Flooring in Carstairs, Alberta

The dry season problem

Indoor air here spends the winter below the band wood likes

Southern Alberta sits in the chinook belt, and heated indoor air through the winter routinely falls well under 30 per cent relative humidity. That is below Health Canada’s winter guidance of roughly 30 to 35 per cent, and well below the 35 to 55 per cent band the National Wood Flooring Association associates with dimensional stability in wood. Boards give up moisture, shrink across their width and open small gaps at the joints. In most houses those gaps close again over the summer. The floor is not failing, it is doing what wood does in dry air.

Ask about a wood floor

Flooring Experts Calgary provides flooring installation and repair to homeowners and businesses across Carstairs, Alberta.

Why a floor gaps in February and closes again in July

Carstairs sits on the prairie north of Calgary, in the part of the province where a chinook can move the temperature more than twenty degrees in a matter of hours and the furnace runs hard the rest of the time. The result indoors is air that is genuinely dry. Through the heating season, relative humidity in a heated house here routinely falls well under 30 per cent, below Health Canada's winter guidance of roughly 30 to 35 per cent and a long way below the 35 to 55 per cent band the National Wood Flooring Association ties to dimensional stability in wood.

Wood responds by giving up moisture and shrinking across the width of each board. Joints open slightly. On a wide plank the same percentage of shrinkage shows up as a wider gap, which is why the widest floors always look worst in midwinter. Most of it reverses. By July the boards have taken moisture back on and the gaps have closed to something you stop noticing.

We say this at the quoting stage rather than afterwards, because a homeowner who has not been told will reasonably assume the installation failed.

Deciding width and construction before the order goes in

Almost everything that determines how a wood floor behaves in this climate is settled at selection, not on site.

Board width is the single biggest factor. Narrow boards move the same amount proportionally and far less visibly. Engineered construction, where a wear layer sits over a cross-laminated core, moves less across its width than solid wood of the same size, and that is what makes a wide plank workable in a dry house.

Species and finish matter as well, though less than most people expect. So does what the house does about humidity. A furnace humidifier that is genuinely set and maintained through the heating season keeps the boards closer to the range the manufacturer wrote its instructions around. It does not remove seasonal movement, and no floor should be sold on the promise that it will.

What acclimation is for, and what it is not

Leaving boxes in a room for a fixed number of days is not acclimation. The point is to bring the flooring and the subfloor to a similar moisture content, in the conditions that room will actually hold once people are living in it.

That means the heat on, the house at ordinary humidity, and a meter used on both the material and the subfloor. It also means the flooring is not waiting in an unheated shop or a garage in the meantime, because the moisture content it reaches out there has nothing to do with the room it is going into.

Where a house is new, or has just been through drywall and paint, the building itself is still giving off moisture and the schedule has to account for that too. It is a short conversation at the start of a job and it prevents the long one later.