Repairing plaster / finish on solid brick walls
Discussion
Hi all, looking for some advice, currently light renovating my first home - a mid-terrace cottage built around 1850.. Bit of a long post but I think it'll help to explain.
In the front room was knackered laminate wood floor, I removed that and the underlay, to uncover knackered engineering wood floor, which I also removed. However that required removing the skirting boards. They were scruffy anyway, but particularly around the front door (which is being replaced) as water had crept in over the years and buggered the wood floor, which had been covered up rather than replaced. But the floor's a different job..
Now removing the skirting did make a bit of a mess, which we (my dad and I) need to repair. It doesn't have to be a perfect finish where it will be covered by new skirting afterwards, however I am keen to use the right material(s) and method due to the type of walls.
The house is - to my knowledge - solid brick with no cavity. The front external wall has, internally, finish directly onto the brickwork, as does one of the adjoining walls (staircase side). The back internal wall, to the rear kitchen, has dot and dab (or similar, I think) plasterboard, as does the other adjoining wall (chimney breast side).
I've made this sketch with labels showing where the photos relate, hopefully it makes sense!
So for repairing against the brickwork, am I looking at sand and cement rather than a gypsum-based product, or is there an alternative? I'll probably need to remove some more of the damaged plasterboard on the back wall - my concern is do I 'fill' and repair with some new board, or just a skim / finish?
I should add - these were taken just after removal a few months ago, and the area around the front door where the skirting has been removed looks slightly damp, as the old engineered wood had basically turned damp and rotten over the years but had been covered up with cheap laminate. The room's been like this since before Christmas and appears to be dry throughout now - other than the uPVC door frame not being properly sealed around the brickwork (should be replaced ASAP), no real damp symptoms have revealed themselves as I can see it..
The mess on photo 15 is just where I'd started rubbing back the lumpy plaster job that was there previously..
In the front room was knackered laminate wood floor, I removed that and the underlay, to uncover knackered engineering wood floor, which I also removed. However that required removing the skirting boards. They were scruffy anyway, but particularly around the front door (which is being replaced) as water had crept in over the years and buggered the wood floor, which had been covered up rather than replaced. But the floor's a different job..
Now removing the skirting did make a bit of a mess, which we (my dad and I) need to repair. It doesn't have to be a perfect finish where it will be covered by new skirting afterwards, however I am keen to use the right material(s) and method due to the type of walls.
The house is - to my knowledge - solid brick with no cavity. The front external wall has, internally, finish directly onto the brickwork, as does one of the adjoining walls (staircase side). The back internal wall, to the rear kitchen, has dot and dab (or similar, I think) plasterboard, as does the other adjoining wall (chimney breast side).
I've made this sketch with labels showing where the photos relate, hopefully it makes sense!
So for repairing against the brickwork, am I looking at sand and cement rather than a gypsum-based product, or is there an alternative? I'll probably need to remove some more of the damaged plasterboard on the back wall - my concern is do I 'fill' and repair with some new board, or just a skim / finish?
I should add - these were taken just after removal a few months ago, and the area around the front door where the skirting has been removed looks slightly damp, as the old engineered wood had basically turned damp and rotten over the years but had been covered up with cheap laminate. The room's been like this since before Christmas and appears to be dry throughout now - other than the uPVC door frame not being properly sealed around the brickwork (should be replaced ASAP), no real damp symptoms have revealed themselves as I can see it..
The mess on photo 15 is just where I'd started rubbing back the lumpy plaster job that was there previously..
Edited by smithyithy on Wednesday 12th March 21:19
Edited by smithyithy on Wednesday 12th March 21:21
Cheers, I had a feeling sand / cement might be the option, been advised against gypsum-based product due to the type of walls.
I found some lime-based material by a brand called DryZone which seems ideal where you need some breathability and there's signs of salt, but it's a lot more expensive and I don't know if it'd actually be a better choice.
