May 2, 2015 4 min read

Peter Hotton isn’t writing today. Instead we’re publishing letters from his 2003 columns.

Q. My fireplace has glass doors. I would like to change it to a gas log. Is that possible? I was told that I would need an entirely new firebox for about $3,000 to accommodate a gas log. What should I do?

A. That might be required for a gas log exhausting up the chimney, but it may not if you use a gas log with a power exhaust venting through a wall instead of up the chimney. And, instead of a free-standing gas log, use a little stove containing the gas log; such stoves are called gas log fireplaces. That will preclude the need for rebuilding the firebox and you will enjoy the dancing flames anyway. All this is possible and practical if you have gas in the house.

Q. My outside window sills are getting quite spongy from decay. I asked several people what I should do. Some said to cover the sills with aluminum, some said to replace the sills, and some said fill with a filler material. What should I do?

A. I’m with the filler people. Dig out decay with hammer and chisel, reaching bare (sound) wood. Treat the space with bleach, to kill any decay-causing fungi, rinse, and let dry. Then fill with Minwax’s epoxy wood rot filler. It is a two-part system that is tricky to use but works wonders. If the decay goes all the way through the sill, chances are you have to replace the entire sill. If the decay is in the front of the sill, you can saw it off and screw on a filler piece of new wood (pressure-treated).

Covering decay with aluminum guarantees more decay.

Q. I have a piece of 3/4-inch CDX plywood 6 feet long and 15 inches wide. It is bending along its length; if you put it down arch side down, the distance from the top of the arch to the floor is 2 inches. How can I straighten it out? I want to build a long box with that piece and other pieces. If I put a flat piece of plywood down on the driveway in the sun, how will the piece curve?

A. The piece bent because the underside (the concave side of the curve) dried out and contracted. The same thing would happen with the flat piece in the sun; the top would dry out and the curve would be up at each end.

To correct, put the bent piece in the sun, curved side down, put weights on it and see what happens. A better way is to suspend the piece on two 2-by-4s, curved side down, and put weights on the piece until it is slightly bowed the other way. You could wet the underside, which might help.

Q. I plan to put in a sump and a pump in my cellar to protect against flooding. How can I cut through 4 inches of concrete to dig a sump?

A. There are concrete cutters out there who will do the job for $200 and up per cut. To do it yourself, I suggest you rent an impact drill from a rental place. Make sure you get an extra long bit. Then make a series of holes along a line and chip out the remaining concrete.

If you put the sump against a foundation wall, you will have to make three cuts. If you put the sump in a corner, you will need two cuts.

You might be able to rent a rotary saw with an abrasive blade for very slow cutting, but I don’t know how deep such a blade will go.

Wear a mask when cutting concrete; you do not want to breathe concrete dust.