drylining 2ft stone wall internally?

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moneydrains

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Hello all, This is my very first post and am hoping some of you can share experience or knowledge of old stone walled houses. I bought an old house about 7 years ago- its approx 250 years old. it had it's internal face of the external walls lime plastered. Well, actually they had lime plaster but it was damp and falling off all over, so we built a french trench externally and got some specialists to re-do the lime plastering. However, 7 years later we are freezing in the house. Back tracking a little -the walls are approx 2 foot thick - they have a painted pebble dash outside (which we are not allowed to touch), as the house is listed. I must confess that both my hubbie and I have a soft spot for our heritage and this is why we went down the reapplying of the lime plaster (it had been recommended we dryline at the time), but we read something about breatability issues and were recommended elsewhere to go dow nthe lime plastering route. 7 years on we are frozen - we spend a fortune heating the house, the heat loss is phenomenal - the timber boarded ceilign i nour bedroom is turning black - we wipe it down (clean it) and it comes back 2 weeks later full on.. The walls constantly have water dripping down them - the windows the same. I am wondering is it possible to
1. insulate my attic area - there is only crawling space (very small attic room)
2. put battens and insulated boarding / plasterboard up through existing ceiling boards (original white painted timber )
3. put some bubble wrap type lining and maybe foil backed insulated palsterbaord on the walls

or

is our problem much bigger than this ?
Any thoughts, suggestions, experience, professional knowledge very much appreciated.

Thanks
Sinead
 
I'm in a similar situation. Old house with stone walls that we are renovating. It's cold and suffers from bad condensation / damp as well. Not lived in all that often but our aim is to make it liveable full time.

It's very interesting to hear that you're spending a fortune on heating. We've been told that we need to dry line with insulated slabs as otherwise we'll be constantly heating the house. Sounds like our builder is right.

We did consider lime rendering but the cost was prohibitive and by the sounds of it we'd be spending the same amount again on heating pretty quickly.

I can't give you a definitive answer except that it sounds like you need to add vents to the rooms to stop the condensation. Then dryline with insulation and insulate the attic. Our attic is essentially just a crawl space as well, but we're getting it further insulated (it already has about 500mm). Remember to vent the attic as well, ours is very damp with condensation.

I'm not a builder, just someone in a similar situation. Hopefully of some help.
 
There are a few things going on here, my comments are in no particular order:

1. The pebble dash is likely to be a cement based render, not breathable, and thus is trapping moisture within the wall which would otherwise escape to the outside (if you had a breathable lime based render externally).
The pebble dash on your house is almost certainly not original. Your walls would originally have been limewashed externally, so I am not sure why the Local Authority would have a problem with you reverting to a lime render on the external face if this was pointed out to them. You should look into this in any case.
Lime rendering should only be carried out by a specialist.

2. You have a problem with a lack of ventilation in the house, thus a lot of moisture is trapped in the air. This will condense on cold surfaces.

3. You have a problem with insulation, which results in the internal surfaces being cold, and thus inviting condensation.

4. You need to be aware of, and treat, the ventilation and insulation problems hand in hand to insure a healthy living environment. This is very important.

5. Drylining, if carried out correctly and carefully (i.e. fully sealed from the stone walls with a membrane) will work, but if it is done incorrectly it will lead to moisture build up on the inner face of the stone walls, which you won't see, won't be able to clean, and will lead to mould. This will cause problems with degradation of the building fabric, and may well aso have health implications.
Many builders do not seem to be aware of this fact.

6. In regard to the roof, you will need to ensure that when you insulate it you leave sufficient space for ventilation between the roofing felt above and the insulation below. You are very likely to need slate vents in the roof to ensure airflow over the insulation (thus pulling off any moisture which will build up in this area).
You should also double check if your roof is leaking or not.