I found some lime-based material by a brand called DryZone which seems ideal where you need some breathability and there's signs of salt, but it's a lot more expensive and I don't know if it'd actually be a better choice.
I've repaired similar several times over the years - DIY to a pretty good standard is do-able but takes me longer than I want.
The fastest option would be to get a plasterer in to re-skim the lot - they'll use the right patching plaster to bring the big holes to nearly level, and then skim the lot to a brand new mirror finish. It'll look brand new and would take less than a day to do this amount of work.
If you don't want to get the plasterer in, then undercoat wise - I've found that plasterboard adhesive is easy to work with to bond onto bricks / plasterboard etc. Use this to fill the bigger holes to just under surface level.
Then use Easifill 60 from toolstation to "skim" it all - It's easy to work with (way easier than actual plaster), can be finished with a trowel / speed skim, and sanded until perfect.
The better you are, the less sanding you'll end up doing.
But with a bit of practice, you'll be able to get a near perfect finish with relatively little skill (or at least I can).
The fastest option would be to get a plasterer in to re-skim the lot - they'll use the right patching plaster to bring the big holes to nearly level, and then skim the lot to a brand new mirror finish. It'll look brand new and would take less than a day to do this amount of work.
If you don't want to get the plasterer in, then undercoat wise - I've found that plasterboard adhesive is easy to work with to bond onto bricks / plasterboard etc. Use this to fill the bigger holes to just under surface level.
Then use Easifill 60 from toolstation to "skim" it all - It's easy to work with (way easier than actual plaster), can be finished with a trowel / speed skim, and sanded until perfect.
The better you are, the less sanding you'll end up doing.
But with a bit of practice, you'll be able to get a near perfect finish with relatively little skill (or at least I can).
If you were completely re-plastering back to bare brick, yes, a renovating plaster would be a good call but if you are just patching, do as said above, bulk out the holes with sand and cement then use some sort of filler: it may be gypsum plaster on there already so using a renovating plaster just for patching would seem a bit pointless, plus it’s not cheap stuff.
Personally anything below skirting line I wouldn't worry too much, i'd fill using low expansion foam then cut back with a blade. Then fit the skirting using the foam (you only need a thin bead then prop it in place and wait for it to go off). In theory you could do this all in one step. Above sand and cement to fill out any deep gap then mix up some powered filler and skim over and sand back (repeat if necessary). Benefit of using expanding foam to fit the skirting is if you ever need to get it off you can run a thin blade down the back and cut through it without ruining the plaster as i've needed to do a couple of times
Edited by SEDon on Thursday 13th March 16:21
Thanks chaps. If it was really large sections of wall that needed doing I'd definitely look to hire a plasterer but as this is all below (or just slightly above) skirting level, I'm not aiming for a perfect finish as such, just want to make sure I don't introduce any issues with what I use.
I think the new skirting will be fitted by the company that will be installing the new engineered wood floor, but we need to put down some self-levelling compound first and obviously get the bottoms of the walls tidy before doing that..
I think the new skirting will be fitted by the company that will be installing the new engineered wood floor, but we need to put down some self-levelling compound first and obviously get the bottoms of the walls tidy before doing that..
Looks like its been replastered in gypsum at some point, and painted with a vinyl paint given the way its peeled off, at which point assuming you are not planning to rip it all out, as said I would be using a sandable filler such as Gyproc Easifill. Presumably the now removed skirting also also modern 80s pine or similar, rather than period fittings?
As said, I wouldn't worry at all about plaster missing below the skirting board, the skirting will just bridge it. Photos 8, 13, 14 etc.
Infact, I would be removing plaster anywhere that it touches the floor, to ensure at least a 10mm gap, its common for plaster to stop an inch from the floor, this is literally half the point of the skirting board.
Also, if your floor is now level, you might have to 'scribe in' the bottom of the skirting to suit the floor. Avoid MDF skirting!
As said, I wouldn't worry at all about plaster missing below the skirting board, the skirting will just bridge it. Photos 8, 13, 14 etc.
