Hi,
I have a cottage from around 1850 with a leaking roof. The roof was redone about 10 years ago with concrete tiles. The problem is the underlay. As far as I can see, economy model roofing felt (YAM2000) is laid directly on the wood shingles. The wood shingles have chafed holes everywhere in that felt.
The question is what should I do? Since it's important that it goes fast, my thoughts are on the new diffusion-open underlays designed for direct mounting on the rafters. They should withstand the mechanical wear that they may be subjected to.
I have done two roofs before, and installing roof boards is out of the question due to the time it takes. Has anyone tested any of these "modern" products? Would it work to put oil-hardened masonite and then underlay... ideas and experiences are gratefully received.
Andreas
I have a cottage from around 1850 with a leaking roof. The roof was redone about 10 years ago with concrete tiles. The problem is the underlay. As far as I can see, economy model roofing felt (YAM2000) is laid directly on the wood shingles. The wood shingles have chafed holes everywhere in that felt.
The question is what should I do? Since it's important that it goes fast, my thoughts are on the new diffusion-open underlays designed for direct mounting on the rafters. They should withstand the mechanical wear that they may be subjected to.
I have done two roofs before, and installing roof boards is out of the question due to the time it takes. Has anyone tested any of these "modern" products? Would it work to put oil-hardened masonite and then underlay... ideas and experiences are gratefully received.
Andreas
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Hello,
you can nail, for example, 1x5" along the rafters and then nail masonite to them with approximately a 10 cm overlap. That way, the masonite will "hang" a bit, and you can nail battens and lay tiles. I would do the "new" sub-roofs the same way so that they don’t lie directly on the shingles. // Micke
you can nail, for example, 1x5" along the rafters and then nail masonite to them with approximately a 10 cm overlap. That way, the masonite will "hang" a bit, and you can nail battens and lay tiles. I would do the "new" sub-roofs the same way so that they don’t lie directly on the shingles. // Micke
It is quite common to lay oil-hardened masonite on wood shavings roofs, so it should work.
Hello again,
when you normally use oil-tempered hardboard, you have nothing but insulation, air gap, hardboard and then battens with an outer roof, often concrete tiles. But... if you have wood shingles, you can keep the shingles and place the hardboard directly on them or as I described with battens underneath to allow air between the shingles and the hardboard. Any water that may get in under the tiles, whether clay or concrete, should find its way down onto the hardboard and out from the roof or evaporate. Normally, a 45-degree pitch is used to utilize hardboard, but down to about 30 should work. You mention relatively low pitch, which probably means you will remove the shingles and install boards and felt, or remove the shingles and set up a "new sub-roof" directly on the trusses. I don't think tile manufacturers recommend their tiles for very low pitches. Perhaps you could use metal instead for the extension? // Micke
when you normally use oil-tempered hardboard, you have nothing but insulation, air gap, hardboard and then battens with an outer roof, often concrete tiles. But... if you have wood shingles, you can keep the shingles and place the hardboard directly on them or as I described with battens underneath to allow air between the shingles and the hardboard. Any water that may get in under the tiles, whether clay or concrete, should find its way down onto the hardboard and out from the roof or evaporate. Normally, a 45-degree pitch is used to utilize hardboard, but down to about 30 should work. You mention relatively low pitch, which probably means you will remove the shingles and install boards and felt, or remove the shingles and set up a "new sub-roof" directly on the trusses. I don't think tile manufacturers recommend their tiles for very low pitches. Perhaps you could use metal instead for the extension? // Micke