A ceiling is easy to insulate when there is a roof space above it a person can crawl through. On Bow Island's older stock a surprising number of ceilings have no such space, and those are the ones that get complained about and never get fixed.
Ceilings with nowhere to work from
Three shapes come up repeatedly here. The low-slope roof over an addition, where the rafters sit almost flat and the cavity is four or five inches with no access at either end. The shallow hip roof on a mid-century bungalow, where the roof plane meets the wall with almost no heel height so the last two feet of the ceiling have nowhere for insulation to go. And the flat-roofed back porch or carport that was enclosed later and roofed over without anybody thinking about the ceiling at all. None of these can be topped up from above, because there is no above.
Why the edge of the ceiling is colder than the middle
On a shallow roof the insulation thickness tapers to nothing where the rafter meets the top plate. The middle of the room can be well insulated and the perimeter can have barely an inch, and that is exactly where the exterior wall is, so the cold shows up along the edges and in the corners. Adding depth in the middle does nothing about it. Foam sprayed into the assembly fills the taper to the end of the rafter bay and gives the edge something to work with, which is the whole reason it gets used on these roofs.
The join between the old roof and the new one
Where an addition was roofed into an existing house there is a line where two roof structures meet, and that line is almost never sealed. Sometimes the old wall is still standing inside the new roof space with its original siding on it, open at the top. Air moves freely between the two roof spaces and between both of them and the house. Finding that line and closing it is often worth more than any insulation added on either side of it.
Prairie sun on a shallow assembly
Bow Island takes long, clear, hot summer days, and a shallow ceiling assembly has no depth to buffer them. The roof surface gets far hotter than the air, there is very little material between it and the room, and in a low-slope cavity there is rarely enough space to vent properly. The result is a room that is noticeably hotter than the rest of the house from mid-afternoon onward. The same foam that closes the winter problem is the only thing that fixes the summer one, because the fix is thermal mass and air sealing in a space with no room for either.
Vented or sealed, and how to decide
A ceiling assembly either has a clear, continuous vented space above the insulation with intake and exhaust, or it has none and is insulated solid to the deck. Half of each is the assembly that fails. On these shallow roofs there is usually not enough depth to vent properly, so solid closed-cell to the underside of the deck is the honest answer, at a thickness that keeps the deck warm enough not to condense. We settle that before anything is sprayed, not after.
Working from inside when there is no other way
On a ceiling with no access the practical route is to take the ceiling finish down, spray the bays, and put a new ceiling up. That sounds drastic and on an addition with a stained, cracked ceiling it is often what was going to happen anyway. The alternative, where the finish is sound, is to work from the roof during a re-roof, which is the one other moment these assemblies are open.
Who does the work
Nobody gets handed your ceiling spray foam insulation Bow Island job. We quote the job, schedule it and stand behind it, and our crews are the ones who show up.
Ceiling Spray Foam Insulation Bow Island: Common Questions
Our addition is always the cold room. Why? Usually because its roof is shallow, the insulation tapers to nothing at the wall, and the join to the main roof was never sealed. All three are fixed from the same access.
Can you add insulation without taking the ceiling down? Only where there is a reachable space above it. On a closed low-slope cavity there is no way to verify coverage without opening it, and we will not claim a result we cannot see.
Does the cavity need to be vented? It needs to be clearly one thing or the other. If there is not enough depth for a proper vented path, the assembly is insulated solid to the deck.
How much does ceiling spray foam insulation cost in Bow Island? The foam follows area and thickness, but access dominates. Removing and replacing a ceiling finish is usually the larger half of the work on these assemblies.
How do I choose a ceiling spray foam contractor in Bow Island? Ask whether the assembly will be vented or solid when they are finished, and why. A contractor who has not decided that has not designed the ceiling.
Size the assembly with the R-value calculator, then get a free Bow Island quote. More on Ceiling Spray Foam Insulation Alberta province-wide.