Plasterboard ceilings- yes or no?

[DaveG]

Hi all, first post here so apologies in advance if I’m not following forum etiquette in some way.
I’m new to owning an older and characterful home having recently moved from a 1980s built ex-council house with timber frame, brick skin and cavity walls.
I’m now the proud owner of a circa 1870s stone built detached home with bags of character but also some deep scars from poor building practices over the years.
I started out perhaps as a few of you did, stumbling across Peter Ward’s website, YouTube videos and his book - “The warm dry home”.

Due to this, some of you may well be slightly confused, concerned or even horrified at my sheer mention of plasterboard.

So I know generally speaking it’s seen as evil nasty stuff that shouldn’t go anywhere near an older house but my query specifically relates to ceilings.

If you have lathe and plaster ceilings that are showing signs they need attention, if you’re going to do it properly, what do you do? Assuming you’re not just trying to patch it up and make do, if you want to take the opportunity of an open ceiling void, tidy up plumbing and wiring, perhaps run Ethernet, what should you do? Plasterboard? Or are there still people out there that will do fresh lathe and plaster?
What are the advantages and disadvantages if you stayed traditional? Some other factors in my case:
- it’s not a listed building but is in a conservation area (internal changes are not restricted but it’s just to make the point that it is a building that requires some level of sensitivity)
- it’s not exactly a building that’s entirely traditional. I.e it’s had a modern kitchen extension of which has used modern building materials.
I mention this because if the only reason not to plasterboard ceilings is to keep the building entirely original then that ship has sailed. I do want to be accommodating in keeping character and not adding additional poor building practices but for ceilings specifically it seems to me that it’s less of a visual impact if I were to choose a modern material but it’s a little more predictable to work with. Enlighten me!
Thanks in advance

 

[Lacan07]

Hi all, first post here so apologies in advance if I’m not following forum etiquette in some way.
I’m new to owning an older and characterful home having recently moved from a 1980s built ex-council house with timber frame, brick skin and cavity walls.
I’m now the proud owner of a circa 1870s stone built detached home with bags of character but also some deep scars from poor building practices over the years.
I started out perhaps as a few of you did, stumbling across Peter Ward’s website, YouTube videos and his book - “The warm dry home”.

Due to this, some of you may well be slightly confused, concerned or even horrified at my sheer mention of plasterboard.

So I know generally speaking it’s seen as evil nasty stuff that shouldn’t go anywhere near an older house but my query specifically relates to ceilings.

If you have lathe and plaster ceilings that are showing signs they need attention, if you’re going to do it properly, what do you do? Assuming you’re not just trying to patch it up and make do, if you want to take the opportunity of an open ceiling void, tidy up plumbing and wiring, perhaps run Ethernet, what should you do? Plasterboard? Or are there still people out there that will do fresh lathe and plaster?
What are the advantages and disadvantages if you stayed traditional? Some other factors in my case:
- it’s not a listed building but is in a conservation area (internal changes are not restricted but it’s just to make the point that it is a building that requires some level of sensitivity)
- it’s not exactly a building that’s entirely traditional. I.e it’s had a modern kitchen extension of which has used modern building materials.
I mention this because if the only reason not to plasterboard ceilings is to keep the building entirely original then that ship has sailed. I do want to be accommodating in keeping character and not adding additional poor building practices but for ceilings specifically it seems to me that it’s less of a visual impact if I were to choose a modern material but it’s a little more predictable to work with. Enlighten me!
Thanks in advance

Welcome,

Many people use modern gypsum on ceilings, if you have a failing lath & plaster ceiling or you need to remove it in order to gain access to the void then replacing with plasterboard is fine. Modern plasterers are also happy to skim lath & plaster ceilings as long as they're sound any wallpaper is removed.

The only downside to removing a lath & plaster ceiling imo is you do lose some its sound proofing qualities. Its usually applied pretty thick in the traditional 3 coat system and with the multiple strips of lath its can be quite effective at noise reduction compared to 9 or 11mm plasterboard. With this in mind it might be better to try and save it by skimming over the top or wallpapering.

If you really are intent on removing a lath & plaster ceiling I really wouldn't bother with the expense of hiring a traditional plasterer to replace it unless your in a listed building.

 

[DaveG]

Many thanks Lacan, that puts my mind at ease that it wouldn’t make me a terrible person
I have heard it does offer far better sound proofing so will bear that in mind.
When replacing all floorboards in my last place I took the opportunity to add sound insulation so that’s always an option to help mitigate that a little bit.

