for Cold Climate Housing and much more

Last Updated: , Created: Saturday, October 6th, 2001

What happens when laminated floorings get wet?

Any wood product will expand when it gets wet, some worse than others. Today we have a wide variety of wood or wood like flooring products.

Massive Hardwood

First you should understand that even massive hardwood, if allowed to stay wet or overly humid for too long will swell up and potentially buckle the entire floor, perhaps never shrinking back to its original size. Even just a little water that gets in the end of a board under the finish will begin to crack the finish as you can see in the first photo.

Laminated Floorings

Laminated floorings come in a wide variety of materials these days. Actually anything that is made of built up layers is considered a laminate, although more and more the industry is beginning to reserve the term laminate for those flooring materials that have a fibreboard base and a photographic plastic finish. In all these cases, if moisture or liquid water is allowed to come into contact with the fibreboard base, it will swell as you can see in the first photo.

When you use these products and there is any chance of moisture coming from below, make sure that you have a moisture proof backing built right into the underside the fibreboard. If there is any chance of spilling from above, such as kitchen or bathroom applications, you must use a continuous bead of waterproof glue along every joint and carefully use silicone caulking around the edge to prevent any spills from reaching the core, or even the tongue and groove.

Real Hardwood Laminations

When the top layer is real hardwood and not a plastic photographic sheet, the base is often plywood. This too is susceptible to swelling if it gets too wet, but it has a far greater tolerance for moisture than the fibreboard core, even a greater tollerance for moisture than massive hardwood.

Basement recommendations

In a basement where moisture problems are probable, I would not use real hardwood because of the buckling potential that could happen simply with summer humidity, and I would not use fibreboard either because of the swelling potential from any minor water problems. The only "hardwood style" floor I would use in a below grade basement application would be a real wood top with a plywood base allowed to float over a plastic cushion base. It is just much more forgiving. You may have trouble finding these "real wood laminate floors" in the renovation centres, but all the better flooring stores carry them.

Non-Glued vinyl

I did quickly mention a new thick vinyl flooring that does not need to be glued down that could well be used in a moist basement situation. It is called PolyStyl, and I am really impressed with it. In fact we will do a whole show segment on it in an upcoming show.


Keywords: Floors, Hardwood, Humidity, Moisture, Vinyl, Kitchen, Waterproof, Renovation, Laminate, Basement, Bathroom, Water, Wood, Problems

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