Who rebuilds wooden gables?

The actual roof covering is a job for a roofer, this references to the part of roof that keeps the elements out, and the building dry. The main structure, the timber sections is a job for carpenter/general builder. It is unlikely like all the timber work will need replacing, unless the roof has been leaking for many years, and rot has set in. A good roofer will know from looking in the loft if the timbers are gone, and need replacing it’s pretty common sense and self explanatory when timbers are rotten. Hope this helps and clears up any confusion. Regards Frankie BT Roofing Services Limited

Builder or carpenter would be able to do this with ease. Remove all the existing timber cladding and then consider replacing with a maintenance free composite board.