We start this week's column with two questions from homeowners with ice dam problems.
Q. We just had two major snowstorms in early December and now we have ice dams. We waited for the leaves to fall before getting the gutters cleaned for winter, but the snow beat us. Now we have clogged gutters, snow and ice on the roof. I was rudely awakened to water on my head coming in through the window casing and ceiling. It looks like there is ice forming on the ceiling of the attic in eaves area. Water keeps coming in the walls and ceiling and we are not sure how to handle this. Do we call a roofer?
SUE, from Lexington
Q. We had a new roof installed two years ago. The following winter, when we had all the huge snowstorms one after the other, we had a water leak through the walls on one part of the house. I suspect that room isn't insulated, which might explain why the water only came in that area. We just had the major water damage to the walls and ceiling in the room below that was repaired two months ago. Last night, I came home and found water dripping down the wall in that same room. It stopped leaking by the time I went to bed. After almost four years, am I under warranty for that roof? I asked them to install measures to prevent ice dams, but I don't know if it was done. Is the roofer responsible for fixing that or do we just have to get something new installed? Would cutting off heat to that room, and/or ripping out the ceiling and putting in insulation be solutions?
RUTHIE, by e-mail
A. Both of these anguished cries are about ice dams, or rather ice damns, so here is the Handyman's annual treatise on ice dams. Sue's problem is aggravated by overflowing gutters, but the biggest problem is ice dams. Also, the ice on the attic ceiling near the eaves means there is a leak, or water vapor is condensing on the cold ceiling.
Ice dams are caused by warm roofs. They have nothing to do with gutters, although overflowing gutters can cause leaks, particularly on walls under the eaves. In a house with little insulation on the attic floor and no ventilation or inadequate ventilation, the snow on the roof cools off quickly at night, and ice forms under the snow. Then when the warm roof melts the ice, the water is trapped by ice on the edge of the roof (the ice dam), backs up under the shingles and into the house.
Ice dams can be prevented by insulating the attic floor, but a critical part of this project is to keep the insulation out of the eaves, where the roof overhangs the wall. Equally important is to install a vapor barrier under the insulation, and to vent the attic. Standard venting used to be louvers at each gable end, but now proper ventilation is a full-length ridge vent and soffit vents (vents on the underside of the overhang). These soffit vents must be a continuous 2-inch-wide screened strip, not those circular vents spaced every few feet. The insulation and ventilation will keep the attic cold, which in turn keeps the roof cold, and ice dams cannot form on a cold roof.
Incidentally, take a look around the neighborhood after a heavy snow. Most roofs on insulated and ventilated attics will retain the snow. Those with bare roofs are uninsulated and possibly inadequately ventilated.
For caller Sue, the gutters may be overflowing, even when they are not clogged. You can have a gutter man inspect them to make sure the water is dripping in the middle of the gutters. If water drips too close to the back of the gutter, it will overflow the back of the gutter and can percolate into the eaves and walls.
For e-mailer Ruthie, a roof is usually warranted for a year, even though the shingles themselves are warranted for 25 years and longer. For starters, call the roofer and find out if he put an Ice and Water Shield on the edge of the roof, under the shingles. Perhaps you can have a roofer or engineer inspect the roof and other aspects of the house, such as insulation and ventilation.
Another thing to do when snow and ice strike is to scrape the snow off roofs. But this is dangerous and can damage the roof. Still another thing you can do is to have an Ice and Water Shield, a waterproof membrane, installed on the edge of the roof, under the shingles. This can be done only when the shingles are removed. Such a membrane will not prevent ice dams, but will prevent leaks from water backed up by the dam.
Q. My tub surround is tiled up to 18 inches from the ceiling, and papered on the top section. I am getting mold on that paper, but not on the ceiling. How can I prevent that?
JACK, from Halifax
A. Ventilate, ventilate, ventilate. If the ventilation does not reach that surround area, consider putting the exhaust fan (if you have one, and it should be exhausting outdoors) into the surround area. If you do not have one, then install one. You could also extend the tiles to the ceiling, making the wall easier to keep clean. Or, install shiny plastic laminate on the wall areas, to make it resistant to mold and easier to clean.
Q. When I go away for a few weeks this winter, I plan to keep the heat on. Should I shut off the water at the meter? I am concerned about frozen pipes leaking a lot of water in case of a break.
CONCERNED
A. Do not shut off the water; your boiler has an automatic refill valve that will add water when needed. If you shut off the water, the system will shut itself off if it cannot get more water. As for frozen pipes, if you have not had them before, it is unlikely you will have them now, even if you keep the temp at 50 or so. Or, put a freeze alarm on your phone; it will inform you if the temp goes too low.
Q. I had a hot air furnace put in, fired by gas. I closed the vents in two rooms that are not used, to save heating fuel. The man who cleaned my furnace said that air should circulate in those rooms, and suggested I let those rooms heat up. Is that necessary?
TOO DARNED HOT
A. No, it is not necessary. Keep the vents closed. Also, in a modern hot air system, there are dampers on the round ducts leading to all rooms. You can see the damper handle; it if is parallel to the length of the duct, it is open; if it is vertical, it is closed. Those dampers were there to balance the system, allowing the proper amount of air to go onto each room. Completely closed, they will keep the rooms cold, as they should be when they are not used.
Q. Dare I use my unvented gas logs? They are creating a lot of soot, which is very difficult to clean off walls and ceilings. It often smudges when I try to clean it.
A.S., Frankton, Va.
A. Here we go again. Unvented gas logs, unvented fireplaces, unvented stoves. Unvented brains. These devices are equipped with a fail safe feature that turns off the unit when oxygen levels get too low, and I believe are legal in all states, including the extremely cautious Commonwealth of Massachusetts. The burning gas (propane in your case) creates a lot of soot, just as an oily candle does. You might be able to have the flame adjusted to produce less soot. And do not use the device except for supplemental heat.
Your best bet is to stop using this device, and see if you can have it attached to a power vent venting the fumes outdoors. Or, buy a new log or heater that is power vented through a wall. You might be able to clean the soot off with a Mr. Clean Magic Eraser. If that does not work, a strong detergent solution will work, plus lots of elbow grease.
Globe Handyman on Call Peter Hotton is also in the Styles Section on Thursdays. He is available 1-6 p.m. Tuesdays to answer questions on house repair. Call 617-929-2930. Hotton also chats on line about house matters 2-3 p.m. Thursdays. To participate, go to Boston.com Hotton's e-mail is photton@globe.com.
