Those gaps opening up between your floorboards are almost certainly normal. Every October, when Okanagan furnaces switch on and indoor air dries out, hardwood boards give up moisture and shrink across their width. Thin gaps appear. Come spring, when humidity climbs back, they close again. It is seasonal movement, not a defect.
We get these calls every fall from Kelowna homeowners who are convinced their floor is failing. Almost always, it is not. But knowing which gaps are normal and which ones are telling you something is genuinely useful — so here is how to read your floor.
Why Does the Okanagan Climate Affect Hardwood Floors So Much?
Wood is hygroscopic. That is the technical way of saying it constantly exchanges moisture with the air around it — absorbing when the air is damp, releasing when the air is dry, and changing dimension as it does.
The Okanagan gives that process a real workout. We live in a semi-arid region with cold, dry winters, and then we heat our homes with forced air for five or six months straight. Furnace heat strips whatever humidity was left in the indoor air. It is not unusual for indoor relative humidity in a Kelowna home to sit in the teens through January — well below what wood flooring is designed for.
Here is the part that surprises people: boards shrink across their width, not their length. So a floor with wide planks shows more visible gapping than a floor with narrow strips, simply because there is more shrinkage happening per board. Nothing is wrong with the wide-plank floor. There is just more movement to see.
Species matters too. Some hardwoods move more than others, and wide-plank oak behaves differently from narrow maple strip. Our hardwood flooring winter guide breaks down which species are most prone to gapping, and our post on identifying wood covers how to tell what you have.
What Humidity Level Do Hardwood Floors Actually Need?
The National Wood Flooring Association recommends holding indoor relative humidity between 30% and 50% year-round. That range keeps wood at roughly 6–9% moisture content, which is the sweet spot solid hardwood is milled and installed for.
| Indoor relative humidity | What happens to your floor | What to do |
|---|---|---|
| Below 30% | Boards shrink. Gaps open between planks. Squeaks develop. In extreme dryness, surface checking (fine splits along the grain). | Add humidity — humidifier, and check your hygrometer daily |
| 30–50% | Stable. Minimal movement. This is the target. | Maintain it |
| Above 60% | Boards absorb moisture and swell. Edges lift — this is cupping. In severe cases, boards crown or buckle. | Dehumidify, and find the moisture source |
Buy a hygrometer. They cost about fifteen dollars, and it is the single most useful thing you can do for a hardwood floor. Put one on the main floor, away from vents and exterior doors. Without one you are guessing — and most people guess high.
Worth knowing: humidity and relative humidity are not the same thing, and the difference matters when you are reading that gauge. We covered it properly in our hardwood flooring winter guide, along with the ideal temperature range to pair with it.
Which Winter Gaps Are Normal and Which Mean Trouble?
This is the part worth bookmarking.
Normal seasonal gapping looks like:
- Thin and even — roughly the width of a dime edge or less
- Consistent across the whole floor, not concentrated in one area
- Appearing in late autumn and closing again by late spring
- No change in how the floor feels underfoot
Worth having assessed:
- Gaps wide enough to swallow a coin that do not close in spring
- Uneven gapping — several tight boards, then one large gap. This can indicate boards that have separated as a group, sometimes from an installation or fastening issue
- Gaps with cupping alongside them — edges higher than the centre of the board points to a moisture problem, not a dryness problem, and those two need opposite responses
- Gapping concentrated near a dishwasher, fridge line, exterior door, or bathroom — that is a localised moisture pattern, and it usually means a leak
- Finish cracking or flaking along the gap edges — the finish film has been stretched past what it can handle
The one that genuinely warrants a phone call is cupping. Dry-air gapping is a nuisance that reverses itself. Cupping means water is getting somewhere it should not, and the longer it goes the more likely you are looking at board replacement rather than a refinish.
How Do You Prevent Winter Gaps in Hardwood Floors?
You cannot eliminate seasonal movement — wood is going to be wood. But you can keep it in a range where you barely notice it.
- Run a humidifier from October through April. A whole-home unit on the furnace is the best solution. Portable units work for individual rooms but need refilling more often than most people expect.
- Watch a hygrometer, not the weather. Target 30–50%. Adjust as you go.
- Keep the thermostat steady. Wild temperature swings drive humidity swings. Consistency is easier on the floor than a warm-cold-warm cycle.
- Do not aim heat vents at the floor. Deflectors are a couple of dollars and they stop you from creating a bone-dry microclimate in one spot.
- Put mats at every entry. Okanagan winters mean snow, slush, and road salt. Salt is genuinely damaging to a finish — it is abrasive and it holds moisture against the wood.
- Wipe up immediately. Melting snow off boots is the most common source of winter water damage we see.
- Never wet-mop. Use a barely damp microfibre mop and a cleaner made for hardwood. Our full routine is in our guide to cleaning your hardwood.
- Add area rugs in the highest-traffic paths. Front door to kitchen, kitchen to living room. Just remember to keep a felt pad underneath rather than rubber backing, which traps moisture.
- Do not fill seasonal gaps. Wood filler in a gap that is going to close in April will be pushed out — or worse, will force the boards apart. Filler belongs in a full refinish, applied by someone who knows which gaps are permanent.
That last one comes up constantly. Every fall someone asks about caulking the gaps. Please do not.
When Do Gaps Mean It Is Time to Refinish?
Sometimes the gaps are not the problem — they are the messenger.
If your floor has reached the point where gaps stay open through summer, where the finish is worn thin along the board edges, or where years of seasonal movement have left the surface looking tired regardless of the season, a full refinish is what resets it. Sanding to bare wood, filling the gaps that are genuinely permanent, and laying down fresh coats gives you another decade or two out of a floor you already own.
The right time to do it, incidentally, is not mid-winter. A floor that is at its driest and most contracted is not in an ideal state for filling and finishing. Late spring through early fall, when the boards have settled back, gives a better result — which is worth knowing now if you are planning ahead.
Not sure whether your floor needs a full refinish or just a re-coat? Our guide to full refinish vs. buff and re-coat walks through the difference, and our Kelowna refinishing cost guide covers what each one runs.
Get an Honest Assessment
Worried about what your floor is doing this winter? Send us a photo, or book a free assessment and we will take a look. If it is normal seasonal movement, we will tell you that and you can stop worrying about it — no charge, no sales pitch.
Strong Roots Flooring
2545 Enterprise Way, Units 109–110, Kelowna, BC
250-765-3123
[email protected]
Family-owned and refinishing floors in the Okanagan since 2006. We serve Kelowna, West Kelowna, Lake Country, Peachland, Summerland, Penticton, and occasionally clients throughout British Columbia.