CALIFORNIA ENERGY COMMISSION - Blueprint Newsletter, September 2022

[mtnelect]

The most significant change in the
2022 Building Energy Efficiency
Standards (Energy Code) affecting
single-family residential buildings
is a prescriptive heat pump
baseline for either water heating
or space heating, depending on
the climate zone. The ventilation
requirements are strengthened to
improve indoor air quality. There
are new requirements and revisions
for additions and alterations. The
definition for single-family buildings
in § 100.1 is updated.

 

[__dan]

Sounds good. Heat pump DHW are very popular for energy savings with the only drawback being slow recovery time. So if you have 8 people in the household taking sequential showers to get to work or school, you would need either CH4 gas or deodorant. But the 8 person household is kind of a 1960's problem, so moot, unless it's 8 people unrelated working menial task labor jobs sheltering together, then they'll tell you it's a zoning violation, not a building code one.

Heat pump DHW also dehumidifies and dumps the waste cooling into the envelope while heating DHW, so it's a threefer for many applications.

Fresh air also in on the right track. Some are making the mistake of building too tight, which is completely unnecessary.

No need to redefine the single family unit, I can do that for you. To do it right today imo would be extensive thermal mass (the concrete of the structure) inside of the insulated vapor barriered envelope. That's rigid foam board under the slab and exterior of the foundation, 2" is good but if you do 2" you will want 4" on the next build. Then the thermal mass is a battery and flywheel for heat from day to night to day. That by itself I would guess is 20 btus / sf less that conventional stick framed fiberglass in the cavity walls (not to mention the basement being a source of moisture and a sink for heat).

Then do not redefine the unit, make them not qualifiable for a mortgage (unsaleable) unless they meet the newest requirements, indicated above.

Then you would get massive employment as everything needs to be rebuilt on credit (the Sisyphean task) while the existing stock gets massive deflation (all cash sales only at the liquidation price).

You just have to identify the problem and then hit it hard enough.

 

[mtnelect]

Things have been changing in California ever since Title 24 was passed in 1975, but now things have really accelerated. In HVAC we used to ask the customer how many square feet do you have ? Then divided it by 400 to determine the size of the unit. Now, it is required to do a "Heat Load" study, which is lot more accurate than just a "Rule of Thumb" guess estimate.

 

[__dan]

From there just identify and eliminate the weak links (roof would be earth, earth sheltered home with galv steel siding).
Exposed exterior wall envelope could be rigid foam board, then 2' Roxul, then galvalume steel, would get it closer to riding through the firestorm season.

 

[__dan]

Rule of thumb would go from 35 btus / sf to 10 btus / sf. Then baselayer and fleece sweaters if the boiler / heat source cannot keep up.