The previous owner put shingles over the old clapboards, which are nailed on open studs. I plan to remove the shingles. Can I put new clapboards over the old ones? Allen Dakers, Middleborough, Mass.
Answer - Generally it is not recommended because it is difficult to get the clapboards to lie flat and to avoid excessive gaps; the difficulty is increased when nails are driven over gaps, possibly bending or splitting the clapboard. It is difficult because the clapboard spacing (the exposure, that is, of the clapboards, usually 4 inches) is the same for the new clapboards as for the old. Putting shingles over clapboards is easier because the height of the shingles spans several clapboards, about four of them. But you certainly can try. Maybe you will find a technique that works.
An alternative is to put the new clapboards over the old shingles, being sure to drive the new nails into the studs because old shingles and clapboards are not thick enough to hold nails well. This will bring out the wall a little, which will require putting molding around the window and door frames so the new clapboards will have something to butt up against.
Another alternative is to take off both shingles and clapboards and put up plywood or board sheathing, then the new clapboards. This may be difficult because sheathing normally goes under window and door fames. But if you can surmount that problem, you could blow in or install insulation in the wall space after everything is removed.
Still another alternative I am reluctant to suggest because it's costly using twice as many clapboards as normal. And that is to trim a clapboard to four inches, cutting off the thin edge, and inserting it, upside down, against an in-place clapboard. When all the clapboards are inserted like this, you have a flat, even surface that new clapboards can go on nicely.
Question - I took up some wall-to-wall carpeting and plan to put down hardwood over particleboard that is on top of a plywood subfloor. The hardwood manufacturer said to take up the particleboard. Do I really have to? Tom Truax, Acton, Mass.
Answer - Particleboard is a no-no whether you apply the hardwood with adhesive or nail it down. The adhesive might not stick to the particleboard, and nails will not hold in it. Besides, it probably is emitting formaldehyde. You could put a thin layer of plywood over the particleboard, but it would be far better to dump it. Then you can nail the hardwood directly on the plywood, at right angles to the joists. Even plywood will not hold nails very well, so make sure you drive nails through the plywood and into the joists. A cut nail or spiral nail will do nicely, but make sure it is long enough to go through the plywood and at least an inch into the joists. A two-inch nail will be fine.
Question - There are two layers of sheet vinyl on my kitchen floor, and I plan to install 12-by-12-inch squares. The sheet vinyl is in good shape but embossed. Can I put on those tiles? Irving Sall, Norwood, Mass.
Answer - Yes, you can. Get the floor antiseptically clean, and use the peel-and-stick tiles. However, there might be a problem with those embossings, which could ghost through the new tile. To avoid this, maybe, choose a busy pattern for the new tile. The embossing will still ghost through, but you may not see it through that busy pattern.
Question - I would like to keep my polyurethane hardwood floors as shiny as they were originally. How can I do that? They have dulled down considerably, but are in good shape. Julie Santos, Peabody, Mass.
Answer - Even high-gloss polyurethane will dull down in a matter of months. It's the nature of the beast and cannot be helped. Live with them. You might be able to jazz them up a little by light buffing with a dry cloth. Avoid polishes, waxes and the like; they could dull the surface even further. And especially avoid using a silicone-based polish; some silicones can turn the floor into a slippery, slidy skating rink.
Clarification - Oops! Well, not exactly an "oops," but the handyman put in a misleading way to kill and get rid of poison ivy. In an answer to Frank O'Loughlin of Norwell, one of the ways is to use a flamethrower (a weed killer) to kill the ivy and make it easier to remove.
Burning poison ivy is a no-no, said Chris Coakley of Wilmington and Jeff Ayers of South Weymouth. Do not burn poison ivy, they said, because the smoke is toxic and can really do a job on eyes and lungs.
Good point, gentlemen, and appreciated, but the handyman did not suggest burning the entire plant, only burning the roots at ground level, which is enough to kill the plant. Even smoke from burning roots is toxic, but it is certainly less so than burning the entire plant.
So, as with all procedures and treatments of poision ivy, caution and moderation are the better parts of success.
Globe Handyman on Call Peter Hotton will answer reader questions. Write him at the Boston Globe, Boston, MA 02107. The Handyman chats on line Thursdays, 1-2 p.m, at (http://www.boston.com). Keyword: Chat.