How bad could it be? (leaking roof)

[doogyscoot]

Hi folks, I've leant on the knowledge of this forum before so I hope you can help. We're looking at a house we want to buy in Stirlingshire and the survey indicated the roof has leaks, specifically round the chimneys and that the timber shows damp staining. There also appears to be some rot/decay around the dormers and some of the timber at the gables. It also mentioned there was woodworm but I'm not horrendously worried about that.
I don't know much about roofing work so was hoping some of you could give me an idea of whether the roof looks particularly bad externally and how much I could be looking at for getting the roof covering refurbished and woodwork repaired? I appreciate it will depend on lots of things but I'm just looking to see how bad it could be. I'm budgeting approximately 10-15k worst case scenario. does that seem dreadfully optimistic? View media item 88886 View media item 88887 View media item 88888 View media item 88889 View media item 88890 View media item 88891 View media item 88892 View media item 88893

 

[doogyscoot]

Sorry, forgot to add the images, they've been attached now.

 

[terrypin]

Can't give you an idea of cost as that would be a wild guesstimate.
What I will say is those slate will be probably be totally shot and not re-useable. I have done 8 reroofs in your neck of the woods(Stirling)and I was experiencing 80% loss when removing.

 

[doogyscoot]

Thanks, that's good to know, out of interest was that simply due to the age of the slate? When you were replacing, what type of slates were required? I wasn't sure if it would be Welsh slate up here, or possibly Scottish stuff from Ballachulish given the age of the property?

 

[terrypin]

The slates were local iirc, they hadn't weathered well and were very, very brittle and crumbled when lifted.
We replaced them with slate from a supplier in Montrose but it's a good few years ago(25?)so they may not be around now.
Sorry I can't be of more help.

 

[Alastairreid]

Regardless if the slates are shot there will be a good chance it will be nail sick anyway.

 

[doogyscoot]

Regardless if the slates are shot there will be a good chance it will be nail sick anyway.

Thanks Alastair. Fair point, if this was the case would I be right in assuming it would be a case of removing all slates and replacing the sarking, along with a new membrane then refixing slates (old or new as dependant on condition of current ones)?
Would it be pretty common practice to replace the sarking or only if there was rain damage?
Sorry for all the questions, I'm just trying to form an impression of how much we could potentially have to spend on sorting the place out. As stated above I was hoping the roof work wouldn't be much over 10k, 15k max. Ideally a bit under. For what it's worth, the roof is approximately 124m2 but there are 3 dormers on the front and 1 on the back.
Thanks again for the input so far.

 

[Alastairreid]

The slates may be reusable, you should be able to tell from the attic the condition of the sarking.

Best scenario, Slates are for the most part recyclable, sarking boards are serviceable, leadwork to chimneys and dormers will probably need renewed..Chimneyheads sound and the gutters and rainwater goods renewed.

I would expect change from 10k to get that lot done.