morro

I have a builder tiling my terrace. I asked about external insulation for my kitchen roof, 20m2, the tiles are in a poor state. He suggested a sandwich insulation topped with sheets of undulating tiles. He said it was excellent and much cheaper than insulation and re.tiling! Any ideas?

bons

Is it expensive to have tiling done? In or out.

morro

It depends on who you have, how expensive the tiles are, and the m2, and if you pay cash! Only go on recommendation!!!!!

macliam

If the roof is more or less sound (and/or repairable) and the roofer/builder estimates that the structure can bear the extra weight, then it seems a good idea. A neighbour had their sound bit tatty terrace "resurfaced" and now has regular leaks due to the rework being poorer than the original.... disturbing an existing structure should be a last resort.

morro

The roof was renewed in concrete, but they put the old tiles back on about 20 years ago, without insulation! The roof is excellent. I just want the old tiles removed, insulation put on and water proofed and tiled.

macliam

If there is no practical or aesthetic reason why the "sandwich" is a bad idea, you'll probably find it cheaper to put new tiles than to remove the old ones and re-do (less labour and less possibility of error). The insulation value should be equal if the same amount of insulation is used and you end up with a double skin.

morro

How does the new insulation go on without removing the old tiles? Last year I went onto the roof to remove a lot of vegetation and broke several tiles! They need to be replaced.

macliam

Then I refer you to my first comment.... you suggest the existing roof is not sound. If it were, the builer might well use rockwool to even out undulations and then styrofoam slabs to provide both insulation and a base for the new tiling - have you asked him?