Owens Corning Attic Insulation Nationwide

Owens Corning Attic Insulation: The San Francisco Owner’s Guide

We install Owens Corning attic insulation in San Francisco homes, and most full-attic projects run between $2,200 and $5,400 depending on square footage, existing insulation condition, and access. We carry Owens Corning fiberglass batts and blown-in options on our trucks, and we can typically start within a week of your written estimate. Most San Francisco homeowners call us after noticing a bedroom that won’t hold temperature, a spike in the PG&E bill, or the telltale sign of old insulation settling below the floor joists.

Call (341) 247-0222

Thistledown Insulation San Francisco is an independent installer, not an Owens Corning dealer or affiliate. That matters because we install what your attic actually needs, matched honestly to how your house behaves in San Francisco’s marine-layer climate.

Which Owens Corning Models This Applies To

Owens Corning attic insulation spans several product lines, and the right match depends on what is already up there and what the house needs. The three most common in San Francisco attics are:

• Owens Corning EcoTouch PINK Fiberglas batts – available in R-13, R-19, R-30, and R-38. San Francisco’s mild climate means R-38 is the usual target for flat-ceiling attics, while sloped ceilings in older Victorians often max out at R-30 due to cavity depth.
• Owens Corning AttiCat blown-in fiberglass – sold as expanding bags, blown to a chosen depth. This is what we use most often in San Francisco’s older homes, because it fills irregular joist bays and settles predictably.
• Owens Corning ProPink blown-in fiberglass – a denser, higher-performance blown product typically used when we are topping off existing insulation to hit a specific R-value.

One compatibility gotcha we see often in San Francisco: if your attic has old rock wool or vermiculite, Owens Corning blown-in fiberglass can sit on top of it, but you need a moisture evaluation first. In fog-belt neighborhoods like the Sunset and Richmond, condensation on the underside of the roof deck can wet the top layer of old insulation. Burying moisture under new Owens Corning fiberglass makes the problem invisible for a year, then it shows up as a cold, damp ceiling below. We check before we quote, and never bury a problem to hit a square-footage number.

Signs Your Owens Corning Attic Insulation Is Failing

• Rooms that swing wildly between morning and evening. Old Owens Corning batts compress over time. Once a batt loses its loft, the R-value drops with it, and the room below becomes a thermometer for whatever the attic is doing that hour.
• A bill that climbs without a behavior change. Heat rises. When attic insulation loses effectiveness, the furnace works harder in winter and the house drinks power in summer. If your PG&E bill is up 15 to 20 percent with no new appliances, the attic is the first place we look.
• Specific cold spots on the ceiling. This shows up as visible ghost lines or a ceiling that feels colder near the perimeter. It usually means batts were cut poorly around recessed lights, plumbing vents, or the attic hatch, and cold air is pooling at those gaps.
• Dust around ceiling fixtures and cobwebs that appear fast. Deteriorating Owens Corning fiberglass sheds tiny particles that find their way through light-fixture gaps. It is not dangerous at normal levels, but it is a sign the product is past its useful life.
• You can see the joist tops. Building code in San Francisco calls for insulation to sit above the joists, not flush with them. If you climb up and see the framing beams, the installed depth is below spec, and the house has been under-insulated the whole time.

Each of these gets clearly worse in older San Francisco homes, where attics are irregular and insulation was often installed once, decades ago, and never touched again.

Replacement Cost & What’s Included

For a typical San Francisco flat-ceiling attic of 800 to 1,200 square feet, plan on $2,200 to $5,400 installed. Smaller attics in condos or Mission District flats can land around $1,800, while large homes with sloped ceilings, awkward joist spacing, or existing insulation removal run higher.

What drives the range:

• Square footage and attic accessibility (pull-down ladder vs scuttle hole changes labor)
• R-value target (R-38 vs R-49 changes material cost by roughly 20 percent)
• Existing insulation condition (removal and disposal adds cost; topping off costs less)
• Air sealing (we recommend it on nearly every San Francisco attic, and it is a separate line item)

Every quote is a written number before we touch a rafter, and that number includes labor, materials, shoe covers, drop cloths, and a photo of the cleaned-up attic before we leave. We back every Owens Corning installation with our 365-Day Done Right Promise. If it is not right, we make it right.

DIY or Call Us?

Fiberglass batts are not spring work, and you will not get hurt installing them, but getting the R-value right in a San Francisco attic is harder than it looks. The honest split: you can absolutely measure your joist depth and square footage yourself, and doing that before you call us saves everyone time. What goes wrong on the DIY side is cutting batts around old wiring, leaving gaps at the eaves, and missing air leaks because you are working from the top down instead of the bottom up.

Also worth saying plainly: blown-in fiberglass requires a machine, and renting one usually means the blower sits in the driveway while the hose kinks in the attic hatch. We do this weekly. If you want to get the measurements and let us do the rest, call (341) 247-0222 and tell us what you found.

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