After the energy crisis in the seventies, during Jerry Brown’s first term as governor, California started regulating the energy use of buildings. The structures that we live and work in consume more than 40% of all of the energy we use in our country, so making buildings more efficient was seen as an important step in reducing our energy use.
Back then the fear was that we were running out of fossil fuels, which were also increasingly under the control of foreign powers. Forty years later, we have the same concerns but are perhaps even more concerned about climate change brought about by CO2 releases into the atmosphere. Our energy practices are killing our planet.
In response to this situation, California’s energy regulations, colloquially known as Title 24, are about to get their most major revision in forty years, according to Mark Madison of Energy Code Works, our wonderful title 24 consultant. The revisions were due to take effect on January 1st, along with changes to the building code, but title 24 section has been delayed until July 1st.
The changes are many and quite detailed, but here are some highlights:
General goal: the average house is to exceed 2005 title 24 standards by 35%. By comparison, currently Build-It-Green expects houses to be a minimum of 15% better than 2005 standards.
Any change to the exterior envelope, even a new window, will now requires that a title 24 report be done. Previously, it was only required if more floor area was being added.
Furthermore, a detailed Home Energy Rating System (H.E.R.S.) report indicating the existing condition of the house’s envelope will be required unless one wants to use very high default values in the title 24 calculations. No more guessing about whether your existing house has insulation in the walls.
Building Envelope Design:
Exterior walls. Minimum R-19 insulation with 2x6 studs. 2x4 stud exterior wall construction will only work if rigid board insulation is added to the outside face of the wall.
Roofs: minimum R-30 insulation (R-19 for remodels). Radiant barriers in the roof sheathing or in the attic will be required.
Raised floors: minimum R-19 insulation.
Windows and Exterior Doors: minimum average u-factor of .32, maximum average SHGC of .25, with only very minor exceptions. You can pretty much say good-bye to single pane glazing. Windows MUST have NFRC labels certifying that they meet these requirements or very high default values are used in the calculations – so maybe say good bye to custom made windows by small manufacturers.
A minimum of 250 square feet of ‘solar ready’ un-shaded, properly orientated, structurally sound roof must be provided for solar panels. We were told that solar access will trump trees, if existing vegetation shades all of the roof areas. One can imagine this will be very challenging to enforce, particularly if the shading trees are on someone else’s property (not to mention the problem in urban areas when it is other buildings which shade your house..).
Heating and Cooling System Efficiency:
Minimum 80% AFUE (was78%)
Minimum 14.00 SEER (was 13.00)
Minimum 11.7 EER (was 10.0)
This was described by Mark Madison as one of the biggest changes:
Duct sealing will be mandatory and HERS testing will be required in all new construction if ducts are not run inside of conditioned spaces.
Minimum return air duct sizes will be enforced.
Any change to the heating equipment in an existing house will require a HERS test.
Duct systems should be designed before the title 24 calculations are done to get extra credit.
So, say goodbye to poor workmanship and leaky ducts.
The title 24 reports which we have generated for our projects will use new software and produce a whole new range of forms and certificates.
These changes are supposed to make our houses 25% more energy efficient. Another 25% jump in efficiency is slated to be required in 2017, along with a final 25% jump in 2020, at which point a new house in California is supposed to achieve ‘net zero’ energy use, that is, it uses no more energy than it produces (through photo-voltaic panels, water heating panels, natural heating). Sounds like an ambitious goal, but a necessary one.