Energy Questions and Concerns
All I am doing is replacing same size windows throughout my residence to gain higher energy efficiency. Is there any code regulations I should be concerned about in replacing my windows?
Yes. The following window and window glazing requirements must be complied with:
- There are window locations within the residence that are considered as “hazardous locations”, and therefore, require safety glazing in compliance with section R308, I.R.C. The glazing must be listed and labeled as safety (“tempered”) glazing. The “hazardous locations”, within a residence, are listed in section R308.4, I.R.C.
***Please note: If the existing window glazing was not originally safety glazing and the existing window is located in a “hazardous location”, the new replacement window (glazing) must comply.
- Ensure that the replacement windows in the bedrooms are of the operable type, with clear openings to meet or exceed the minimum required “emergency escape and rescue opening” size, reference section R310, I.R.C.
- To meet the minimum natural ventilation requirements of section R303, I.R.C., ensure that the replaced operable windows remain operable.
- The replacement windows must have a U-factor (refer to Energy Code Terms for definition) of 0.40 or better and a maximum SHGC of 0.25 (refer to Energy Code Terms for definition), reference Table N1102.1.1, I.R.C.
To encourage energy efficient "hot water on demand", some jurisdictions require an electrical receptacle outlet under each bathroom lavatory. Is this a requirement in your City?
Yes. The City has amended the code to require a 125-volt, 15 ampere-rated GFCI receptacle outlet in an accessible location under each bathroom lavatory to allow for the operation of a point-of-service hot water re-circulating pump. Note: If a central hot water re-circulating pump is installed at the time of the final inspection, the outlets will not be required. See City amended section E3901.6, I.R.C.
I am building a bedroom addition to my residence. What is the minimum amount of insulation required in the new ceiling (with attic above) and in the wood frame exterior walls?
The City is in “climate zone 2B”, therefore a minimum added insulation "R-value" (refer to Energy Code Terms for definition) of R-38 is required in the ceiling (w/ attic above) and a minimum added insulation “R-value” of R-13 is required in the new wood frame exterior walls, reference Tables N1102.1.1 and N1102.1.3, I.R.C. Also see sections N1102.1.2 and N1102.1.3, I.R.C., for permitted “alternative” insulation solutions.
In addition to the maximum required U-factor for installed glazed fenestration (windows/glazed doors/skylights) in new construction, the code now requires a maximum "SHGC" rating for all glazed fenestration. What is "SHGC", what does it measure and what is the maximum "SHGC" allowed?
“SHGC” stands for “Solar Heat Gain Coefficient”. The technical definition for “SHGC” is the ratio of the solar heat gain entering the space through the fenestration (refer to Energy Code Terms for definition) assembly (window/glazed door/skylight) in comparison to the incident solar radiation.
The term “solar heat gain” in the ratio includes directly transmitted solar heat and absorbed solar radiation which is then re-radiated, conducted or convected into the space. Another way to say it, is that “SHGC” measures how well a fenestration assembly blocks heat from the sunlight. “SHGC” is expressed as a number between 0 and 1. The lower the “SHGC”, the less solar heat the assembly transmits. The maximum “SHGC”, the energy code allows for new construction in "climate zone 2B", is 0.25.
I have been told that all new construction will now require a posted energy certificate. Is this true?
Yes. The City will require that the contractor of record posts a permanent certificate listing the R-value (refer to Energy Code Terms for definition) of all insulation installed, and the U-factor plus solar heat gain coefficient (SHGC) of all installed fenestration (windows/glazed doors/skylights).
The City’s “Energy Compliance Certificate” form will be given out at the time of building permit issuance and will be required to be filled out, signed by contractor and a signed copy given to both the City and the homeowner for record keeping.