1770s Gritstone Damp Advice

[Jian]

Hi everyone

I haven't had any joy with the agony uncle and can't find similar advice in the forum so thought I'd pose the question here...

My partner and I are considering buying the attached Grade 2 listed 1770s cottage. It's part of a mirrored pair and the listed building index describes it as "Coursed squared
gritstone, slate roof. 2 storeys, 2 first-floor windows". It needs thorough modernisation and I'm quite prepared for a project, but my two main concerns are structural - it has extensive damp, and limited space.

1) Regarding the damp... I have been told there it's extensive through out the ground floor, although the vendor has recently "treated" it i.e. hidden it with water resistant plaster. Where the back wall is still exposed reveals the extent of the damp. I presume this is worse because the concrete back yard is around 2 foot higher than the floor level, and it's also on the shaded North side. I'm hoping I will be able to dig the yard out as the neighbour has.
The neighbour's house also has no damp course and just has a concrete floor, but in fact has an acceptable level of damp i.e. only slight discolouration and foistiness in cupbard. Among all the conflicting material, I'm reading that injection might not be effective in masonry and any damp work would in fact just encourage the moisture up the walls and in to the neighbour's property. That said, after lowing the yard, installing central heating, fixing the guttering and using breathable paint, I can't be confident it will be as dry as the neighbours.

From the materials and info I've given would any one be prepared to advise on the best practice for removing damp in a property of this period / style. Bare in mind the lower back wall probably needs rebuilding anyway due to cracks in the lintel, if that that makes it any easier to put a membrane in. I'd like to take any necessary steps before moving in, however I'm open to less drastic solutions and living in it for a while if ventilation is the key. I'd be happy to give anymore info if required!

2) Regarding the size... with a grade 2 listed building my assumption would be absolutely no chance of planning permission for an extension. However the back of the property isn't overlooked and the neighbouring property has a tasteful extension put on around 25 years ago. Can anyone advise on whether applications are flat out rejected on listed properties these days, or whether I could argue that an extension would be in keeping with the neighbouring property. Worth a try!

Many Thanks

Ian

 

[Zebra]

Well, I would say that you're thinking along the right lines with lowering external ground levels, fixing any guttering, using breathable finishes and then heating the house to see whether it dries out. External ground levels 2 foot higher than indoors sounds like a recipe for damp. Can you be sure though, now before you buy the house, that those measures will solve the problem? Well no. That's the thing with old houses. There are so many varying factors that there's really no knowing.
My house is perhaps a little older, and brick not stone, but faced with a similar problem I just had to try one thing after another until the problem was solved. But if you really feel like you love the house, are willing to take it on even with all its problems and can really see yourselves there, then you can just enter into it a little blindly.
When you say the house needs "modernisation" though, I do hope you're not meaning that you hope to rid it of its period character!
And agree not to bother with injection, it seems to do as much harm as good in old houses. Just do a search on here for it, you'll find out why.....
As far as the extension issue is concerned, no, applications are not flat out rejected on listed properties, many forum members have done them. But just because next door got permission 25 years ago doesn't mean you will now. You could contact your local planning office to sound them out on it? My local council has Duty Planning Officers that you can go and talk to on a Wednesday morning and talk through your ideas, without making an application.

 

[Keith Bowman]

I'm an ignorant sort of southerner bloke and know nothing about that type of construction but two things strike me: 2 feet is a heck of a lot of concrete/rubble/soil. Has the neighbour really dug the back yard down that much? And secondly, have a look inside the roofspace if you can. Assuming you mean the left hand house of the pair, the flashing around the chimney looks pretty suspect and the join of the roof against the wall of the other neighbour looks like a mortar fillet, although it might be perfectly satisfactory. But if you're fit and reasonably capable and prepared to deal with the challenges over a period of time, go for it - you'll only regret it later if you don't!

 

[andrew gayton]

Not sure that Jian said that neighbour had lowered the ground level?

 

[Roger H]

Hi Jian,

Your approach sounds sensible. If rebuilding a section of wall you might as well get a damp proof membrane under the reconstructed section - in the wall it can't do any harm.

Two other points - lead flashing appears to absent from base of chimney stack which can't be helping, and you might want to check position re what seem to be PVCu windows. Not typically granted listed building consent, possibly there at time of listing or possibly installed without consent - in which case make allowance in purchase price for rectification.

Lastly, being listed ought not to preclude a well designed, sympathetic extension if this can be done without adverse impact on the building. Try and sound out the local CO on your ideas first.

Good luck!