Which Flooring Expands and Contracts the Least?

While the expansion and contraction of a particular kind of flooring is not usually one of the top 10 factors in the decision about which kind to buy, it is a feature of almost all floors. Changes in humidity and temperature have an effect on most building materials. It’s minimal – we wouldn’t be able to build buildings if steel had a 25% change in size when the weather shifted – but it is still something we have to prepare for.

The changes are minimal, but they matter, and if your room is subject to greater changes it may actually be a big issue for you. Regardless, with most flooring we have to leave ‘expansion gaps’ between the floor and the walls to allow these changes to happen without harming the floor.

Here’s a look at the main types of hard flooring – I’m leaving out carpeting in this piece. My rankings are not based on good chemistry, a Dimensional Change Coefficient for instance. I can only find those for wood, so I’m using recommended expansion gaps. That’s the most across-the-board factor I can find, how much space we are to leave between the edge of the flooring and the walls or other vertical surfaces, though there are ranges within each.

So which are the best, ‘best’ in our case meaning they change the least? We’ll go best to worst. I’ll list the ranges of expansion gaps I could find, but keep in mind that whatever floor you buy, your instructions will give you your exact number.

Top Choice

Loose Lay Vinyl Planks

These are designed to not react at all to standard indoor environmental changes. In fact, the installation relies on that. These are placed snug against each other, and snug against the walls. That’s what keeps them in place.

This is a new-ish product (just a couple of years old at the time of writing) in part because its complete dimensional stability has been so unattainable. Even other vinyl planks, the click-together kinds, which rank very high here, aren’t 100%.