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TOPIC: Screws

Log cabin with vaulted ceiling

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We are contemplating installing a metal roof over existing shingle on a northwoods log cabin (whole logs) with a vaulted ceiling and no attic. This is not a year-round cabin; there's no insulation. Our concerns are: Noise of rain and falling pine cones, and the occasional scrambling squirrel; and whether or not the metal roof, possibly in forest green color, will turn the cabin into a sauna on sunny summer days. The cabin is on an island in a northwoods lake, and reroofing is a major pain; thus the ability to get a long-lasting metal roof and avoid a tear-off is very appealing. Are our concerns well-found or baseless?
Guest User

12/26/2001
A little more information on the ceiling/roof assembly would be helpful however I will assume you have a solid wood deck. The answers to most of your questions are dependant upon the type of metal system you chose. If you applied a vertical rib panel direct to the deck the noise transferance will be less however the heat transferance would be higher which could increase the interior temperature in the summer. Appreciate that the colour of your roof no matter what the material dictates how much of the suns rays are reflected or absorbed. Most of the metal roof systems can be mounted on strapping up off the deck whick will create an air chamber that if vented will eliminate the heat transferance. In most cases you would find your cottage more comfortable in the summer than now. The noise transferance could be higher depending on the profile of the metal roof. Some that are made to lokk like a wood shake have many ribs in them that strengthed the panel and reduce the drumming noise. Additionally some manufacturers offer panels with a granular finish that substantially reduces the noise from rain. Given that you are in the north and receive a substantial amount of snow I would recommend a smooth finish panel to shed the snow. Second I would suggest that you consider a reflective insulation underlayment over your existing roof. There are some that provide up to an R11 on reflecting the heat out and are only 1/4" thick. Finally I would suggest that you strap the roof to keep the metal panels up off the deck and ventilate the chamber. (The new IBC building code calls for 1 1/2" of air space on a cathedral type roof assembly like yours). Good Luck.
Allan Reid
Dura-Loc Roofing Systems, Inc.

12/27/2001
I agree with Al's answer wholeheartedly. Although I know that it might involve expense you'd hoped to avoid, I really suggest creating the vented airspace over the existing roof. Regardless of what roof you install (metal or otherwise), this sort of airspace is wise from a construction standpoint and, as Al points out, it is now required by code. The airspace will help keep the cabin cooler in summer, help to avoid ice or snow damming in the winter, help to minimize noise transfer, and it will help to avoid problems with excessive moisture inside the cabin. Once you choose a metal roof style, the manufacturer, I am sure, will be glad to provide additional assistance and details.
Todd Miller
Isaiah Industries, Inc.

12/27/2001
I built a large (>3000 sq Ft) log cabin in Vermont. I used metal roofing. 12/12 pitch. Single length sheets. Standing seam. Matching (color) screws. Valted ceiling. 2x10 rafters. 10" High density fiberglass insulation. 1x6 T&G interior surface. 5/8" plywood > 30# felt > Metal No strapping. Here's what I know: You can hear a slight metalic sound from outside the house if the roof is struck by an acorn or the like. If you want a loud metal sound when the roof is struck (by rain, acorns, meteorites or other) then mount the metal using strapping. I mounted my metal on 30# felt, flat on 5/8" ply decking. Squirrels do not like metal roofs. They are very slippery. Maybe Vermont has sissy squirrels. The roof (at 12/12) pitch will not allow more then 1/2 to 1 inch of snow to accumulate before it slides off. Rain sounds beautiful, but not due to the metal roof due to vaulted ceiling. If you don't believe me go into the attic of a convention ceiling home (Flat ceiling and asphalt shingles) during a rainstorm. I'm not a professional roofer but I know I would remove the asphalt shingles BEFORE I put down metal, for the same reason I would prepare a smooth flat surface for a new vinyl floor covering. Metal roofing is beautiful and lasts a very long time. Good Luck.
Guest User

1/24/2002
Guest User

1/24/2002
Guest User

1/24/2002
Metal roofing can reflect as much as 70% of the sun's energy. This minimizes the heat retention and as a result less heat is transferred into the building. Research conducted by the Florida Solar Energy Center in 1985 showed that metal experienced as much as 34% less heat gain than asphalt shingles. Results indicated that metal roofing offers a similar effect as R-11 insulation during sunny day conditions.
Guest User

9/22/2002