Exposing old cut stone in farmhouse

Farmerjo

Was just looking for any advice. I have an old stone farmhouse that was built around 1800. It has pebbledash finish on it now but this is easily chipped off. I have chipped off a bit of this and there is cut stone underneath. Was just lookin for advice on weatherproofing, dampness and also who does this type of work. Any help would be much appreciated. Thanks

BryanF

If it's plastered the stone was never ment to be exposed.

Farmerjo

It was only plastered approx 30-40 years ago

Dudda

BryanF wrote: »

If it's plastered the stone was never ment to be exposed.

Not necessarily as it could have been plastered only 20 or 30 years ago.

If the stone underneath is in good condition you can remove the plaster and expose the stone. It would have been originally lime pointed and you will need to rake out the existing joints and point with lime render. This allows the walls to breathe and dry out. If you use cement you will trap moisture within the wall. You can dryline internally and insulate but you will have to ensure the stone wall internally is ventilated. Is the wall plastered internally and if so with what?

Edit: another thing to check is of the wall has a natural DPC. Natural slate was laid horizontally in the wall to act as a DPC and reduce rising damp. See if you can fine this and what height it is at relative to floor and external ground level.

my3cents

Unlikely the stone was ever meant to be exposed its just a matter of luck if you take all the render off and find the stone work to your liking.

If the stone work looks good on its own then all you need to do is repoint all the joints to make it weather proof.

Damp coming up from below is another matter.

my3cents

I'd also check that the pebble dash didn't cover up changes made when say a new door or windows were put in 40 years ago. I could chop back all the render off our old place as the stone underneath looks good however I would also have a lot of work around the windows where concrete blocks when new windows were put in some 30-40 years ago and one window was blocked up.

whupdedo

Farmerjo wrote: »

Was just looking for any advice. I have an old stone farmhouse that was built around 1800. It has pebbledash finish on it now but this is easily chipped off. I have chipped off a bit of this and there is cut stone underneath. Was just lookin for advice on weatherproofing, dampness and also who does this type of work. Any help would be much appreciated. Thanks

take off the old plaster right back to the stone making sure to clean out all the joints between the stone (some people sand blast to bring up the stone cleaner) as for weather proof, it's stone , it will be fine. You will need to point all the joints with a weak sand cement and lime mix, something like 10 sand 2 cement 1 lime would be adequate using a minimum amount of plasticiser As this will allow the walls to breathe
As for damp proofing , it's unlikely that carrying out repointing will allow damp into the house unless it's been there before, rising damp is another thing entirely . I know their is a liquid product in use that can be pumped into the old walls just above ground level externally or under floor level internally. Maybe someone on here knows a company that carries out this work

And finally any stone Mason worth his salt would carry out this work or any competent person with experience in this type of work

Chisler2

Farmerjo wrote: »

Was just looking for any advice. I have an old stone farmhouse that was built around 1800. It has pebbledash finish on it now but this is easily chipped off. I have chipped off a bit of this and there is cut stone underneath. Was just lookin for advice on weatherproofing, dampness and also who does this type of work. Any help would be much appreciated. Thanks

If it is dressed (cut) stone then your farmhouse is one of the "grander", the double-walled "rubble stone" cottage being the other vernacular. It sounds as if the mortar is original and has been preserved under the modern cement render which you plan to strip. Damaged or missing areas of lime-mortar (often the side facing the prevailing wind and heaviest rains) can be replaced "like-with-like" by using NHL (Natural Hydraulic Lime) sold in powder form in sacks. Lime-mortar is hydraulic so allows the walls to "breath", absorbing and releasing moisture slowly and passing it (when the process is not obstructed by cement or polymers!) to pass from inside to the outside of the structure which should mean there is no trapped moisture leading to dampness. Five or six coats thin coats of lime-wash will weather-proof the exterior of the building. This, also, is porous. You need an experienced stone-mason with knowledge of using lime and of the Irish vernacular techniques.

There are a number of useful texts and websites on this. Have a careful read of Patrick McAfee's "Lime Works" (AE - Associated Editions, 2009) which is full of practical information and illuminating photographs.

ralc

Hiya,
Following this thread on. I'm renovating a 270year old 2 story farmhouse. The living plan will be upstairs open living and down stairs is bedrooms. The walls are excellent built stone walls, half meter thick, lime mortar pointed inside and out from original and it never had any rendering inside or out. It was always exposed stone. I'm going to leave the stone exposed on the exterior but interior I was only going to insulate the ground floor bedrooms and leave the stone exposed upstairs. I'm wondering will this be okay in terms of dampness, cold, condensation etc upstairs. I am insulating downstairs with about 150mm of stepped off 30mm standalone insulated stud wall and insulated plaster board. The gap will be ventilated. I've DPC and well insulated floor with geothermal underfloor heating on ground and first floor. The walls will be exterior repointed up with same lime n mortar and I'll be injecting a sealing compound into the full perimeter of the base walls.
I'd be very grateful for peoples opinions

dathi

ralc wrote: »

Hiya,
I am insulating downstairs with about 150mm of stepped off 30mm standalone insulated stud wall and insulated plaster board. The gap will be ventilated.
/QUOTE]

will the gap be ventilated to the outside?

ralc

The plan is the gap would be ventilated to the outside yes. That's if I go with this stepped off independent insulation that effectively builds an insulated sealed house within the old walls. It seems a bit sterile.
I've a younger conservation engineer who favors this and an old school builder whose more in favor of the more natural breathable type insulation materials like wood fibre, hemplime or calcium silicate and it was he who suggested that I could get away with leaving the stone exposed upstairs in the open living area and go with natural breathable insulation downstairs. The building does sit quiet elevated and the perimeter walls are going to be injected with a penetrating sealant so rising damp is not so much a fear nor is leakage due after repointing.
The issues expressed are a risk of condensation on the first floor walls due to large heat loss through the stone.

I've seen a similar house though that they did only insulate downstairs and the upstairs bare walls are bone dry even in mid winter. I'm in a bit more of a windswept seaward spot though but my thoughts on that is as much as it's wetter is windier and so better drying and if I found I had condensate problems I could always apply more insulation upstairs.
So if go for it an go with exposed walls upstairs I[m in a muddle of which insulation suits the ground floor better, the more modern type stepped off gap based insulation or the contact natural insulation?....

THE DON FANUCCI

BryanF wrote: »

If it's plastered the stone was never ment to be exposed.

what a statement. my god