Ask the Carpenter: How to get rid of those white deck stains

Ask the Expert Home Improvement
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Q. We have a mahogany front deck that’s two years old and has white smudgy areas on it. We used calcium chloride on slippery parts of it this winter. Also, the concrete stairs and brick walkway leading up to the deck were treated with calcium chloride, too, so some of that was tracked onto the deck as folks entered the house. How do we remove the white spotty areas before we re-treat our deck? Any suggestions for how to avoid this happening again next winter? Should we cover the deck with something?

S & L, Andover

A. Those white spots are from the ice melt. I’m hoping that you can simply wash out those stains. If not, give your deck a light sanding and reapply the finish. I don’t put a cover on my deck. The best you can do is shovel to keep up with the ice and use ice melt.


Q. I have a two-story Colonial with an attached garage. The shingles and the sheathing on the front (the north side) were replaced four years ago. This fall I noticed a ceiling stain where the house attaches to the garage. Our roofer sent someone to check the leak, and that person said nails had popped on the wooden clapboards. He suggested vinyl siding. Have you heard of this? Who can I contact to get an independent opinion of what is causing the leak? Could this leak be the cause of the excessive moisture in the attic?


A. It’s hard for me to tell without seeing the staining, but I’d guess that when they repaired the sidewall/siding they missed something. Popped nails should not cause ceiling staining. I would ask a qualified carpenter in your area with a reputation as being a good problem solver to evaluate it.


Q. I have a home that was built in 1920 in Jamaica Plain. It was rehabilitated in 1996, and the living room was built over the garage. The living room is freezing during the winter because the garage is not heated in any way. I had someone check the insulation, but I’m wondering whether there’s anything else I can do. I use space heaters, but the cost is getting really expensive. I would really appreciate any advice you have to offer.


A. It sounds like there’s a problem with your insulation. You could try insulating the garage walls. Also, does your living room have carpet? That can also keep out some of the cold. Having well-insulated garage doors also helps. If all else fails, you can add heat, which can be costly.



Dear Rob

Reader weighs in on the April 1 column about a vent that is damaging a home
The problem is not the paint or the clapboards; it is the installation of the flue gas termination. The discharge is supposed to be facing straight out 1 foot above the intake, and the intake should be 18 inches above anticipated snow levels. Right now the flue gas is being discharged sideways across the house. The flue gases, which are highly acidic, are eating away at the paint.

PHILIP POLCARO, Metropolitan Air-Conditioning and Heating

Rob: Thank you for your help, Philip.

Rob Robillard is a general contractor, carpenter, editor of, and principal of a carpentry and renovation business. Send your questions to or tweet them to @robertrobillard. Subscribe to our free real estate newsletter at