Slate Roof Torching
A new slate or salvaged slate which should match the size shape texture and weathered color of the old slate is then slid into place and held in position by one nail inserted through the vertical joint between the slates in the course above and approximately one inch below the tail of the slate two courses above.
Slate roof torching. The torching on clay tile roofs contributed to securing them in the days before nibs were added to hold them on the wooden battens. Lime acts as a sponge to hold water and release it as conditions change. Nearly all old roofs were lime torched. Although a slate roof is initially quite costly it will often last for a lifetime and beyond.
Slate roofs are no exception. 1 2 the gradual decline of the stone slate roofing industry has led to a loss of expertise of both roofers and specifiers and there is little written information available on best practice methods for. In the days before roofing felt torching or lime mortar was used on the underside of tiles or slates to keep them in place and to prevent strong winds from getting under the tiles and lifting them. Whether slate clay tile or stone flags lime was used to bed the tile or beneath them to prevent undue wind and hold condensation.
The homebuyer survey noted the torching was dropping away and would need attention in the next year or two reported as amber. We constantly battle to prevent roofers from stripping entire roof pitches just because they see torching and say oh an old roof without felt it needs felt. In the days before roofing felt torching or lime mortar was used on the underside of tiles or slates to keep them in place and to prevent strong winds from getting under the tiles and lifting them. Traditional variations of a physical secondary barrier against wind driven snow and rain include reeds laid between the tiles and the battens and a coating of mortar known as torching to the underside of the tiles or slates.
This system was commonly known as torching and was used before the introduction. This can be carried out cheaply and it s work you can comfortably undertake yourself. Torching is a lime cement weather seal traditionally used inside old slate roofs. Originally the only recognised roof under coating was the application of sand lime mortar reinforced with animal hair applied to the headlaps of double lapped slates or tiles.
Torching is most commonly encountered to the underside of old stone slate roofs. Quite a lot of it is missing and the rest looks like it won t last that long. Over the years this torching can crumble and break normally falling with a thud on the floor of the roof space during the middle of the night. Keeping the local stone slate roof of an historic building helps to conserve its significant character.