Bonus room spray foam insulation in Drumheller is a smaller category than it is in commuter towns, because about 76% of the housing here predates 1991 and a coal-era valley cottage does not have a room over the garage. Where this job does appear it is on the newer building: houses on the upper terraces and the rim, infill on the larger lots, and the occasional substantial addition over a attached garage on an older property. Those few rooms misbehave more than the rest of the house, and they do it for reasons specific to where they sit.
A room with its envelope on five sides
The reason a bonus room is the worst room in any house is geometric. A bedroom in the middle of an upper floor touches outdoors on one or two faces. A room over a garage touches outdoors on both end walls, both sloped ceiling faces, and underneath, because the garage below is unheated. That is five surfaces where a normal room has two, and it is served by the same duct branch the designer gave a normal room. No amount of thermostat adjustment fixes an area that has two or three times the heat loss per square foot of everything the system was sized for.
Why the floor is the first surface here
In most of Alberta the sloped ceilings get blamed. In Drumheller the floor over the garage usually deserves it. The garage door is the largest uninsulated panel on the house and it is opened to the outside several times a day, so the garage is effectively outdoors with a lid. Batt installed in that floor cavity is normally sagging away from the subfloor within a few years, leaving an air space directly under the finished floor, and air moves freely through that space from the garage into the rim and up the end walls. Closed-cell sprayed to the underside of the subfloor adheres to it, fills the joist bays around the bridging, seals the rim at both ends, and leaves no gap for garage air to travel in.
Exposure on a rim lot
The houses that have bonus rooms here tend to be the ones sitting high, on the benches and the plateau above the valley, and that is the windiest ground in the municipality. There is nothing upwind to slow the air down, so the end walls of a bonus room on an exposed lot are being pressure-washed by wind for days at a time. Wind does not just cool a surface, it drives air through any gap in it, and a bonus room has gaps in abundance where the sloped ceiling meets the knee wall and where the knee wall meets the floor.
The day-to-night swing
This is semi-arid country with a very wide temperature range. The record high in Drumheller is 40.6 degrees Celsius, set in July 1941, and the record low is minus 43.9, set in January 1996, and the daily swing on an exposed site is large in both seasons. A bonus room with a south or west face and a vented roof above it will overheat in the afternoon and be cold by morning in the same twenty-four hours. Sealing the assembly flattens that, because most of the overheating arrives as hot attic air pulled into the room through the knee wall rather than as conducted heat.
What we spray and in what order
Underside of the floor first, including the rim at both ends. Then the knee walls and the junctions above and below them. Then the sloped ceiling, where closed-cell at roughly R-6 to R-7 per inch does the most work in the limited depth a rafter gives you. Open-cell at around R-3.5 per inch is the better choice on the wall between the room and the rest of the house if quiet is part of the goal. We quote the job, schedule it and stand behind it, and this is one of the few jobs where a small scope reliably changes how a room feels.
Bonus Room Spray Foam Insulation Drumheller: Common Questions
Why is the bonus room cold when the rest of the house is fine? It has roughly five exterior surfaces instead of two and usually one duct. The system was never sized for it.
Should we start with the ceiling or the floor? The floor over the garage, almost always. The garage behaves like outdoors and the batt in that floor is usually hanging loose.
It bakes in the afternoon and freezes by morning. Is that normal? On an exposed lot above the valley, yes, and it is mostly air movement rather than conduction. Sealing the knee wall junctions is what settles it.
How much does bonus room spray foam insulation cost in Drumheller? It follows the sprayed area and depth, and a bonus room is a small area, so this is usually one of the less costly items in a house. Access is the variable; a finished ceiling that has to come down adds more than the foam does.
How do I choose a bonus room spray foam contractor in Drumheller? Ask whether the quote includes the floor over the garage and the knee wall junctions, not just the sloped ceiling. A ceiling-only scope is quoting the visible third of the problem.
Check the depth with the R-value calculator, then get a free Drumheller quote. More on Bonus Room Spray Foam Insulation Alberta province-wide.