Infact, I would be removing plaster anywhere that it touches the floor, to ensure at least a 10mm gap, its common for plaster to stop an inch from the floor, this is literally half the point of the skirting board.
Also, if your floor is now level, you might have to 'scribe in' the bottom of the skirting to suit the floor. Avoid MDF skirting!
Skyedriver said:
Plenty of advice above, just like to wish you well on your first home and well done for tackling the work yourself. Satisfying and you're learning new skills.
Thanks mate, appreciate that 
dhutch said:
Looks like its been replastered in gypsum at some point, and painted with a vinyl paint given the way its peeled off, at which point assuming you are not planning to rip it all out, as said I would be using a sandable filler such as Gyproc Easifill. Presumably the now removed skirting also also modern 80s pine or similar, rather than period fittings?
As said, I wouldn't worry at all about plaster missing below the skirting board, the skirting will just bridge it. Photos 8, 13, 14 etc.
Infact, I would be removing plaster anywhere that it touches the floor, to ensure at least a 10mm gap, its common for plaster to stop an inch from the floor, this is literally half the point of the skirting board.
Also, if your floor is now level, you might have to 'scribe in' the bottom of the skirting to suit the floor. Avoid MDF skirting!
The removed skirting was all MDF, it was nothing special / period fortunately, just wasn't in great condition, although it was only really the length running from the hinge-side of the front door to the bottom of the stairs that had gone spongey as I think it'd just absorbed the water from the front door and floor over time.As said, I wouldn't worry at all about plaster missing below the skirting board, the skirting will just bridge it. Photos 8, 13, 14 etc.
Infact, I would be removing plaster anywhere that it touches the floor, to ensure at least a 10mm gap, its common for plaster to stop an inch from the floor, this is literally half the point of the skirting board.
Also, if your floor is now level, you might have to 'scribe in' the bottom of the skirting to suit the floor. Avoid MDF skirting!
That's not a bad shout about leaving a gap to the floor though, I was a bit confused / unsure as to how to actually do this...
This isn't really to scale but hopefully makes sense.. Dark brown is existing quarry tile floor, orange is the brick wall, yellow is the existing plaster / finish. Should I take the existing plasterboard / plaster finish up high enough so that when we pour the levelling compound (grey), it spreads to the brickwork while leaving a gap i.e. the little white square, therefore allowing the new skirting to be installed to roughly the same level, and the new flooring to slot under the skirting?
ETA: This is in the area of photos 6 / 7, the front wall...
If I were to patch in the broken up areas with something like sand / cement or foam etc it will fill that gap (in pink) and the levelling compound would spread to it, then the flooring and skirting would be fitted as such - would that likely cause bridging or increase the risk of any damp?
Edited by smithyithy on Friday 14th March 11:50
as said above easyfill is your friend here, and if carefully applied you wont even need to sand it where skirting is going.
Its fairly cheap stuff and if you need to sand it its easyer than plaster of normal filler.
A sparkie mate put me onto it years ago, and its all ive needed since then.
For deep holes build it up in stages with a pallet knife.
Im not the best decorator, but the places ive used it around the house,you wouldnt know.
Its fairly cheap stuff and if you need to sand it its easyer than plaster of normal filler.
A sparkie mate put me onto it years ago, and its all ive needed since then.
For deep holes build it up in stages with a pallet knife.
Im not the best decorator, but the places ive used it around the house,you wouldnt know.
smithyithy said:
The removed skirting was all MDF, it was nothing special / period fortunately, just wasn't in great condition, although it was only really the length running from the hinge-side of the front door to the bottom of the stairs that had gone spongey as I think it'd just absorbed the water from the front door and floor over time.
Fair, MDF is really an awful material for skirting boards, you get away with it if you have carpet etc, but where you have a solid floor/wall or are going to be mopping against it, even low grade knotty slightly twisted pine is a better material!smithyithy said:
That's not a bad shout about leaving a gap to the floor though, I was a bit confused / unsure as to how to actually do this...
