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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Building Questions >> Repairing a skim coat https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1136904729 Message started by CWatters on Jan 10^th, 2006, 2:52pm

Title: Repairing a skim coat
Post by CWatters on Jan 10^th, 2006, 2:52pm

Just pulled off some wall paper and the plaster skim coat came with it. I've removed all the loose stuff but now have an area about 3 square feet and between 1/8" and 1/4" deep to fill with plaster...

Whats the best way to go about this? Do I need to prime the surface first - it seems a bit dusty?

Last time I did any large areas I found it impossible to get it smooth and flat. Based on past form I think my best bet would be to pile it on then use a long straight edge to scrape it flat. Fill any hollows with a second coat etc.

Title: Re: Repairing a skim coat
Post by JerryD on Jan 10^th, 2006, 5:17pm

If it's just the skim coat that's come off, (leaving the backing coat intact), you should pva the patch (50/50 pva/water) then apply Multifinish.

Ideally two coats, one immediately after the other and trowel in.

Getting it flat is the skill that takes 5 years to learn.......

You won't need a straight edge for skim coat, you should be able to 'feel' the flatness by the way your trowel is gliding over the plaster. You have to let it get to a point where it's tightening up before final polishing so just 'slap it on', wait an hour or so and then final polish.

You'll need to wet it when final polishing, flick water on it with a big brush is best.

Make sure you don't go over the edges of the old skim coat or you'll have a bump.

:)

When you've finished, go to the tool shop and buy an industrial Plaster Sanding Machine for the final smoothing ;)

Title: Re: Repairing a skim coat
Post by WOLF on Jan 10^th, 2006, 8:40pm

you for got the 80 plus sheets of grit paper to go with it JD!!

Title: Re: Repairing a skim coat
Post by CWatters on Jan 10^th, 2006, 10:35pm

Thanks folks. Most of what I know I learned from my dad - He could ice a wedding cake and get it really smooth but even he had to admit defeat when it came to plastering a wall. It was the only trade he ever hired as far as I can remember.

Title: Re: Repairing a skim coat
Post by woodsmith on Jan 11^th, 2006, 7:10am

CW if you are going to try this yourself and your skills are less than perfect then an easy method is to;

give it a coat of plaster, shining a light along the wall to show up any ::) irregularities and keeping it below the original surface.

Let that go off fully then,

as it is only a small area,

mix up a box of Polyfilla (don't get the stuff from Screwfix its carρ) and trowel that on.

It goes on a lot easier than multifinish, will feather in to the old plaster easily and sands down without the need for an industrial machine ;)

You should be able to get a perfect finish this way.

There are finishes available in a plastic tub, expensive and the one I tried was absolutely rubbish.

Title: Re: Repairing a skim coat
Post by WOLF on Jan 11^th, 2006, 2:44pm

the only good finish to/for plaster was "AMES" but they no longer do it!!!!! "

>:(grumble-grumble" >:(

Title: Re: Repairing a skim coat
Post by CWatters on Jan 11^th, 2006, 6:40pm

Well the first coat went on and as expected I couldn't get it flat in one go. So I made sure there weren't any high points and will have to resort to filling in the hollows.

I've been working my way around the room removing the old paper and tonight I got to the last wall.... It appears to be something like plasterboard without any plaster on it - just a coat of paint of something similar! I'm beginning to think the previous owner did more of the building work himself than he let on.

It looks like it will be too much work to get the walls suitable for painting so I guess I'll be papering them again. At least I'm good at that.

Title: Re: Repairing a skim coat
Post by WOLF on Jan 11^th, 2006, 8:58pm

ARTEX it!!! LOL hides all the gaps!!!! ;D ;D ;D ;D ;D

Title: Re: Repairing a skim coat
Post by Chaddy on Jan 11^th, 2006, 10:23pm

What about easy fill. sands really easily and you shouldn't have any problems getting a decent finish.

Title: Re: Repairing a skim coat
Post by CWatters on Jan 12^th, 2006, 3:16pm

I think I'll settle for a small thermonuclear device - that should get rid of the problem! I'm only redecorating because I can't put the house on the market in the condition that it in (well I could but it wouldn't be wise).

Title: Re: Repairing a skim coat
Post by Robbo on Jan 15^th, 2006, 3:36pm

Remember to soak the dry plaster skim around the perimiter of the patch as the new plaster will dry out on contact with this as you do your patching and will make it very difficult to "feather" in to the original to leave a seamless finish.

Title: Re: Repairing a skim coat
Post by CWatters on Jan 15^th, 2006, 8:35pm

Thanks for all the pointers. Job done now. Looks OK.