What is the best attic insulation for Northern California?

Two of the most energy efficient insulation options are cellulose and spray foam insulation. Cellulose insulation in Northern California is made up primarily of recycled fibers like newspapers, along with additional components designed to repel insects and reduce the flammability of your insulation.

Does attic insulation help in summer?





A properly insulated attic can benefit your home in many ways, beside just keeping the home at a comfortable temperature year round. The short answer, yes, insulating the attic is an effective way to keep your home cooler during the summer months.

What type of insulation is best for attic?

Spray foam offers the best attic insulation performance available. Choose from two types: closed-cell and open-cell, aka 2-pound and ½-pound, respectively. They sport insulation values of approximately R-6.5 and R-3.6 per inch, respectively.

Is adding insulation to attic worth it?

Installing attic insulation this winter is a worthwhile long-term investment because it can significantly decrease your heating bills. As an added benefit, when the hot D.C. temperatures come back, the attic insulation will also minimize your air conditioning bills.

How do you insulate attic in hot climate?

There are two main types of insulation used in attics. In a hot climate zone like southern Arizona, for example, we typically recommend blown-in fiberglass and radiant barrier. Blown-in fiberglass insulation provides a dense, effective barrier against heat loss that is also among the greenest insulation options.

Which is better cellulose or fiberglass blown-in insulation?





At 3.5 per inch of material, the R-value of blown-in cellulose is 23% better per inch than fiberglass batts! According to research done at the Oak Ridge National Lab, fiberglass loses up to 50% of its R-value in very cold conditions; making cellulose a better choice for homes in northern climates.

How can I keep my attic cool in the summer?

Install electric ventilators and attic fans, which remove hot air from an attic. They have thermostats that turn the fan on at a recommended preset temperature of 100-110 degrees. Alternatively, install passive vents such as gable, soffit and ridge vents, which are openings in the roof that allow hot air to escape.

How hot is an attic on a 90 degree day?

125 degrees

More often than not, attic temperatures will be in excess of 125 degrees on a 90 degree day. This will overwork your air conditioning equipment, run up your utility bill and shorten the life of your roof. Ridge vents help – excessive heat can escape through ridge vents.

What insulation keeps heat out?



Fiberglass is the most common type of insulation used for residences because it is by far the best, particularly for hot climates. Here’s why: Fire-retardant – Fiberglass insulation is fire-retardant, making it an ideal choice for homes in dry climates and areas prone to fire.

Is attic radiant barrier worth it?

Radiant barriers are more effective in hot climates than in cool climates, especially when cooling air ducts are located in the attic. Some studies show that radiant barriers can reduce cooling costs 5% to 10% when used in a warm, sunny climate.

Should you insulate attic roof rafters?

Insulating between rafters will do no good, because the attic should be ventilated, and the rafter insulation would be between two unheated spaces. You can add insulation to the floor; the more the merrier. Just don’t put it in the eaves. Also, make sure the attic is well ventilated.

Should I insulate my attic floor or ceiling?



roof insulation is no-contest. The floor wins every time. Insulating the floor is standard practice for an unfinished attic space. The exception to this rule takes place when families opt to convert an unfinished attic space into something usable or livable.

Do you need attic insulation in California?

That’s where this nifty EnergyStar chart comes in handy. Sacramento and most of California are in Zone 3, which requires attic insulation with an R-value between 30 and 60.

Should I remove old attic insulation before adding new?

Expert contractors that specialize in insulation advise that removing old fiberglass insulation is best before installing new cellulose insulation because of possible mildew, mold, or rodent excrement.

How often should attic insulation be replaced?

15-20 years



However, due to its construction with natural materials, eventually the product will lose effectiveness. Fiberglass insulation typically needs to be replaced 15-20 years into it’s life, as it can easily become dirty, wet, moldy, and ineffective if there’s a roof leak or water damage of any kind.

Can you add too much insulation to your attic?

It’s possible to over-insulate an attic as too much will cause moisture buildup and eventually result in mold. Eventually, adding more insulation leads to diminishing returns in trapping heat as well.

Can you put insulation over old insulation?

Yes! You can absolutely new insulation over old insulation… as long as it isn’t wet. Energy Star advises as follows: “If it… appears that the insulation [is wet or] has previously been wet, you should look for the cause and repair the problem to prevent a reoccurrence.