Ceiling spray foam insulation in Blackfalds is for the parts of a house with no attic above them: a vaulted great room, the ceiling under a bonus room, a covered entry or a low-slope section between two roof levels. On the plans built in this town there are more of those than there used to be.
The great room ceiling on a builder's plan
Open vaulted ceilings sell houses, and they appear on a large share of the plans built here in the last twenty years. They are also the hardest assembly in the house to get right, because there is no attic above to work in, no space to add depth later, and a large surface at the warmest point in the building. Whatever that assembly received during construction is what it will have for the life of the house, which is why it deserves attention that a flat ceiling does not.
A truss that leaves no room at the edge
The detail that decides how one of these performs is where the ceiling meets the outside wall. A standard truss narrows to almost nothing at the bearing point, so the insulation gets thin exactly where the wall meets the roof and exactly where the ventilation path also has to fit. A raised-heel truss solves it and costs slightly more, so it is not always what got built. Where it was not, the corner of the room nearest the outside wall is the cold spot, and it is not a mystery, it is geometry.
Where the ceiling meets the outside wall
That junction is where the work concentrates. It is where the air seal has to be continuous, where insulation has the least room, and where any gap connects the room directly to the vented space above. On a Blackfalds house it is reachable from the attic side on the flat sections and much harder on a true vault, which is why the approach is settled by looking at the roof structure rather than by assuming from the room below.
What the builder chose, and whether it can change
A shallow or vaulted roof is either vented or unvented and it was built as one of those. Changing that decision after the fact is a real piece of work rather than an adjustment, so the first question is what is actually up there. Where a vented assembly has a clear continuous path that can be kept clear, it stays vented and the work is sealing and depth. Where the path was never viable, an unvented assembly with foam in continuous contact with the deck is the honest answer, and it is priced as the larger job it is.
Ceiling Spray Foam Insulation Blackfalds: Common Questions
Why is one corner of the great room always cold? That is usually the truss heel leaving no room for insulation where the ceiling meets the wall.
Can we add more insulation up there? In a vault there is nowhere to put it. The question becomes performance per inch and whether it is sealed.
Can a vented roof be changed to unvented? It can, and it is a real job rather than an adjustment. What is up there gets established first.
Size the assembly with the R-value calculator, then get a free Blackfalds quote. More on Ceiling Spray Foam Insulation Alberta.