Lime plaster wall repair advice and more

[samberzina]

Hello,

Absolute newbie here, hoping to gain a little bit of knowledge!

My partner and I have purchased our first home, an 1880s victorian terrace. Definitely a lot of lessons learned already as the house is riddled with damp issues, years of neglect and poor bodge jobs. Despite all this, we absolutely adore it and are keen to give it some love and get it back to a good condition.

1. We have started stripping back the existing painted wallpapers and the substrate appears to be lime plaster (porous and fairly soft). Most walls so far are not in too bad of a condition with some larger holes to fill in and small indentations where the wallpaper coming off has taken bits of plaster off - photos attached. At its current state we do not think we would need to replaster fully. We have been looking at a product called Patchcote which is lime based and can be used for repairs - has anyone got any experience with something like this? Speaking to the manufacturer they suggested we can apply Patchcote with a trowel over the larger cracks / holes and then just apply a lining paper over (in 2 cross-layers). We would like to redecorate once the walls have been sorted out and worry a little that with a lining paper the lines where the paper meets would be visible and unsightly? Again, any tips or experience shared would be absolutely appreciated. Are there any other clever ways dealing with walls in this condition?

2. In some of the rooms there is an absolute hodge podge of modern fillers and gypsum plasters - again, the areas of lime plaster are in a good condition, however how do we deal with the gypsum / filled areas? Do we have to take it all off and refill / replaster or can we leave it as it, smooth it all out and apply the lining paper over?

Thank you in advance!

 

[Lacan07]

What you do will be dictated by where the walls are and / or whether they're damp.

Generally people tend to compromise on the upper floor walls that suffer less risk of water ingress / damp so they gypsum skim or wall paper, although some people like to keep the upper floor external walls breathable with lime.

In an ideal scenario people generally keep the ground floor walls breathable in an old house. So if you have damp issues on ground floor walls you firstly find the causes of the damp and fix it, make good the walls, lime skim, and then clay paint or lime wash to finish.

The walls in the photos don't look too bad to me but if you intend to apply wall paper and need to patch holes, etc, I wouldn't bother using some expensive, eco, lime product because most wall paper / paste doesn't breath and I wouldn't trust the ones that say they do. Others on here will no more than me about wall paper. If the walls don't need to breath then Easyfill will suffice for repairs.

If you intend to keep those walls breathable and decide to lime skim (or even you just wall paper) then I would bother removing any patches of gypsum above 1.5 meters as long they're not too sizeable and aren't causing any issues.

 

[samberzina]

What you do will be dictated by where the walls are and / or whether they're damp.

Generally people tend to compromise on the upper floor walls that suffer less risk of water ingress / damp so they gypsum skim or wall paper, although some people like to keep the upper floor external walls breathable with lime.

In an ideal scenario people generally keep the ground floor walls breathable in an old house. So if you have damp issues on ground floor walls you firstly find the causes of the damp and fix it, make good the walls, lime skim, and then clay paint or lime wash to finish.

The walls in the photos don't look too bad to me but if you intend to apply wall paper and need to patch holes, etc, I wouldn't bother using some expensive, eco, lime product because most wall paper / paste doesn't breath and I wouldn't trust the ones that say they do. Others on here will no more than me about wall paper. If the walls don't need to breath then Easyfill will suffice for repairs.

If you intend to keep those walls breathable and decide to lime skim (or even you just wall paper) then I would bother removing any patches of gypsum above 1.5 meters as long they're not too sizeable and aren't causing any issues.

Thank you so much for your response. In an ideal world we would love to lime plaster everything, however the quotes we got back just to deal with the external walls and some external work made my eyes water!

So what you are saying is that if we put a lining paper over the walls that would mean they would become non breathable? We were intending to use the lining paper just to deal with the imperfections over the wall and then paint over the paper with a breathable paint. I had seen some lining papers which claim to be breathable but I guess the issue is the adhesive that would be used? I know it can be very tricky to decipher what materials are genuinely breathable!

If we decide to skim over with gypsum (on the internal walls), is there anything specific we should be aware of - ie is there a chance that gypsum would not adhere to lime paster underneath, fall off etc? Thank you again for your response!

 

[Jahouli]

Had walls that looked very similar to yours once I stripped the old wallpaper off. My wallpaper had signs of mould around the windows and the humidity levels in the house were constantly on the high side, so I was keen to keep things breathable. I primed my walls with Baumit DG27, which is a breathable primer, and had a plasterer apply a lime plaster skim. I finished off with Earthborn breathable paint. I love the textured finish of the lime and haven't had mould or humidity problems since.

I can't really comment on the breathability of lining paper but I have read there is some doubt as to the claims. My two penny's worth is that lining paper can easily be removed if problems of any description arise in the future, whereas a gypsum skim would likely require compete removal back to brick/stone to reinstate a vapour permeable system.

The point made by Lacan07 about upper floors being less of a concern is valid though, although think it through carefully if the elevation is particularly exposed or a gable end (and therefore more likely to cold and suffer condensation issues).

 

[Lacan07]

Thank you so much for your response. In an ideal world we would love to lime plaster everything, however the quotes we got back just to deal with the external walls and some external work made my eyes water!

So what you are saying is that if we put a lining paper over the walls that would mean they would become non breathable? We were intending to use the lining paper just to deal with the imperfections over the wall and then paint over the paper with a breathable paint. I had seen some lining papers which claim to be breathable but I guess the issue is the adhesive that would be used? I know it can be very tricky to decipher what materials are genuinely breathable!

If we decide to skim over with gypsum (on the internal walls), is there anything specific we should be aware of - ie is there a chance that gypsum would not adhere to lime paster underneath, fall off etc? Thank you again for your response!

Like I said I'm no expert on wall paper coverings but I wouldn't be using wall paper full stop on a wall I wanted to breath. As you say many people question the paper paste, I'm not sure I'd want the paper either. Thats just my opinion of course and everything is a compromise at the end of the day. Other on here may advise you differently.

I'm afraid one of the problems of any renovation, but especially old houses, is there is no clear pathway to follow for many of the tasks you'll encounter. Even within this shift in attitude as to how we treat old houses there's currently a debate about 'levels' of breathability within different lime plasters.

If you want to gypsum skim a lime wall your plasterer will prime it first with watered down PVA glue to aid adhesion. They'll always be the threat of slight cracking however as old houses move and gypsum absolutely doesn't. To be fair even Lime plaster cracks though.

 

[Lacan07]

The point made by Lacan07 about upper floors being less of a concern is valid though, although think it through carefully if the elevation is particularly exposed or a gable end (and therefore more likely to cold and suffer condensation issues).

As I said above I'd always lime plaster an external wall on the upper floors

 

[malcolm]

I'm a big fan of lining paper. It is perfectly breathable so long as you use a paper based lining paper not vinyl paper. Also use cold water paste not PVA. I think I used this lining paper: https://www.screwfix.com/p/erfurt-natural-red-label-double-lining-paper-560mm-x-20m/48424

Lining paper will reduce the prep needed so you don't need to skim plaster over your lime plaster. It can be removed at a later date should someone paint non-breathable paint on top.

For filling the choice of filler depends on the depth you want to fill. Use a lime plaster for major repairs. You can't sand lime plaster so for surface finish repairs I use a modern sandable filler https://www.screwfix.com/p/toupret-interior-powder-filler-2kg/390pp It's quick when you bung it on and then go over with a drywall sander.

The gaps between the paper can be hidden. Leave 1mm gap, put some paint on it and then fill it. The filler can be lightly sanded and the paint protects the wallpaper.