So, what’s wrong. I think the applicator put the water seal on too thickly, or it did not sink into the wood, or both. The fix: power wash that stuff off and leave the mahogany as is. It resists decay and will weather to a very handsome (in my opinion) silver.
You cannot keep it looking new; Mother Nature is going to change the color of the wood no matter what. There are products that claim to keep the wood new looking, but they have to be applied every year or so and tend to turn the wood yellowish. If you really want to preserve the wood, apply a single thin coat of a semitransparent stain. It will sink into the wood, will not peel, and will last five years. It comes in earth colors.
As for the clear sealers, their manufacturers are laughing all the way to the bank, because such sealers do not last more than a year, two at the most.
One other commonly available wood that resists decay even better than mahogany is pressure-treated wood. It is not the old p-t, which contained the scary words chromated copper arsenate, but one that contains less scary chemicals.
Q.I just put a coat of semitransparent stain on my mahogany deck, then learned that it will rain tomorrow. Anything I can do about that?
AL, from Newton
A. If the deck is not too big, throw a tarp over it. Otherwise, hope that the stain has dried by the time it gets wet.
Q.I have access to a lot of free fiberglass insulation, backed by a paper vapor barrier. I have insulation up to the tops of the floor joists in my attic. Is there any point of no return as to the thickness of insulation in the attic?
ROB AHEARN, Tewksbury
A. Not really. Take off that paper backing, and you can add up to 4 feet, as long as it doesn’t cover the soffits (eaves) or any vents, or block any routes of ventilation. Put the first layer on at right angles to the joists, then alternate the direction with each layer. Wear gloves, eye protection, and a mask when working with fiberglass.