Thanks again

 

[malcolm]

There are some advantages to lath ceilings:
They don't fall down when the shower leaks above. They get wet and drip but dry out again when the leak is fixed. Plasterboard isn't tolerant to leaks.
They are easily repairable - if some plumber has made a bunch of holes just knock a bit of plaster off, attach a new lath or two, then plaster back over.
If you have lining paper on them the lining paper can be removed to get back to the bare lime in future decoration. Plasterboard would be damaged.

I've kept all of mine and just repaired them.

It's better to organise access to services from the floor above so changes can be made later without tearing down all the ceilings.

 

[DaveG]

Good points. On the subject of lining paper, is this what everyone does with their lime plastered walls and ceilings? I guess not an issue for ceilings but for walls particularly (mine are holding a lot of moisture at present) I thought paper would be preventing breathability so my longer term plan is to remove all paper. I realise that this leaves quite a grainy finish but I’m guessing that’s something to be embraced when adding your clay based paints or I’m not sure whether there are more modern lime based skims that get you closer to a bit of a smoother finish?

 

[paulc]

My thoughts on plasterboard versus lath & plaster:
Plasterboard doesn't crack in random places, but it can crack along the joints if not properly screwed & taped.
It is (relatively) quick & easy to put up (well, the 6x3 sheets are), and any plasterer is happy to put a skim coat on.
Downside - It doesn't suffer damp & water very well.
SoundBlock plasterboard may be better at absorbing noise than regular plasterboard, but it is heavier and more expensive. Double thickness will improve the sound blocking properties.
You can skim plasterboard with lime as long as you use a bonding coat first. DG-27 is often recommended, but I find FeBond Blue Grit to be just as effective.

Lime plaster is much better in coping with damp and water, but when the laths expand, it causes the plaster to crack.
Long term, unless stainless steel nails are used, the nails can rust and eventually fail.
Lime plaster is inherently fire and heat resistant (good round wood stoves).
A thick coat of lime plaster absorbs noise better than plasterboard.
Finding someone able & willing to work with lime is not easy, and when you do, they charge a premium.
Lime plaster is much slower to set - With putty based plasters, as long as it is damp, it doesn't go off. That gives you plenty of time to work unlike gypsum.
Mix a tub of lime putty plaster, and as long as there is a bit of water on the surface, you can store it somewhere cool for an eternity. Just give a good mix before using it.
Taking down an old lath & plaster ceiling is an extremely messy and dirty job. You need a good quality dust mask when pulling a ceiling down.
Lime plaster can be reused as MOT1 should you want to lay a shed base or patio.

For my sins, I've been replacing the old lath & plaster ceilings here with plasterboard. The kitchen was skimmed with a lime plaster and seems to be coping with the elevated humidity levels. May well use a moisture resistant plasterboard if/when I get to do the bathroom (with a lime skim).

 

[DaveG]

Interesting someone would use a lime skim with plasterboard. I didn’t think anyone would do that but I can see the appeal if it stands up to damp better.

 

[Lacan07]

Well the standard gypsum plasterboard does have breathability funnily enough but as others on here have already mentioned it doesn't cope well if it gets damp.

 

[paulc]

Interesting someone would use a lime skim with plasterboard. I didn’t think anyone would do that but I can see the appeal if it stands up to damp better.

Lime skim for two reasons - Hadn't mastered the dark art of gypsum plastering, and could take my time getting a smooth finish. The finish coat was a polished Venetian plaster, so i could go straight on to the lime plaster without using any expensive primers.

 

[Oldhouseman]

Hi Dave, hope you haven't already fitted plasterboard and the devils own work, gypsum plaster! There are many reasons to not do this, but one that rarely gets mentioned is appearance. It's too smooth, hard and cold. In an old property, it simply doesn't look right. You can end up with an old house that all looks new. Nobody fits new laths unless it's grade 1 listed. Wood wool board is the way to go, along with lime plaster. There is some misinformation above. Lime putty takes a long time to set, indeed it will last forever if kept wet. NHL limes will only last for a few hours once mixed. For ceiling work, I would use 2 x coats of NHL3.5 with a GRP mesh in between and 5 days later, 2 x very thin coats of a premixed fine lime plaster made from putty. The paint is also a very important consideration.
I should imagine your walls are damp from the devils best friend, cement. But that's another story.

