Our ~ 55 year old, mud brick house has a roof with 75% clay tiles. The other part is fairly new fiber-cement/asphalt corrugated roofing.
The structure of the tile part of the roof is a pretty typical A-frame made from some sort of roughly milled, apparently rot resistant wood that I guess could be as old as the house. Running across this is 1.25"x2" boards, some sort of pine, that isn't nearly as rot resistant. Generally, at least now, some sort of preservative is painted onto the wood used in roofs, but apparently wasn't used here, or else isn't very effective. Laid onto these support boards are your standard fired clay roofing tiles.
The problems we are having is that some of the support boards have rotted, and thus need to be replaced at least, because it causes sagging, leaking tiles. Even where the support boards are fine, tiles seem to shift and/or crack off little bits of the edges and/or water just somehow wanders a bit around the edge of the tile, and either leaks or rots the boards.
Clearly I have to replace many of the support boards, and use on all of them some sort of preservative, hopefully without very toxic chemicals in it.
Then my options are to replace the damaged tiles, taking from stacks of roofing tiles around here saved, I guess, from when part of the roof was replaced with the fiber-cement corrugated stuff, and hope that if the roof is very even it won't develop similar problems or replace the tiles with standing seam metal roofing, which the materials at least will run something like 3-4€/ square meter, plus some sorts of hand tools to make the seams.
I see a lot of fairly old standing seam sheet metal roofs here that look to be in good shape with just some minimal maintenance of painting them every few years. On the other hand, there are some clay tile roofs that seem to hold up well, like a neighbor's barn for one that I don't guess has had tons of maintenance done to it.
Other than the price advantage (piles of them lying around for free) and aesthetics, do clay tiles have anything going for them? We would consider something else as well, as long as its cost doesn't exceed metal and is fairly straightforward for a couple of people to do.
Clay tiles also have insulative value. Heat goes right through metal roofs BOTH ways, depending on the season.
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