Retrofit insulation in Alhambra CA - an older home that stays cooler upstairs

Many older houses around here were built with little or no attic insulation, and what's up there now has often settled, been crushed by storage or been laid over gaps nobody sealed. What moves the price is the size of the attic, how many inches are already up there, whether old material has to come out first through insulation removal, and whether the walls get done too. The schedule usually turns on what we find before we start, because old wiring, unrated can lights or vermiculite can mean a step that has to happen first. I'll look at all of that at the estimate, and that's where you get the figure for your own house.

Before anything goes in, I go up into the attic and look at what's there, because older homes are where we most often find old wiring, recessed lights that aren't rated to touch insulation, and vermiculite, and what I find decides whether the attic, the walls or both should come first. If the old insulation is wet or full of droppings, it comes out, because new material laid over it only hides the problem. In the attic we start with air sealing, closing the gaps around pipes, wires, can lights and the hatch, so the new insulation isn't fighting a draft. Then we lay down blown-in insulation, loose fill blown through a hose, evenly across the attic floor, keeping it full at the edges and the eave vents clear so the attic can still breathe. If the walls are part of the plan, we do them once the attic is settled.

Retrofit work overlaps with the rest of what we do. Spray foam insulation costs more and seals air while it insulates, and I recommend it when the ductwork runs through the attic. For most houses, sealing the gaps and topping up with loose fill is the better value, and that's the heart of our attic insulation work.

The state rule that matters most here is about attics. The California Energy Commission's guidance says its attic insulation and air sealing requirements apply when the ceiling under a vented attic is altered, and adding new insulation or replacing the old can count as altering it. That's one more reason we don't treat an attic retrofit as a quick top-up, and why the sealing and the insulation are planned together from the start.

Most of our calls here come from older houses with hot upstairs rooms or a room over the garage that never cools off, and the attic usually tells the story once I'm up the ladder. We're based in Alhambra and work in many cities around it, and we see the same kinds of houses on jobs in Monterey Park and San Gabriel. If your city isn't listed on our site, please ask.