UPDATE: Michigan has adopted the 2015 Michigan Residential Code which contains the new provisions for the energy portion. This was implemented on February 8, 2016. Information in this blog post may be outdated. Visit this PAGE for updated information on the code change.
In May of this year, the battle for the new energy code has finally come to an end! The Dow Chemical Company and HBA of Michigan agreed on proposed changes to the new residential energy code in Michigan. The code review committee approved them on July 10th. This is great news for the entire industry and most importantly homeowners. It will provide increases in energy efficiency in new homes as well as keeping the costs at an affordable level for builders and home buyers.
This is long over due unfortunately. Michigan is behind many states throughout the US from an energy efficiency standpoint. We are currently on the 2009 version of the code. This change will put us on a variation of the 2012 code. The 2015 code has been published, which gives you an indication of how far behind the state is compared to current available codes. Either way, we are glad this is finally taking some ground. This new code is expected to go into effect around May of 2016.
- Wood Frame Wall R-Values – Prescriptive path will remain at the 2009 levels for Climate Zone 5 & 6 (20 or 13+5). Climate Zone 7 will reduce from the 2009 level of R21 to 20 or 13+5.
- Basement Wall R-Values – Prescriptive path table will remain the same. 10/13 for Zone 5 and 15/19 for Zones 6 & 7
- Crawl Space Wall R-Values – Prescriptive path will increase from 2009 levels of 10/13 for Climate Zones 5, 6 and 7 to the 2012 prescriptive path of 15/19.
- Ceiling R-Value – Prescriptive path for Climate Zone 5 will remain the same at R-38. No changes to Zones 6 & 7 which are at R-49.
- Air Changes Per Hour– Mandatory air changes per hour will decrease from 7 ACH50 to 4 ACH50 with a trade off in the performance path for reducing the ACH50 below 4.
- Blower Door Testing – Code officials will no longer be able to hand pick an approved 3rd party to conduct blower door testing. The will be able to require testing to be conducted by a certified independent 3rd party but will not be able to choose which party. Certification programs for blower door testers shall be approved by the State Construction Code Commission. Building officials will no longer be able to require an approved 3rd party to inspect all components of the building thermal envelope.
- Post Construction Duct Leakage Testing – Duct Leakage Testing may be done to either the outside of the conditioned space or to total leakage. The allowable total leakage rate is less than or equivalent to 4 CFM per 100 square feet of conditioned floor area. There will be a trade off in the performance path for reducing the leakage rate below 4 CFM per 100 sq feet.
- Circulating Hot Water Piping Insulation R-Value – Will increase from the 2009 requirement from R-2 to R-3. Piping from the water heater to the kitchen outlets will not need to be insulated. These requirements only apply to: Piping larger than 3/4 inch, piping serving more than one dwelling unit, piping located outside conditioned space, piping from water heater to distribution manifold, piping located under a slab floor, buried piping and supply & return piping in recirculation systems other than demand recirculation systems.
- Re-roofing – where the roof is part of the thermal envelope, and where neither the roof sheathing nor the roof insulation is exposed as well as re-roofing is not part of the thermal envelope will not need to comply with Chapter 11 provided the energy use of the building is not increased.
- Trade Offs – No trade offs in the performance path for either the use of high-efficiency mechanical equipment or any reduction in fenestration percentage below 15%.
- Above Code Programs – Will no longer be approved by the individual building official. The State Construction Code Commission will evaluate and approve all above code programs. Compliance with an approved above code program will be deemed to meet the requirements of Chapter 11.
That is it in a nutshell. It is to my understanding that the energy code will now be a part of the general building code, instead of a separate reference. Many builders that we work with will be just fine when these changes come, but there are some that will need to make changes. Builders already doing HERS Index Ratings on their projects will be more prepared for this change than builders who are not.
It looks like blower door testing will be mandatory. Getting the results to under 4 ACH50 will be no problem for the majority of builders. Most of our clients are landing between 2 & 3 ACH50.
Duct leakage will be a bigger issue. HVAC contractors are going to need to start tightening up the duct work better than what we are seeing. 4% total leakage is going to be hard to hit.
Call us at 616-419-8558 for more information on these proposed changes. We will keep our website up to date as best we can as this comes closer.
Reference : Michigan Builder Magazine, HBA of Michigan