Surely the timber repair is completely unknown though? Fortunately ours were all Georgian oak and were like iron bars, extraordinary. Nothing needed replaced except a tiny section of 1980s repair that had rotted out!
Hope you'll be equally lucky with the timbers xanthe.
Yes, gorgeous to live down there but I'd expect 10 or 20% more on prices.
We had to get 30% more antique slates as the roof had been re done in the 80s ( using all the slates on it but buying in no more) with a woeful insufficiency. I think that can happen with period roofs when previous owners have done skimpy jobs. When you have ALL your roofer quotes saying you need 30% more slates you know it must be true.
As for cleaning, it's a personal choice, we went for minimum intervention and cleaning on the slates to keep the antique look.
Our roof is also quite big for the size inside as it's single storey in a lot of bits - so rather sprawling - though there is a little attic bedroom and a basement.
Your dormer sounds complex but yes if you can reduce the proportions it sounds like it will restore the harmony of the building. I think it's a shame when you see great big ugly dormers.
All the best with it, a lot of stress but so worth it.
Our roofers were lovely and brought their own loo and kept themselves to themselves, hope yours will be equally respectful.
One thing that worked well for us was agreeing a base price, and then also agreeing a fixed "menu" of costs where needed. We had horrible pantiles, which were a hodge podge or suppliers and colours from repairs over the years, and as a result didn't interlock properly, so went for new clay double romans throughout (matching the rest of the street).
I negotiated with the roofing company for him to take away all the old tiles and sell them to a reclamation yard, and then take that off the final price. Yes I would have got more if I had sold them myself, but it saved me the hassle. Based on that he gave me a fixed price of £13k, which included the leadwork and re-laying the central valley so the water actually flowed the correct way.
Finally, as we weren't sure of the condition of the timbers, we agreed a menu of prices for any possible bits that might come up along the way - £20 inc VAT for each rafter that needed replacing, £100 per repair/replacement if any of the ridge timber needed work.
They worked 6 days a week and completed the whole thing in 2 and a half weeks. Very happy with the roof since, and work also included a 10 year guarantee.
While the scaffold was up I'd nip up in the afternoons/evenings, tidy up some of the eaves insulation while access was easy, and renewed all the guttering myself, which was a lot cheaper!