Peeling Deck Sanded & Restained in Thornhill

This Thornhill backyard deck is a good example of the most common deck staining problem we see across the GTA: a previous stain that peeled. The deck itself was sound. Pressure-treated boards, a privacy screen along one side, picket railings at the end, all structurally fine. But the finish had failed. In the before photo you can see the old coating lifting in sheets, grey bare patches where it had already come off, and darker areas where it was still hanging on. Walking on it in bare feet meant catching flakes of stain.

Why the old deck stain peeled

The previous product was a film-forming stain: it sits on top of the wood like a thin layer of paint. On a horizontal surface like a deck floor, where water sits, sun beats down and people walk, a film like that eventually cracks, lets moisture underneath and lifts. Once it starts peeling, another coat on top only peels with it. The fix is not more stain; it is removing the film completely and switching to a finish that soaks into the wood instead of sitting on it.

Sanding the deck back to bare wood

We sanded the entire deck floor down to clean, bare wood. That means every trace of the old film removed, the grey weathered surface taken off, and the boards brought back to the pale, even colour you see in the during photo. Sanding is the slow part of deck restoration and the part that most often gets skipped in favour of a pressure wash. A pressure wash alone would have left old stain in the grain and tear marks in the soft pressure-treated wood, and the new stain would have gone on patchy. On a deck that has peeled once, sanding is the only way to get an even result.

Oil-based penetrating deck stain

With the boards clean and dry, we applied an oil-based penetrating stain. Unlike the film-forming product that failed, an oil-based stain soaks into the wood fibres and cures inside the board. There is no surface layer to crack or lift, so it does not peel. It wears gradually and evenly instead, and when it is time for a maintenance coat in a few years, the new coat goes straight on after a clean, without stripping. On this deck it brought out the grain of the pressure-treated boards in a warm, rich brown, as you can see in the after photo, with the colour sitting in the wood rather than on it.

The result

A deck that looks new, in the same footprint, with the same boards. No peeling, no flaking underfoot, and a finish chosen to age well through Thornhill winters. The privacy screen and railings were done to match, so the whole deck reads as one colour.

Deck restoration like this, sanding to bare wood and refinishing with a penetrating stain, is the core of our deck, fence and porch staining service across Toronto and the GTA, and it comes with our 3-year non-peeling warranty. If your deck stain is peeling in Thornhill, Richmond Hill, Vaughan, Markham or anywhere in the GTA, we'll look at the wood and give you a written quote. Free on-site estimate.