Lime plaster vs Gypsum

[Spoilt Victorian Child]

I've just had a guy round to quote on a bit of renovation, mainly based around a full re-wire. I really like the look of other places he's done, but he pretty much wanted to hack off *all* the lime plaster on walls he was adding sockets to (which is a lot of walls!), and either put dot n dab back, or replaster wall with gypsum.

His argument was the current plaster sounded hollow and if he cut channels for electrics, a lot of the surrounding plaster would fall off too - the wall would never be neat.

He also reckoned the steam used to get the wallpaper off will weaken the lime plaster, so for the ceilings especially ithe old plaster could just fall off (possibly on top of someone) - therefore better to take it all down and replaster with gypsum. This would involve losing 3 rooms of lovely original cornicing. :-(

I just don't like the idea of filling the house with gypsum, but at the same time I do want relatively smooth walls that don't have to be covered with textured paper to cover the bumps and cracks.

I've asked a little before about this topic, but I'm still no further forward. How do other people do it? My house is lime on brick for the walls, lime on lath for the ceilings.

 

[Penners]

If I understand you correctly, you have a chap who is basically an electrician making recommendations about the replastering of your walls, and in the process it sounds as though he is trying to make life easy for himself.

My recommendation would be to divide these issues into their correct compartments. The electrician can do the electrics, but a proper lime plasterer should do the plastering. If, in the course of chasing out channels for the cabling, the electrician causes a bit more plaster to fall off, then that plaster was going to need replacing at some point anyway. And if you've got a plasterer in to make good the cabling channels, it's not going to add hugely to the bill if the plasterer has to stray a bit further into other collapsed areas.

If the ceiling plaster is in a poor state, then perhaps it will indeed have to be taken down and fully replastered. But at all costs you should refuse to allow the cornicing to be destroyed.

This sounds like a job for a qualified lime plasterer who has plenty of period property conservation experience. Don't let an electrician loose on it.

Horses for courses.

 

[skier-hughes]

Look for an electrician experienced in dealing with older properties, with different ideas on how to get electricity to the places you want it. Not knowing the property, it may be impossible, but losing all that would be devastating.
I doubt using a steamer on wallpaper would loosen the lime plaster, our old plaster is rock hard!!

 

[plasticpigeon]

Hello. I agree it is not really for the electrician to comment on plastering. In my experience I haven't managed to save any plaster on the walls as it is so weak in lime in my house, but the ceiling plaster is haired and much stronger. If the wall plaster in your walls is very drummy it might have to come off as it is all to easy for the small area of drumminess to become the whole wall when you try and cut it back. If your ceilings are haired lime, I'm sure that even with significant cracks, there won't be any danger of plaster falling down. You certainly don't need to loose the cornice. I would get in a few plasterers and see if any of them offer more acceptable solutions. I must admit I got a room in my house gypsum plastered as it wasn't damp and the last lime plasterer I had in was crap. The guy who did the most recent job in gypsum did do solid plastering though, I would draw the line at board and skim, but it's all personal preference.

 

[Flyfisher]

Look for an electrician experienced in dealing with older properties, with different ideas on how to get electricity to the places you want it. Not knowing the property, it may be impossible, but losing all that would be devastating.

I agree. I've installed a number of new sockets in a room with a suspended floor. Rather than cut into the lime plastered walls, I fitted surface boxes to the deep skirting board. The result was quicker, less destructive and the sockets themselves are far less noticeable against the skirting board than they would be inserted into the walls. I'm not suggesting this would always be suitable or to everyone's taste but just mentioning it as an example of Skier's suggestion to look for alternatives.

And yes, I know there are regulations about the heights of new sockets . . . . in which case they were already installed m'lud and this post will self-destruct in 20 seconds. :wink:

 

[drpepe]

I agree that steaming a lime wall can really damage it - has happened in our hall.

Despite the very weak and crumbly lime, our electrician had no issues routing cables for our rewire. I then patched with ... gypsum. :x

I'm not touching the cracked ceilings though... i don't think they'd take the weight of a gypsum skim.

 

[JoceAndChris]

Don't let your lime plaster and cornice go! It's irreplaceable! Lumps and bumps are lovely, part of the charm of an old building. Cracks can be filled. Don't listen to bad advice from this guy.

 

[mims&pip]

I agree with the other posters insofar as I wouldn't let my electrician - however good he might be at his own trade - to bamboozle me into losing original lime plaster.....especially original cornice :evil:

At our last house (non-rustic Georgian thatch) we didn't face this issue as the PO had already stripped most of the lime plaster back to bare stone - his intention being to create a delightful Disney-esque, cave-like interior more suited to the small cottages in our village - so our electrician had carte blanche to run his cables/trunking where he needed before replastering (mainly in lime) took place.