I would suggest that in the first instance you contact an Architect or Architectural Technologist who has experience with old buildings of this type and ask them to carry out an inspection.

www.studioplustwo.com
 
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builders as mentioned above (generally at the bequest of clients) often offer inappropriate short term solutions.
I tend to agree the above re pebble dash.
as regards drylining: there are other options, I'm a fan of hemplime or the calcium silicate boards.

using petroleum based insulations is in appropriate in old buildings

lime has little insulation properties and its use for plastering traditional buildings + its natural & breathable properties should not be confused with our need of comfort/heat retention.

heat retention: insulation must be correctly located to avoid existing wall surface condensation which is a very real possibility with drylining. similarly ceilings/attic must be insulated correctly with the roof structure vented, complete sealed and separated from the internal heated space by use of a Vapour control membrane located above the plaster/plasterboard ceiling (warm side of insulation)

ventilation to reduce internal occupant generated moisture: hole in the wall vents can be used, but Demand controlled mechanical extract ventilation is better.

seek advice from an architect/technician with knowledge of hygroscopic calculations and restoration/conservation experience
 
hi guys, thanks so much for your replies. all points are very interesting . I was particularly struck by threebedsemis first point on the pebble dash. I will contact the co. co. and see if its possible to change our pebble dash - as this makes perfect sense regarding the breathability of the walls. I had never thought of this before .Although I had though if I drylined internally - would I be creating a wet space (mould developing behind and between the wall) - which would be worrying for a number for factors, of course. What is the seal you mention in point 5? is this like a bubble wrap layer ? i saw this on a renovation prgramme? But its not a sealant - its more of a plastic layer that ensures the moisture will not effect your drylining - even if their is moisture in your walls. So I guess it means if the wall becomes very wet, your drylining will still be dry - but this doesn't seem like a long term solution - fixing the external face by rendering and using a seal as you suggest makes perhaps more sense - i guess this allows the wall to breath externally - and the seal blocks the water coming in. How I can hear my husbands thoughts on the €€€ front - but this is necessity really for health and comfort..
I am interested in reading into the mechanical extract ventilation (on demand) system mentioned. I don't know much about these vents being put into older houses - natural or mechanical or how a builder would even start going through the walls. anyway i will do some research.
chabsey - i can't give much advice here -but i would say your builder is absolutely correct on the drylining of the house - if you want to live in comfort i would go for it given our situation.
my attic space is really a crawl space- so i am a tad confused at how we might approach the insulating - there is a papery looking blown in insulating in there at the moment - i think this needs out and a quilted type put in perhaps.
If I had known the amount of money involved in this old house - I'd have left it for someone else:( Thanks for all your replies - very much appreciated. It gives me somewhere to start researching.
 
Here is my bit - hope it might help a little,

We renovated an old house dating back to 1700's - we wanted the old character but we wanted to live in modern comfort - to be honest at the start I really didnt think it could be done however we did it.

Firstly if you have neighbours or houses in your area with similar problems or who have done renovations on similar houses speak to them because people have been overcoming these problems for years and you will find out about the pit falls .....

We had to start in our house in the floor because our foundation was very shallow so on investigation a lot of damp was coming up through the floor, so we dug this out and put in a new floor with insultaion, the stone walls inside were then strpped back and sand and cement (or similar) material was put on them and then an insulated plaster board were put on all external walls which were plastered we got new windows, doors the chimney had to be looked after and we got a new roof.

Now we have a very very cosy house - now I am not a builder so I am not 100% on the sealing of the walls - we have pebble dash on one external wall and this was not a problem for us - so I am not sure about this.

Before we started we knocked on doors in our neighbourhood and spoke to people about what they had done and they were more than willing to help when we explained who we were ect..........

Anybody who takes on a job like this or lives in an old house feels your pain.....good luck it can be done......

J
 
We used gutex insulation you attach it to the
Lime plastering and then do a skim lime plaster
Onto it. We did this on our house it it works great
Gutex is a breathable insulation used on lime plaster
Got this in Athboy it comes in different thickness sizes.
ALso we used Sheeps wool that we rolled out in the attic
We renevated our 250 year old house and if you need info
You can give me a shout. Do not dry line over lime plaster,
Lime needs to be able to breathe.
 
Hi amsaminee. I am doing a similar project and interested in lime plaster and gutex. Would you be able to provide me with details of suppliers and who advised you in relation to this. Thanks a million
 
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