures greater than 2,000 sq. ft. of gross floor area including the basement area.

(7) Amend Section R406.1 to add to the following as the last sentence:

ERI refers to the ERI Home Energy Rating System (HERS) score.

(d) Additional Requirements for Residential and Commercial Buildings.

(1) Cement. All cement used within the Town shall be mixed with western coal fly ash, except such a mix is not required for exterior slabs.
(2) Low Volatile Organic Compounds (“VOC”). The general contractor and the property owner shall sign the Homeowner VOC Awareness Checklist provided by the Town prior to the issuance of a certificate of occupancy for a project.
(3) Energy Star Ratings. Energy Star rated appliances, exhaust fans and light fixtures shall be installed.
(4) Exterior vegetation irrigation systems shall be installed with a moisture sensor and timer to control irrigation.

(5) Pools and Spas (Hot Tubs).

a. Exterior swimming pools are prohibited in Telluride unless otherwise approved by the Planning and Zoning Commission pursuant to the use permitted on review development review process contained in the Telluride Land Use Code.
b. Pools, custom-built hot tubs, or factory-built portable spas shall also meet the Energy Mitigation Program requirements in Section 15-9-40.
c. Pools, custom-built hot tubs, or factory-built portable spas shall be equipped with a vapor-retardant pool cover on or at the water surface. Pools/spas capable of being heated above 90 degrees F must have a pool cover with a minimum insulation value of R-16.
(6) Garage door for heated garages shall have a value of R-18.
(7) Electrical resistance heating in living space is prohibited except for (a) the replacement of an existing system that is not subject to meeting the requirements of the Energy Code as provided in Subsection (c) of this Section; or (b) for heating small spaces less than one hundred (100) square feet.
(8) Mechanical Systems. Roofs shall be designed to not need electric underlayment mat heating unless approved by the Building Official and shall require temperature and moisture sensors.
(9) Snow- and ice-melting systems shall include automatic controls configured to shut off the system when the pavement temperature is above fifty (50) degrees F (ten (10) degrees C) and precipitation is not falling, and an automatic or manual control that is configured to shut off when the outdoor temperature is above forty (40) degrees F (four (4) degrees C). Electric resistance snow/ice melt systems are prohibited except for the heat tracing of gutters and associated downspouts. Snow/ice melt systems (except roof or gutter heat tracing) shall also meet the Energy Mitigation Program requirements in Section 15-9-40.
(10) Construction Waste. All sites shall have at least two (2) lockable bear-proof polycarts for (a) food items and (b) recyclables.

(11) Renewable Energy.One hundred percent (100%) of the building’s electricity use must be provided for with renewable energy, either produced on site or purchased through a Green Power Production Program. Creative alternative options will be considered by the Building Department. (Ord. 1502 §1, 2020)

 

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