Hi all. The underfelt on my 1970 built semi has rotted and split in a number of areas and now there are a couple of leaks into the loft. The roof has interlocking concrete tiles and the house style is like the one in the picture. Ive had a roofer give a price to remove the tiles, felt and battens and replace with new. He's also given me a price to reuse the old tiles. Given the age of the house will the tiles still be ok, or should i replace them with new? The roof area is about 35sqm on each side and he has quoted £2400 to do the work reusing the existing tiles. Another £900 if I want new tiles. This is north east England Is that a decent price? Thanks for any help.