Handyman on Call

Insulating basement ceiling is not a futile effort

August 21, 2011

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I wonder if ceiling insulation in a basement does any good. The basement is not heated and gets chilly in winter. The ceiling is insulated with 9 inches of fiberglass batting that was once covered with sheetrock or some other material. The insulation is coming down in places. Will the first floor be warmer if I put in new insulation and replace the ceiling?

CHRISTINE, by e-mail

Oh, yes, insulating the basement ceiling will save heating fuel. People often think basement ceiling insulation is not necessary because warm air rises. That is so, but warm air will be lost in any direction through an uninsulated barrier. If some of the insulation is intact, leave it in place unless it is moldy. Treat any remaining mold with a bleach and water solution, then install 6-inch fiberglass, with the paper vapor barrier up, touching the ceiling above. Staple Tyvek on the bottom of the joists, to keep the insulation in place and to provide extra light. There is no need for any other ceiling material.

When you insulate the ceiling, you can open windows and vents for cross-ventilation, and keep them open all year. The vents will keep the basement dry. The basement, like the attic, is supposed to be cold.

I rebuilt my house from the studs up after Hurricane Katrina. We had all new central air put in. The problem is that some air-conditioning vents sweat. We have had the a/c people check it out and their conclusion is that the attic is too cool. Some engineers I know say that is not correct. When we had the roof replaced, the roofer talked us in to putting in wind-rotating fans to cool the attic. I thought a cool attic helped cool the house. The sweating vents have caused mildew. What is the real cause?

JERRY, of New Orleans

Because the a/c ducts are in the attic, that is the reason they are sweating; water vapor condenses on the cool, uninsulated ducts. Insulate them with duct insulation, 1- or 2-inch fiberglass with a vinyl backing. The fans are doing their job.

I have been thinking about converting my oil burner to gas. I have gas in the house. My oil tank has a hole. I have one quote for a gas insert of about $2,500, including stainless steel liner. To remove and replace the oil tank is $1,500 to $2,000.


That is a no-brainer. You have an ideal situation for converting to gas. Do it immediately, before the snow flies.

How can I fill small holes (up to 3 inches in diameter) in my concrete foundation? Filling them is mainly to keep critters out.


Fill the big holes with concrete. Fasten a piece of plywood on one side of the hole, and then press in concrete very compactly. Buy Concrete Mix in hardware and big-box stores. Just add water. The reason for the plywood is to keep you from pushing the concrete clear through the wall. Anything not heavily compacted will fail, either through a short time or the work of critters. For smaller round holes, drive in a hardwood dowel very tight in the hole. Then cut off each end flush with the concrete. Make sure that dowel is as dry as possible, so it will not shrink in the hole.

I painted my outdoor porch trim with interior paint. Now what can I do?


It may not be the disaster you think. Whatever you put on may have acted as a primer, so repaint with a solid color latex stain or an exterior latex paint. No guarantees, but if the interior paint is well covered, it should work.

I have to replace my concrete landing and steps that were precast and installed many years ago. They look a bit tired and beat up now, but are not seriously out of position. Someone suggested I replace it with a similar precast landing and steps. Would that work?

PATRICIA, of Norwood

It sure would. You can buy a matching precast unit that can be installed after the old one is removed. Because the old one stood for many years without moving or heaving in winter, it was put on a proper foundation. Your new precast can go on that foundation and will last for decades.

I have a cesspool (not a septic tank) that has to be pumped every six months. The pool has a layer of sludge that is so thick there is little room for the normal stuff that goes in the pool. It is also so hard that it is hard to dig out. Is there a good solution to soften the sludge?

TOM, from Falmouth

Water will soften the sludge. The fellow who is pumping out the pool is doing you no favors. My septic cleaner used to pump my pool when I had one, and he always dissolved the sludge with water. Your man should do the same, even if it costs more. If he won’t, find someone who will. Or, install a new septic tank. It will cost maybe $5,000, but it won’t need pumping any more often than every two years or so.

Hotton is also in the g section on Thursdays. He is available 1-6 p.m. Tuesdays to answer questions . Call 617-929-2930. He ( also chats online 2-3 p.m. Thursdays. To participate, go to

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