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Moisture from gas heaters creates mold

I own a house that I use as a vacation house six weeks a year. When I went there in November and had the gas turned on, my floor furnace was tagged as unsafe. The gas company recommended infrared gas heaters. The heaters did a good job in heating, but the moisture was unbelievable. The gas company did not mention a word about the moisture or sweating on the walls. I returned in January to find mold on lower walls and windows sills. The heaters are ventless. Do you have a solution?

J.G., by e-mail

Sure do. Get rid of those useless ventless heaters. They are dangerous, even though they have a safeguard that shuts them off when oxygen levels get too low in the house. They may be illegal in many states, and should be illegal in every state, in my opinion. It may be that the gas company did not tell you about the moisture because it sells gas and little else. It also did not tell you that burning gas produces 2 cubic feet of water vapor for 1 cubic foot of gas burned. That is a lot of water vapor, and it is condensing on walls and causing mold.

Have that floor furnace fixed so that it exhausts through a chimney or power vent, and is safe. Or install a gas stove or fireplace with a power vent through a wall. You should get your money back for those infrared heaters, and the gas company should pay for de-molding your house. Fat chance, perhaps, but it is worth mentioning.

Does it make sense to remove gutters with recurring ice dams, especially if rain water is likely to drain away from the house?

B.J., by e-mail

I am beginning to think that gutters are indeed part of the problem with ice dams. They don't necessarily cause dams themselves and subsequent leaks, but when they freeze up, water can percolate under the eave and leak into the walls and/or cascade down the walls, forming huge icicles and sheets of ice. It does make sense to take down gutters, as long as there is a roof overhang of at least 6 inches. And if the land slopes down from the house, all the better. You could build a concrete apron around the house to keep water from eroding that sloping land.

I have a very nice painted wood front door that I cannot close because of leaks near the top of the door from ice and snow. Things have improved a little; now I must push it to catch. What can I do to prevent this from happening again?



The leaks caused the door to expand. You have to wait until the door dries out and shrinks, making it latchable again. Wait as long as practicable, perhaps until around June 1, before it starts to get humid outdoors. When the door is totally dry, scrape off any peeling paint from the edges, then prime all edges -- top, sides, and bottom -- with an oil-based exterior primer and finish with latex house paint or a latex enamel. Of course, repaint the face of the door if the paint is in bad shape. A good primer and finish paint will help keep moisutre out of the door, preventing the dreaded swelling. You may have to take the door off the hinges in order to prime and paint the bottom edge; do not neglect it.

I have an oil-fired boiler in the middle of my house, and the tank is also inside. I need more room. Can I put a new boiler with power vent in the garage? Can I also put the oil tank in the garage? I don't need the garage for my cars.

FRANK, Rockport

I think it is possible, because I have seen tanks and boilers in garages. Check with your building inspector and/or fire marshal first. You could also put both units in an attached out-building as long as the tank and boiler are the proper distance apart. You mentioned a new tank, which is tall and slim and which holds as much as standard tanks but takes up less room. That would be a great idea, with the added bonus that you don't have to worry about oil leaks from the tank for a long time.

I am thinking of insulating the ceiling of my cellar to help keep the kitchen floor warm. One book on insulation said yes, another said no; why block off heat from the furnace in the cellar? I have insulated the perimeter of the basement wall, just above the foundation. Who is right? Can I insulate just under the kitchen?

H.F., Norwood

The book that says do not must be ancient, especially in its claim that heat from the furnace (or boiler) will help heat the house. Do insulate the entire cellar ceiling. Insulating a part of the ceiling will do little good. The heat in the basement will do no good if the cellar temp is lower than that upstairs. How about the fact that warm air rises? Yes, that is a fact, but heat loss through an uninsulated wall, ceiling, or floor will move in all directions: sideways (through a wall), up (through a ceiling), or down (through a floor).

Since Christmas, I have an odor in my apartment that is coming from the baseboard heaters, where the copper heating pipe comes up through the floor. It smells of potpourri and mothballs. How can I stop that smell?


Sounds as if one of your neighbors took his Santa suit out of storage for the holiday. Odors will find their way through the smallest openings. I suggest you caulk the pipe where it comes up through the floor, and any other pipes you see coming up through the floor. Use caulk or Mortite, a soft, rope-like weatherstripping. Put a plastic ring on the floor around the pipe, one that is designed to complete the installation of such pipes.

I tried and tried to shut off the valve leading to my toilet tank, without success. Can I use a bit of WD-40 to loosen it?

FRUSTRATEDPatience will help, and WD-40 may do the trick. When a valve like that freezes (it is attached to a rather weak, often flexible pipe), be careful that you don't bend the pipe. Also, wear a heavy canvas glove to give you a better grip, or use one of those rubber mats that you can wrap the handle with, also to give a better grip. If all fails, have a plumber try his luck. If he breaks the pipe, he can fix it.

I would like to refinish my kitchen sink, which is cast iron set in a countertop. I was told that reglazers will do tubs, but not kitchen sinks. Are there do-it-yourself kits available?

EAGER, in San Jose, Calif.

I think a reglazed sink (usually an epoxy finish) will not stand up well to the wear and tear that a kitchen sink must take. Do-it-yourself kits are iffy, so I suggest you go for a new sink and be done with it. Maybe a stainless-steel one.

My windows are double-paned with aluminum frames. Water condenses on the frames but not on the glass. How can I prevent that?

NANCY BROWN, Gadsden, Ala.

For starters, reduce the moisture in the house, which is easier said than done. But here's a trick that might work. If you can get it in the South, buy self-adhesive foam strips of weatherstripping, and apply them to the frames. They will keep the moisture (water vapor) away from the cold aluminum. If you cannot find the weatherstripping or something similar, glue wood strips to the frame, and paint or stain and varnish them. They will not only keep water vapor away from the aluminum, but also they will look a sight better.

Globe Handyman on Call Peter Hotton is available 1-6 p.m. Tuesdays to answer questions on house repair. Call 617-929-2930. Hotton also chats online about house matters 2-3 p.m. Thursdays. To participate, go to Hotton's e-mail is

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