This isn't really to scale but hopefully makes sense.. Dark brown is existing quarry tile floor, orange is the brick wall, yellow is the existing plaster / finish. Should I take the existing plasterboard / plaster finish up high enough so that when we pour the levelling compound (grey), it spreads to the brickwork while leaving a gap i.e. the little white square, therefore allowing the new skirting to be installed to roughly the same level, and the new flooring to slot under the skirting?
ETA: This is in the area of photos 6 / 7, the front wall...
If I were to patch in the broken up areas with something like sand / cement or foam etc it will fill that gap (in pink) and the levelling compound would spread to it, then the flooring and skirting would be fitted as such - would that likely cause bridging or increase the risk of any damp?
In a new build, you would have a plastic DPC in the brick, and a plastic DPM under the floor, with the latter running up the wall and sticking out at floor level, and then plaster board down to inch from the floor. Thus the floor and walls are full isolated from the ground, and the plaster is fully isoloated from the floor. And the skirting bridges the gap. Plus a cavity isolating the inner structural wall from the outer brick façade. This isn't really to scale but hopefully makes sense.. Dark brown is existing quarry tile floor, orange is the brick wall, yellow is the existing plaster / finish. Should I take the existing plasterboard / plaster finish up high enough so that when we pour the levelling compound (grey), it spreads to the brickwork while leaving a gap i.e. the little white square, therefore allowing the new skirting to be installed to roughly the same level, and the new flooring to slot under the skirting?
ETA: This is in the area of photos 6 / 7, the front wall...
If I were to patch in the broken up areas with something like sand / cement or foam etc it will fill that gap (in pink) and the levelling compound would spread to it, then the flooring and skirting would be fitted as such - would that likely cause bridging or increase the risk of any damp?
You wont have plastic under the floor, or a cavity, and the dpc in the wall my be somewhat compromised in places and or bridge by the floor.
So I would be aiming for something about like the lower image, I presume the leaving compound will actually be much thinner as well as presumable waterproofish, but if you are floating in inch thick layer I would use a close cell foam often called 'underfloor perimeter strip' to avoid any bridging.
Then a 10-25mm gap between the bottom of the plaster and the new floor level.
Yeah I'll definitely seek a better quality skirting - there doesn't even seem to be much of a price difference between MDF and other woods.
That makes sense re. the floor / wall though - yes the actual levelling layer will be much thinner, the current tile floor is somewhat crowned at one end, so it will be a case of bringing the overall level up to the highest point of that crown - at some points in the room the screed may barely reach the walls as it could be only ~1mm thick, but I do need to take levels to determine the actual amount needed.
I've seen some suggestions of using a grid of flat-head screws in the floor that you can place a level on and mark around the perimeter wall the required height of the screed, which makes sense..
We're probably looking at using something like the 'No Nonsense' products from ScrewFix, the cement-based stuff is suitable for 3-50mm and is about £18 / 20kg bag. That part I'm not too worried about as it's just mixing and pouring to a level, my bigger concern was as above, the interface with the wall, potential bridging etc.
But the perimeter strip makes perfect sense!
That makes sense re. the floor / wall though - yes the actual levelling layer will be much thinner, the current tile floor is somewhat crowned at one end, so it will be a case of bringing the overall level up to the highest point of that crown - at some points in the room the screed may barely reach the walls as it could be only ~1mm thick, but I do need to take levels to determine the actual amount needed.
I've seen some suggestions of using a grid of flat-head screws in the floor that you can place a level on and mark around the perimeter wall the required height of the screed, which makes sense..
We're probably looking at using something like the 'No Nonsense' products from ScrewFix, the cement-based stuff is suitable for 3-50mm and is about £18 / 20kg bag. That part I'm not too worried about as it's just mixing and pouring to a level, my bigger concern was as above, the interface with the wall, potential bridging etc.
But the perimeter strip makes perfect sense!
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