Similar rigs, similar guns, two spray foam insulation products whose behaviour diverges enough that picking the wrong insulation is a failure rather than a trade-off.
It comes down to the bubbles. Closed cell has sealed ones holding gas. Open cell has broken ones holding air.
Call +1 506-300-4863 and describe the space, and you will get a straight answer on which one it needs.
Closed cell runs roughly R-6 to R-7 an inch, easing toward R-6.5 as it ages. Open cell runs roughly R-3.5 to R-3.8.
Closed cell is its own vapour barrier at sufficient thickness. Open cell is not a vapour barrier at any thickness, and no amount of extra depth makes it one. That single line decides most specifications.
Both are air barriers.
Closed cell is rigid and adds structural stiffness. Open cell is soft and flexible.
Open cell absorbs sound well. Closed cell is dense and transmits it.
Open cell costs meaningfully less per unit of volume.
Anything below grade needs closed cell, including foundation walls, crawl space walls, and anywhere in contact with or near the ground.
Rim joists and headers need it too, because the assembly there is thin and fully exposed.
Under a roof deck, the vapour control has to sit at the cold side, which calls for closed cell as well.
Anywhere the depth available is limited, the R-value has to come out of a shallow cavity, so closed cell is the only way to reach it.
Anywhere moisture is already a known problem also calls for closed cell. In a fog belt, that is a longer list than it would be inland.
Interior partition walls are a good fit, because the job there is sound control rather than heat.
Between storeys, open cell works for the same reason.
Deep, irregular cavities well inside the heated envelope also suit open cell, because the extra volume is cheap to fill and there is no vapour control requirement.
Attic roof decks sometimes take open cell too, though whether that is appropriate depends on the roof and on the vapour control strategy chosen.
Used in the right place, it is the better value. Used against a foundation, it is a mistake that shows up as damp within a year.
A flash and batt or flash and fill assembly uses a shallow layer of closed cell against the sheathing to do the air and vapour control, then fills the rest of the cavity with something less expensive.
It is often the best value in a new wall, and it is worth asking about rather than accepting a full-depth quote by default.
Describe what you are dealing with and we will name the insulation that belongs there, including when the cheaper one is correct.
See the full range of spaces we insulate on the home page.
Call +1 506-300-4863.
We install spray foam insulation on roofs, foundations, floors, outbuildings and commercial decks throughout the region.
No single surface on a building loses more heat than the one over your head, and none is cheaper to put spray foam insulation into. In a tall house it is worse again, because air rising through three storeys reaches the ceiling with real force behind it.
View Attic Insulation
A cellar is the one part of a building that is cold, damp and connected to everything above it at the same time. Left without spray foam insulation it drags the ground floor down and pushes moist air up through the house.
View Basement Insulation
A crawl space is a cellar nobody can stand up in, which is exactly why its insulation gets ignored. The floor above it is cold, the air in it moves up into the house, and almost nobody has looked at the insulation in years.
View Crawl Space Insulation
Two separate problems get called garage insulation, and spray foam insulation answers both. One is wanting the garage itself usable. The other is the cold room sitting above it.
View Garage Insulation
Open framing is the cheapest opportunity anybody gets to install spray foam insulation properly, and it lasts a few weeks. Every insulation decision after boarding is more expensive and less effective.
View New Construction Insulation
Two reasons insulation comes out. Either it has failed on its own over decades, or somebody installed spray foam insulation badly and it never worked.
View Insulation Removal and Replacement
Warehouses, workshops, shops, offices above shops, and the parts of an industrial building where the temperature actually has to hold. Larger surfaces, harder access, and a schedule that has to work around a business that is still running.
View Commercial and Industrial InsulationBook a spray foam insulation assessment. The space gets measured, the substrate gets read, and the insulation price you receive is the price you pay.
Tell us the type of space, the approximate size, whether anything heats it today, and what the insulation in it is failing to do. Prefer to talk it through? Call +1 506-300-4863.
