Spray Foam Insulation in San Angelo, TX

Spray foam insulation works best in San Angelo where heat and air leaks meet: under the roof deck above attic ductwork, inside steel buildings, in walls opened during a remodel, and in cramped spots where loose fill will not stay put. Foam goes on as a liquid, expands into gaps and cures in place, so one layer handles both insulation and air sealing. We spray two kinds, and choosing between them is the first decision on any job.

Closed cell vs open cell

Open-cell foam cures soft and spongy. It expands roughly to fill a rafter bay, seals air very well and dampens sound. HomeGuide rates it at R-3.5 to R-3.7 per inch, and it costs less per inch of thickness. Water vapor can pass through it, which in a dry climate is often a feature: it lets a roof deck dry if a small leak ever happens, so the leak shows up instead of hiding.

Closed-cell foam cures hard and dense, at R-5 to R-7 per inch according to HomeGuide. At normal thickness it slows vapor, sheds water and adds stiffness to what it is sprayed on. It costs more per square foot but packs more R-value into less space. That makes it the pick for metal buildings, garage ceilings under bedrooms, cantilevered floors and anywhere a cold or damp surface meets warm air.

Moving the attic inside

Most San Angelo houses have ducts and often the air handler in the attic. On a 100-degree afternoon that attic gets far hotter than the air outside, and every leaky joint in the duct system pushes cooled air into it. One fix is to bring the insulation line up to the roof: spray open-cell foam on the underside of the roof deck and gable walls, close the attic vents, and the ductwork ends up in a space that stays near house temperature. It costs more than blowing in loose fill, but on houses with a lot of duct in the attic it can be the better long-term plan. We explain what that involves before quoting it, including the code's thermal or ignition barrier rules for the space.

R-value targets in Zone 3

Tom Green County is classified as Climate Zone 3B. Texas still uses the energy chapter of the 2015 International Residential Code statewide, and in Zone 3 its prescriptive table lists R-38 for ceilings, R-20 or R-13 plus R-5 continuous for wood-frame walls, and R-19 for floors. On a roof deck, those numbers set how thick the foam needs to be, and that thickness drives the price. We write the planned thickness and the R-value it reaches on every quote, so you can compare bids on the same terms.

Where foam is the wrong choice

Foam will not fix a leak. If water is getting into the attic or a wall, the source has to be repaired first, or foam will hide the damage until it is expensive. On a wide-open attic floor, sealing the gaps and blowing in fiberglass or cellulose usually reaches the same R-value for much less. Old wiring, vermiculite that may contain asbestos and active pest problems get checked before anything is covered. If we find any of those, you hear about it before you get a price.

Preparing for spray day

We cover floors, mask windows and fixtures, and set up ventilation before spraying. HomeGuide recommends leaving the house for at least 24 hours while foam cures; for a detached shop it may not affect the house at all. In summer we start attic work early, because a San Angelo attic by mid-afternoon is too hot for safe work and for some foam products. Once cured, foam does not settle, so the thickness we leave stays put.

Tell us which spaces you are thinking about and what bothers you, whether that is a hot upstairs room, high summer bills or a shop that sweats. We will look, explain where foam pays off, and send a written price. Get a free estimate