Question: The composite decking at my house has been scratched and grooved over time. Can it be sanded and then stained? --Washington
Answer: You may be able to smooth over the scratches, but you could change the surface texture and wind up with a deck that looks worse than it does now. So proceed cautiously.
If you know the manufacturer, contact its technical services department for advice. It's worth checking because composite decking is a term that's sometimes used to describe products made entirely of plastic, as well as wood-plastic composites that are the same material all the way through and wood-plastic cores surrounded by a plastic shell. A single manufacturer may offer several types, each of which requires a different scratch-removal strategy.
For example, TimberTech (800-307-7780, www.timbertech.com ) recommends using a wire brush to smooth over scratches in its wood-plastic composites (TwinFinish, ReliaBoard, DockSider and certain colors of Floorizon).
But to treat its all-plastic Earthwood decking or darker colors of Floorizon, the company suggests using a round-tip soldering iron to melt scratches so they blend in, or dabbing on specific wood stains. Care recommendations for Floorizon vary by color because the darker tints are mostly near the surface. There is no recommended way to deal with scratches in TimberTech's Earthwood Evolutions, a wood-plastic composite wrapped in a poly shell.
Some manufacturers make wood-plastic composite decking with a surface molded to simulate the grain pattern in natural wood. Although it's possible to sand or wire-brush these products, doing so removes the grain pattern. So unless you completely resurface the deck, your efforts to eradicate scratches will just make the damaged areas bigger.
If you do attempt a spot treatment, it may take two months or a little longer for the color to even out through natural weathering.
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