Lime Plaster Skim. Help!

[MattChan]

Hi all - first time poster and rennovator here..!
We are currently renovating a 1930s house and have finally stripped the whole house of its dated wallpaper (woodchip galore!), revealing some reasonably good condition lime plaster. We don't have the budget to get the house professionally reskimmed with lime (perhaps we could afford gypsum but not keen on this) so figured we would give it a go ourselves.

Does anyone have some tips for a pair of virgin plasters who would like to reskim an existing lime plaster wall?

I expect this will be the first of many posts... thank you in advance!

 

[Lacan07]

Hi all - first time poster and rennovator here..!
We are currently renovating a 1930s house and have finally stripped the whole house of its dated wallpaper (woodchip galore!), revealing some reasonably good condition lime plaster. We don't have the budget to get the house professionally reskimmed with lime (perhaps we could afford gypsum but not keen on this) so figured we would give it a go ourselves.

Does anyone have some tips for a pair of virgin plasters who would like to reskim an existing lime plaster wall?

I expect this will be the first of many posts... thank you in advance!

Skimming old lime walls is the hardest substrate to tackle imo due to the combination of under estimating how dry the wall is (suction) and applying the plaster to thin. It will need a good drink depending on what implement you use to water the wall. I have a large garden pump sprayer so I start watering a few days before the skim, 3 or 4 times a day. If you use a garden hose/rose then that will deliver more water quicker.

How are your hawk and trowel skills? I would source some non hydrated (lime putty) lime plaster and find a less important wall to practice. Stay away from the NHL stuff, some of it isn't easy to use at all.

 

[Ashville87]

Since the property has previously been wallpapered, presuming you’ve found no damp issues along the way and the property is able to breathe on the outside would you think about lining paper to make the walls good for painting instead? We’ve just stripped our lounge and the plaster is in good condition but has hairline cracks so we’re going with lining paper before emulsion finish.

 

[Lacan07]

Since the property has previously been wallpapered, presuming you’ve found no damp issues along the way and the property is able to breathe on the outside would you think about lining paper to make the walls good for painting instead? We’ve just stripped our lounge and the plaster is in good condition but has hairline cracks so we’re going with lining paper before emulsion finish.

This

 

[a twig]

Skimming old lime walls is the hardest substrate to tackle imo due to the combination of under estimating how dry the wall is (suction) and applying the plaster to thin. It will need a good drink depending on what implement you use to water the wall. I have a large garden pump sprayer so I start watering a few days before the skim, 3 or 4 times a day. If you use a garden hose/rose then that will deliver more water quicker.

How are your hawk and trowel skills? I would source some non hydrated (lime putty) lime plaster and find a less important wall to practice. Stay away from the NHL stuff, some of it isn't easy to use at all.

Just to prove all of us have different lived experiences, I found skimming with a 1:3 mix of NHL2 to plastering sand an absolute dream and struggled much more when attempting the same with putty based plasters

 

[Lacan07]

Just to prove all of us have different lived experiences, I found skimming with a 1:3 mix of NHL2 to plastering sand an absolute dream and struggled much more when attempting the same with putty based plasters

Yeah, I've only ever used branded NHL plaster, mainly from Lime Green, and I think they likely put accelerants in it so Lime putty plaster was much easier for me.

 

[MattChan]

Skimming old lime walls is the hardest substrate to tackle imo due to the combination of under estimating how dry the wall is (suction) and applying the plaster to thin. It will need a good drink depending on what implement you use to water the wall. I have a large garden pump sprayer so I start watering a few days before the skim, 3 or 4 times a day. If you use a garden hose/rose then that will deliver more water quicker.

How are your hawk and trowel skills? I would source some non hydrated (lime putty) lime plaster and find a less important wall to practice. Stay away from the NHL stuff, some of it isn't easy to use at all

Our garden pump sprayer was a god send for removing the wallpaper so sounds like it's going to come in handy again! Is there a risk of damaging the plaster with too much water?

Never used a trowel before but have the whole upstairs to hone my skills (not expecting the best finish but hopefully something that's passable!). I was intending to use Mike Wye regency plaster as it comes pre mixed. Is there a benefit to using a lime putty over the regency pre mixed stuff?

