What closed-cell actually is
Closed-cell foam cures into a dense, rigid material whose cells are sealed. That structure is what gives it its three distinguishing properties: it sheds bulk water, it adds structural rigidity to whatever it is bonded to, and it delivers more thermal resistance per inch than open-cell.
Those properties cost money, so it is specified where they earn it. What decides that is the assembly, which is the same logic the specification walkthrough follows on every job.
Detail
Where it is the right choice
- Against steel panelsMetal buildings and barndominiums. The panel stops being an exposed cold surface, so condensation has nowhere to form.
- Crawl spaces and rim joistsAnywhere water contact is possible.
- Where moisture is the problemMoisture first, heat second.
- Low-slope roofing assembliesUnder a protective coating, as a seamless roof system.
- Where rigidity helpsIt stiffens the assembly it bonds to, which matters on a building that moves.
- Tanks, vessels and pipeIndustrial thermal work, applied to a client specification.
Why it matters so much on steel
Steel conducts heat quickly and holds no moisture. On a humid Houston night, the underside of a metal roof panel drops below dew point and water condenses on it. In an uninsulated shop that is a nuisance. Over stored goods or a bedroom ceiling it is a leak with no hole in the roof.
Closed-cell sprayed directly against the panel removes the exposed cold surface entirely. Indoor air stops reaching the steel, so the condensing surface is gone.
Batt between the purlins leaves the problem in place. It sags, it leaves the purlin as a continuous thermal bridge, and it traps moisture against the panel. The same reasoning applies to a barndominium, with living space underneath raising the stakes.
Questions
Common questions
Each has its place. Closed-cell costs more per square foot and open-cell damps sound better, so on an attic roofline in a house open-cell is usually the better answer. Closed-cell earns its price where water, steel or rigidity are involved.
It can, and sometimes it is the right call — but in most Houston houses open-cell does the job at the roofline for less. We will tell you which we are proposing and why.
It bonds to the substrate and stiffens the assembly, which is a genuine and well-known property of the material. It remains an insulation product, and structural questions still belong with an engineer.
The visit is free. Someone comes out, looks at the building and gives you a written scope and a price, and the decision stays yours.
48 cities across the eight-county Houston–Galveston region — Harris, Fort Bend, Montgomery, Brazoria, Galveston, Chambers, Liberty and Waller — plus five extended project markets.
It depends on the product and the thickness. For scale, a Department of Energy Building America photo shows 3 inches of closed-cell foam rated R-19. The product's technical data sheet gives the tested value per inch, and our scope states the applied depth.
It is a vapor retarder, not a Class I vapor barrier. The Department of Energy's Building America guidance states that 2 inches of closed-cell foam "is typically a Class II vapor retarder," so it slows water vapor. That, and its resistance to moisture and air leakage, is why we use it where water contact is possible.
Our main closed-cell foam is Accufoam CC-HFO. Its data sheet lists R-7.5 at 1 inch and R-24 at 3.5 inches. We also spray Profoam ProSeal. The product for your job is named in your written scope.
Get it looked at properly
One visit, a written scope, and a written price.
(832) 737-0787Greater Houston, plus extended project markets.