In Edmonton, Your Attic’s R-Value Is Really Its Birth Year
Nowhere else in the region holds this range. Edmonton has attics closed up in 1948 and attics closed up last spring, and the gap between what they hold is bigger than most homeowners imagine.
The mature core: built before insulation was a number anyone argued about
Highlands, Ritchie, Westmount, Glenora and Bonnie Doon went up when an insulated ceiling meant a few inches of whatever was available, and where those attics have been improved at all it was usually a single top-up sometime in the 1980s. Measured today they commonly land near R‑20 — roughly a third of what the same house would be built to now. These are also the attics where we most often find old wiring running through the joist bays, which is a reason to look before anything gets blown, not after.
Mill Woods and the seventies belt: one enormous cohort, all due together
The single largest block of same-era attics in the province sits in Mill Woods and its contemporaries. They were built to a real standard — typically blown to something like R‑40 — and that is exactly the trap. An attic blown to R‑40 in the seventies has had fifty years to settle and wind-wash, and it very often measures closer to R‑25 today. The label on the paperwork and the ruler in the insulation tell two different stories.
The west end and the nineties: close, but a generation behind
Callingwood, Lewis Estates, Rosenthal, Secord and The Uplands were built to a standard most owners assume is current. It isn’t — it’s one code cycle back, and settling has taken a few inches off since. These attics rarely need emptying; they need the depth they were nearly given.
The new southeast: at code, and worth leaving alone
Laurel, Tamarack, Summerside, McConachie and Keswick were built to the current effective‑R requirement and, in most cases, do not need us. What those tight, well-sealed homes are prone to instead is moisture — warm household air finding its way into a cold attic and freezing on the sheathing, then melting out in spring. If that’s what’s happening in yours, more insulation on top is the wrong answer, and our guide to attic rain in Edmonton homes explains the right one.
Which Edmonton homes this is actually for
Anything closed up before about 2005, and especially the seventies belt where the original number was decent and the settled number isn’t. Post-2010 builds in the southeast usually need nothing from us — we’ll measure yours for free and say so.