 

[DaveG]

Thanks for this. I’ve done nothing to ceilings as yet so am pleased to have got your response to this. It’s still very much on my to do list but it’s competing with other priorities as I guess is often the case with taking on an holder house

 

[Kearn]

Hi Dave, hope you haven't already fitted plasterboard and the devils own work, gypsum plaster! There are many reasons to not do this, but one that rarely gets mentioned is appearance. It's too smooth, hard and cold. In an old property, it simply doesn't look right. You can end up with an old house that all looks new. Nobody fits new laths unless it's grade 1 listed. Wood wool board is the way to go, along with lime plaster. There is some misinformation above. Lime putty takes a long time to set, indeed it will last forever if kept wet. NHL limes will only last for a few hours once mixed. For ceiling work, I would use 2 x coats of NHL3.5 with a GRP mesh in between and 5 days later, 2 x very thin coats of a premixed fine lime plaster made from putty. The paint is also a very important consideration.
I should imagine your walls are damp from the devils best friend, cement. But that's another story.

Can’t agree with this - NHL3.5 indoors is way too hard, and NHL can happily sit in a trug for ages, with just a covering of water to stop it carbonating. It’s still forgiving to work with. That much plaster on a ceiling is excessive and heavy. And far more work than anytime need to be doing overhead!

If you’re going onto lath, then a nice haired putty mix is needed to help the integrity - same goes for woodwool boards. With the right aggregate, you can get away with a base coat of 6-8mm or more if required, then a few mm skim on top for the finish coat.

Laths certainly get used in other buildings than just Grade 1, why wouldn’t they. Sometimes it makes more sense, especially with repairs where discrete patches can be sorted retaining the existing fabric in situ. Pulling everything down is rarely the right answer, it’s also hideously messy.

Plasterboard and modern materials aren’t always ideal, but sometimes needs must for various reasons - ceilings you’ll do no real harm by going this route. In a bathroom or kitchen you may prefer the moisture managing properties of lime. In terms of appearance, there’s a bizarre myth that old houses had wobbly plaster everywhere, which is a disservice to the craftsmen if their time - I’ve seen many incredibly smooth, and consistently thin finishes, happily going string after 400+ years. What you’ll also find on a ceiling with old joists, is that there will likely be some undulation when you attach the boards, if you don’t pack them out, which can avoid a completely flat surface.

 

[Oldhouseman]

Yes Kearn, you're quite right. I don't put 2 coats of NHL on the ceiling, only I which is haired, with the mesh pushed into that. I haven't done any ceilings now for a few years and I forgot. But NHL3.5 isn't too hard at all. Well, I hope not cause it's covering a lot of my house. And it's been doing it for many years now. I did have 1 crack open up by a kitchen window once. Incredible to watch it self heal. NHL3.5 is available in a lot of builders merchants these days, whereas a lime supplier will charge £40-50 delivery to order in NHL2. And as it does work, why not. This is from the St Astier guidelines.

'NHL 3.5 is a medium strength or “moderate” hydraulic lime. It is used where a respectable amount of free lime, (that which is responsible for self-healing), is desired along with an excellent modulus of elasticity and high vapor exchange is maintained for the NHL range.'

Interesting about your comments regarding covering with water. I've found this simply doesn't work. As do it seems most lime suppliers. 'Natural hydraulic lime is a type of lime that sets through hydration. It’s made from limestone that contains clay and other impurities, which give it hydraulic properties. Unlike non-hydraulic lime, NHL can set underwater and in damp conditions, making it highly versatile for various construction needs.' - from ecowise.com

'Laths certainly get used in other buildings than just Grade 1, why wouldn’t they.' Hmm, how about 62p a foot for riven chestnut. Plus the time to fit them. For sure, if its a repair of a small area. But the OP was interested in ceiling replacement. And plasterboard and gypsum plaster have no place in an old house. It's not about bizarre myths of wobbly plaster, it's amongst other things, the texture of the finished wall or ceiling, the way the light falls across it. Gypsum plaster is polished. Lime plasters, even the finer grades, have a slightly sandy, gritty finish.

 

[Stevers]

whereas a lime supplier will charge £40-50 delivery to order in NHL2.

If NHL 2 is what you're after then 50:50 NHL 3.5:Hydralime is another way to go, both should be available from your local merchant to collect as you need them.

The NHL3.5 plaster that I applied to my basement chimney breast ended up a bit too hard to take a picture nail, but that could have been the sharp sand (25% of the aggregate) or the stone dust (50%) of the aggregate. In all other respects I'm delighted with what it's achieved in drying out a problem area.