 

[MattChan]

Since the property has previously been wallpapered, presuming you’ve found no damp issues along the way and the property is able to breathe on the outside would you think about lining paper to make the walls good for painting instead? We’ve just stripped our lounge and the plaster is in good condition but has hairline cracks so we’re going with lining paper before emulsion finish.

There's plenty of damp (and mould) but thankfully it's occurring due to leaks that we are in the process of resolving. I doubt the walls were particularly breathable with the 5 layers of painted wallpaper we removed!

We are considering lining paper but have been put off by the sometimes dodgy finish, which is perhaps testament to the individual applying the paper! Would it be advisable to use a clay paint over the top of the lining paper to allow breathability?

 

[MattChan]

Just to prove all of us have different lived experiences, I found skimming with a 1:3 mix of NHL2 to plastering sand an absolute dream and struggled much more when attempting the same with putty based plasters

This is the challenge as a novice! There's many ways to achieve the same thing...

Would you advise using a premixed skim, for example the Mike Wye Regency plaster? Thinking it removes one variable for me to get wrong...

 

[Lacan07]

Our garden pump sprayer was a god send for removing the wallpaper so sounds like it's going to come in handy again! Is there a risk of damaging the plaster with too much water?

Never used a trowel before but have the whole upstairs to hone my skills (not expecting the best finish but hopefully something that's passable!). I was intending to use Mike Wye regency plaster as it comes pre mixed. Is there a benefit to using a lime putty over the regency pre mixed stuff?

Not really, you don't want the wall sopping but you want it permanently damp and cold so that the plaster just sits there happily minding its own business like it would in a plastic plasterers bucket. That gives you the time to move it around. You'll need to rough the surface of the old lime up with a devil float if its got a smooth finish.

Buy a standard Marshalltown trowel, and don't bother with a flex finishing trowel, you'll do everything with your Marshalltown.

I've never used MW Regency plaster, I assume it would be lime putty based as its premixed. Branded NHL is usually comes in powdered form and is mixed with water.

 

[a twig]

A pre-mixed fat lime plaster is a hell of a lot less labour when you’re working on your own, that was the biggest plus for me, just needs a quick whisk in the bucket/bag, maybe a splash of water and you’re off and running.

Frankly mixing plaster yourself really isn’t rocket science so don’t get worried on that score, the biggest benefit is not having to down tools and spend 15 - 20 minutes wrestling with a shovel, wheelbarrow and mortar hoe every time you need a new batch

 

[Lacan07]

A pre-mixed fat lime plaster is a hell of a lot less labour when you’re working on your own, that was the biggest plus for me, just needs a quick whisk in the bucket/bag, maybe a splash of water and you’re off and running.

Frankly mixing plaster yourself really isn’t rocket science so don’t get worried on that score, the biggest benefit is not having to down tools and spend 15 - 20 minutes wrestling with a shovel, wheelbarrow and mortar hoe every time you need a new batch

I would 2nd this

There's plenty of fabulous people on here who mix there own plaster from scratch whether it be NHL, hydrated, or non-hydrated, and certainly save themselves some money in the process, but for me ready-mix is the way to go. Lime plastering is hard work, I can often start early morning and still be going when the street lights come on. And thats before you have start cleaning up!

 

[DaveG]

I’m in a similar boat to OP. Come the spring I’ll be wanting to start having a go at this myself. Leaving stripped walls to dry out/breathe over winter.
My thinking is provided you’re happy to accept things will go wrong initially and it’s a learning process, in the long term it will be a worthy skill learned and save an absolute fortune.
I’m not sure where you are based but I’m about a 2 hour journey from Ty-Mawr who run 2 day lime courses for beginners/home owners so planning on doing that in May25. All earlier courses sold out!

 

[Lacan07]

Definit

I’m in a similar boat to OP. Come the spring I’ll be wanting to start having a go at this myself. Leaving stripped walls to dry out/breathe over winter.
My thinking is provided you’re happy to accept things will go wrong initially and it’s a learning process, in the long term it will be a worthy skill learned and save an absolute fortune.
I’m not sure where you are based but I’m about a 2 hour journey from Ty-Mawr who run 2 day lime courses for beginners/home owners so planning on doing that in May25. All earlier courses sold out!

Definitely a good idea to attend a course as it will hugely accelerate the learning curve which is quite steep in my opinion. Just make sure the course suits your need, if your going to use pre-mixed there's no point learning how to slake lime.