However, in a previous (Victorian) house our (different) electrician was faced with the task of rewiring a house that had been converted from a single dwelling to four flats and we were restoring it to a family home. He had no qualms about channelling out the lime plastered walls and at no point did he suggest stripping everything back to the brick. If he had we'd have given him very short shrift :roll:

Mims x

 

[MatthewC]

However, in a previous (Victorian) house our (different) electrician was faced with the task of rewiring a house that had been converted from a single dwelling to four flats and we were restoring it to a family home. He had no qualms about channelling out the lime plastered walls and at no point did he suggest stripping everything back to the brick. If he had we'd have given him very short shrift :roll:

My electrician was very good, but his lad had this little kanga hammer thing and I found him once starting to use it to chase a channel on a bare wall made of solid blocks of limestone. I stopped him and said "let's put that socket on this side of the door instead, as it's brick there". That was the same lad who had no idea of how to lift old floorboards and who had the ability to fill several rooms all at the same time on his own. The worrying thing is that he has a small son now...

NB I wouldn't want to chase a cable into a lime plaster wall unless I was really sure of the plaster - it would to easy to end up with a loose wall of plaster and a channel two or three feet wide.

 

[Penners]

this little kanga hammer thing

Do I detect an A A Milne obsession?

 

[Zebra]

D'you know though, at the same time, there are an awful lot of owners of period properties out there, who don't give a monkey's about lime plaster, laths, limestone or any of the rest of it.
I regularly cut holes for downlighters in lath and plaster ceilings, for property management companies who are renovating turn of the century properties in order to get better rents. I don't want to, but I do. It all gets filled in gypsum, reboarded if necessary. Cornices lost, whatever. Most people want clean lines, a modern look.
I'm just saying because it's not the tradespeople's fault. It's us, as owners, who have to make up our minds what we want, and then find the right tradespeople to do it.

 

[plasticpigeon]

That is true, there are a lot of ignorant homeowners out there. I know you are a tradesperson Zebra, and I'm sure your suggestions are always intelligent, tasteful, and sympathetic, but there are also a lot of trades people that are ignorant and cack handed that would rather destroy something beautiful than turn down a job. I have been absolutely clear and certain about how I wanted jobs doing in my house, even going to the extent of making drawings for bricklayers, and getting in specific materials for various people, and have still ended up with a total mess of a job. It was also interesting that when asking people that i know whether they would recommed their tradesperson, nearly all said no, which is worrying as I am fussier than most too. That said, I have found 2 really good people, a gas fitter, and the latest plasterer.

 

[Spoilt Victorian Child]

Thanks guys - I get what you're all saying.

I started peeling away some of the wallpaper in the lounge and was surprised to find that even though the walls were lumpy, it had been replastered in gypsum anyway. (Could just be a skim coat I suppose). I've yet to check the ceiling.

there's still the hallways and bedrooms though, which I think *are* still lime. I think my stumbling block is going to be finding a 'respectful' electrician in my area, or even a lime plasterer. Until very recently our houses were relatively low value, and every other one rented out (where landlords just want the quickest/cheapest job). Consequently the type of local tradespeople are largely bodgit & fixit outfits.

Does anyone have any recommendations, or suggestions of where I should be looking for quality tradespeople? I'm based in East London.

 

[TheRoost]

Totally agree with Penners, would even go the extent of having the walls channelled out with extreme care by a good lime plasterer or joiner who understands and respects what you are trying to preserve, so that all the electrician has to do is run cables and fit the sockets.

 

[Zebra]

I agree with Penners too, get the wiring sorted and if the plaster falls off, well it falls off, but then at least the electricians aren't tempted to encourage it to fall off, if they're not making good.
I might be able to help with some contact details for electricians, I'll send you a PM later. Lime plasterers in the area I don't know, but there are more around than there used to be...

 

[Feltwell]

I found that cutting chases with a wall chaser - which is a bit like a circular saw, except it has two diamond masonry blades spaced slightly apart - was much kinder to delicate plaster than just going for a hammer and chisel. A lot easier too, but you *must* use them with a decent vacuum attached and wear a good dust mask! Diamond blades are so efficient they go through the plaster like a hot knife through butter, and don't stress the surrounding plaster. You then just chip the middle section out with a small cold chisel.

http://www.amazon.co.uk/Silverline-817089-Silverstorm-Wall-Chaser/dp/B00E981AR6

Afterwards, making good with a good powder filler like Gyproc Easifill was a quick and fairly simple job, as you've a very neat chase to fill.

Alas my wall chaser is no more, the armature burnt out, scared the living daylights out of me when it happened!

 

[xanthe]

Try asking SPAB for recommendations. They were v helpful to talk to. Otherwise, try the CO in your borough.

If all else fails, then Rated People might be worth a try as you can spell out your requirements and level of pernickety-ness in advance. We once got a plumber through them - best one we ever found.

 

[JohnArmer]

Interesting what he said about wallpaper steamers damaging the lime plaster. When I stripped the wallpaper in my bedroom, I found that a wallpaper stripper was perfect for removing the wallpaper and the thin, 1960s-applied skim of gypsum, leaving the original lime plaster underneath intact.

I went ahead and removed all of the gypsum that way and my plasterer re-patched and re-skimmed everything in lime and it's perfect now. It's going to be the way I do every room that has been treated like this (which, to be fair is almost all of them).