California Attic Insulation R Value

If kraft or foil faced insulation is used it should be installed per manufacturer recommendations to minimize air leakage and avoid sagging of the insulation.

California attic insulation r value.

Insulation leakage radiant barrier r 30 at ceiling attic floor r 38 at ceiling attic floor fiberglass below roof deck between rafters air handler ducts in the attic option b 1 r 6 or r 8 depending on cz all with 5 leakage 2 3 5 7 10 16 r 13 4 8 9 11 15 r 19 air handler ducts in conditioned space option c 1 16 r 6 all with 5 leakage. Batt insulation should fill the wall cavity evenly. Add insulation to attic. In fact there are building codes that require a certain r value for insulation depending on where in the country you live.

Our r value cognitive dissonance. Zones 2 and 3 r30 to r60. What i m talking about is a house with ducts in unconditioned space especially an unconditioned attic. If we put ducts in unconditioned space.

Existing 3 4 inches of insulation. The higher the r value the better the thermal performance of the insulation. Your home s age if your home is more than 10 year old you likely need more insulation. Minimum insulation r value requirements non residential above roof deck.

I m in georgia iecc climate zone 3 where our current state code requires r 13 in exterior walls r 18 in attic kneewalls r 19 in floors and r 30 in ceilings. The insulation must also meet the manufacturer s specified minimum weight per sq ft. There are many ways to retrofit a home with fiberglass and. As you can imagine the r value for insulating an attic in alaska isn t necessarily going to be the same for insulating an attic in california.

You will need a higher r value of insulation if you live in the northeast than if you live in southern california. You can achieve better thermal performance in your attic by adding an additional layer of insulation. For the corresponding r value. That s where this nifty energystar chart comes in handy.

Achieving greater r values in exterior walls. Recommended insulation levels for retrofitting existing wood framed buildings. Sacramento and most of california are in zone 3 which requires attic insulation with an r value between 30 and 60. Zone 1 for example should have attic insulation of r30 to r49.

State applicable energy ashrae zone minimum r value state local ms mississippi ashrae 90 1 2010. Zone 4 r 38 to r 60. As a benchmark one inch of solid wood has an r value of 1. And zones 5 through 8 need r49 to r60.