Tony Williams

What is the received wisdom on how long to expect a Victorian slate roof to be serviceable? I have seen figures of 140-180 years cited, but no source given. In comparison, how long would I expect a replacement roof using modern materials to survive? This is what I think I need to understand to make an informed decision. Grateful for anyone who can give me some insights.

I have a mostly original late Victorian slate roof (1888). Some patching where a chiney has been taken out and a few tiles replaced over the years. It has no felt. But it's dry. Joists are good. I had an "MOT" a few years ago to make sure it was sound. I am exploring the fitting of solar panels and some contractors (by no means all) are baulking at fitting on such a roof. One has cited the 2010 Building Regulattions Part C - 6.2 Roofs should: a. resist the penetration of precipitation to the inside of the building; and b. not be damaged by precipitation and not carry precipitation to any part of the building which would be damaged by it. 6.4 Any roof will meet these requirements by being weather resistant and is backed by a material which will direct precipitation which enters the roof towards the outer face as with roofing felt and membrane. I thought OK, I'll get some quotes for a new roof. I'm in the process. But I also find from a bit of research that old slate roofs have quite a long life, and new roofs less so. I'm puzzling over what sort of a gamble I am taking here. Stick or twist? I'd be interested in people's reactions to this dilemma. Kind regards Tony