Ideas to consider for Residential Buildings attempting to meet the 2016 Energy Code, effective January 1, 2017
Design Review
"The best buildings result from an integrated design process: a continual, organized collaboration of a team of professionals that may include architects, designers, a variety of engineers, contractors, subcontractors, Energy Consultants, Building Inspectors, HERS Raters and many others. As 2020's Zero Net Energy goals approach, the need for early and regular collaboration between these professionals is essential."
As a result of this fact, CompuCalc is now offering "Design Stage" Energy Analysis. This will make it easier to integrate energy compliance requirements into the drawings and save costs of re-doing drafting & design. Call or ask today for a fee structure that includes a "Design Stage" Energy Analysis.
Energy Compliance is not just a form needed to obtain a building permit. Energy compliance is a process that begins at design stage and ends at the final building inspection. Elizabeth Smithwick of CompuCalc consults and guides through the entire building process as needed. CompuCalc's fee structure is built on this premise.
Mechanical Systems
- Request a Low Leakage Air Handler Unit from Heating & Air Conditioning Contractor.
- Request EER (not to be confused with SEER) ratings of 13 or higher for the air conditioning system from the Heating & Air Conditioning Contractor or Mechanical Designer.
- Consider preparing and HVAC System & Duct Design during the design phase. This will help define energy ratings for equipment; consider best design for duct systems supply and return air and duct length and determine if other energy credits would be available based on the proposed duct design. CompuCalc can help in this area. Joel Smithwick, HVAC contractor provides residential mechanical designs using ACCA Manual J (as required by the CA Building Energy Efficiency Standards — see below), Manual D and Manual S:
Section 150(h) Space-Conditioning Equipment.
- Building Cooling and Heating Loads. Building heating and cooling loads shall be determined using a method based on any one of the following:
- The ASHRAE Handbook, Equipment Volume, Applications Volume, and Fundamentals Volume; or
- The SMACNA Residential Comfort System Installation Standards Manual; or
- The ACCA Manual J.
- Building Cooling and Heating Loads. Building heating and cooling loads shall be determined using a method based on any one of the following:
- Install whole house fans: the requirement is for 1.5 cfm per square feet. Products can be located at the California Energy Commission's Title 20 Appliance Database, under Public Search choose "Apppliance Search".
- Water Heating: Specify gas-fired, tankless water heaters. Under the 2016 Energy Code a gas-fired, tankless water heater is the standard and the standard energy budget is set using this type of water heater. Therefore, any storage type water heater will be seen as below the budget and other energy measures will be needed to balance the energy budget. Electric water heating (tankless or storage) will continue to have a large negative effect on the energy budget, unless it is an electric heat pump water heater with an energy rating of 2.75 or better.
- Consider installing PV Solar. A system of 2.0 kwDC will have a positive effect.
Building Envelope
- Specify a Cool Roof Rated roofing product. Products can be located at the Cool Roof Rating Council website. Look for a minimum 3-Year Rated Solar Reflectance of 0.20 & a minimum 3-Year Rated Thermal Emittance of 0.75 (except for low-sloped roofs in Climate Zones 13 & 15 — very hot climates — need minimum 0.63 Solar Reflectance).
- Specify all wall construction at 2x6 framing, R-21 between studs, and R-4 Exterior Foam Board. This is now the standard construction for new homes. The energy budget is set using this wall assembly. Therefore, any design with less than 2x6 framing, R-21 + R-4 Exterior Foam Board is already behind in meeting energy compliance and other energy measures will be needed to balance the energy budget.
- Consider staggered 2x6 wall framing. Staggered wall framing provides a better thermal barrier.
- Consider Advanced Roofing Construction Types in climate zones with a cooling need:
- Continuous insulation above roof rafters; R-6 minimum with 1" spacing; R-8 minimum without air spacing.
- Below Roof Deck Insulation: R-38 at the ceiling over the sheetrock & additional insulation between the roof framing rafters: R-13 minimum with air space; R-18 minimum without air spacing. What about venting/air space? If need venting/air space, create a cavity to hold insulation (perhaps using some type of netting) at the bottom of the rafter, just under the required air space.
- Consider a Quality Insulation Inspection (QII) by a qualified HERS rater. For more information on QII please see link below.
See also:
- Changes in the 2016 California Energy Code, beginning January 1, 2017
- 2016 Energy Code Lighting Requirements
- What is a QII (Quality Insulation Inspection)?
As always, I am available to discuss the process of meeting the California Energy Code for any building project. Contact me …