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The two-pound foam
Closed Cell Spray Foam in Ottawa
The densest foam we install: the highest R-value per inch of anything on this site, and its own moisture barrier in the same application.
What Makes It Different
Closed cell spray polyurethane foam cures at roughly two pounds per cubic foot with each cell sealed from its neighbour. That dense structure is where every advantage comes from: around R-6 to R-7 per inch, the highest of anything we install; a built-in vapour retarder, because water cannot travel through sealed cells; and genuine rigidity, since cured closed cell bonds to the substrate and stiffens the assembly.
It costs more per board foot than open cell. In the right assembly that is worth paying; in the wrong one it is not, and we will tell you which you have.
Where Ottawa Needs It
Below grade and anywhere moisture is in play. Foundation walls, crawl space perimeters, rim joists, the underside of a floor over unconditioned space, and steel building decks where condensation forms. In every one of those a water-absorbing material is a failure waiting for a wet spring.
The second reason is depth. A standard stud bay gives you a fixed space, and filling it with closed cell puts meaningfully more R-value in that same cavity than a lower-density product would. Where the cavity is deep and dry, open cell usually wins on value instead.
A Long Heating Season Changes the Maths
Ottawa runs one of the longer heating seasons of any major Canadian city, and that is the condition the envelope has to be built for rather than an average. The more extreme the design condition, the more the R-per-inch advantage is worth in a cavity you cannot make any deeper.
Find out which foam your assembly needs: call (613) 777-0096 or request a free estimate.
Foam Is Not a Cure for Water
Closed cell does not absorb water, which is exactly why it belongs below grade. What it will not do is fix a water problem. If there is standing water, a failed ground barrier, or grading driving rain at the foundation, that gets dealt with first and it is named in the written scope.
Insulating over an active leak is covering a problem rather than solving it, and it is the kind of job we would rather not take than take badly.
Closed cell questions
What people ask before choosing it
Is closed cell worth the extra cost?
In the right assembly, yes. Below grade, in a crawl space, on a steel deck, or anywhere depth is limited, it is the correct product. In a deep, dry cavity where you want maximum coverage per dollar, it is not the best value and we will say so.
How many inches do I need?
It depends on the assembly, which is why the estimate names an installed depth for each area rather than one number for the house. At roughly R-6 to R-7 per inch it reaches a target in fewer inches than anything else we install.
Does it really add strength?
Cured closed cell bonds to the substrate and stiffens the assembly. It is a genuine secondary benefit, particularly on metal buildings. It is not a structural repair and we will not sell it as one.
Will it trap moisture in my walls?
That is the right question. Because it is vapour-closed it changes how an assembly dries, which is why we look at which direction a wall needs to dry before specifying it. In the wrong assembly any vapour-closed product can cause problems. That is a design decision, not a product flaw.
Can you mix closed cell and open cell?
On a whole-house job that is often the best value: closed cell where moisture or limited depth demand it, open cell across the large open areas. Mixed specifications are itemised so you can see what goes where.
Not sure which foam your assembly needs?
Tell us about the space and we will specify the product that suits it, with the reasoning in writing.
Free written estimates • Installed depth stated • Mixed specifications itemised
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