DIY Plaster Skimming

[AndrewSchofield]

As you may be aware from my posts elsewhere on the forum, i'm coming towards the end of a DIY loft conversion. I'm completely comfortable with doing the bits no-one will see myself (stud walls, plumbing, insulation etc...) but i'm not insane enough to think i can pick up a trowel and plaster the walls 'as easy as anything'. Therefore i'm getting a plasterer in to do that. However, i'd feel more like i'd acheived something if i at least had a go so i'm determined to skim the plasterboard inside a couple of cupboards that we've built because if it looks rediculous no-one will ever see it anyway.

Anyway, just wondered if anyone can give me any pointers on how to go on?

I'm using Gypsum Multifinish on Wallboard and SoundBloc boards. What volume of MF covers what area? i.e. would 5litres of water mixed up cover 5sq.m?

What sort of thickness/consistancy should my plaster be before i attempt to get it on the walls?

And any other tips?

Or should i just give up now - while i'm ahead!

I'll post a few pics once i'm done so you can all have a laugh!

 

[Alastairreid]

hi andrew, skim coat plastering is easier than you think, mix your finishing plaster to the consistency of angel delight, use a paddle mixer you can get the attachment for your drill for a few quid from any builders merchant.

to start out put about 6" water into your mixing bucket and add the plaster a little at a time till you get the required consistency.
mix only as much as you can use before it starts going off.

as you said pick a small area of wall to start with make sure you skrim tape all the corners and joints use either fine coat corner beads or corner tape for your external corners.
apply the mix at a thickness of between 3 and 5mm.
there isnt any hard rules where you start bottom top or middle as long as you coat the whole area of wall in the one go....... once you have covered the wall you can go back to the begining and start polishing it up after it starts taking up. this will depend on the heat in the room, how big the wall is and your mix.
once you have troweled over wait untill it is nearly setting and sprinkle water on it using a soft brush, and run over it with your trowel to give a nice smooth finish.
it does take practice to get right but i think once you get the hang of it you will end up doing it yourself. saving a fortune to boot. good luck

 

[mattylad]

What I did was, when the plaster was in my house, I sat & watched him.
I first told him how & why & he answered loads of questions.

You can also have a go at your wall the same day so that he is on hand to advise you while your doing it.

If it's not too smooth, once its dry you can always sand it down with a palm sander

 

[Richard C]

Skimming plaster board is certainly easier than float & skim but I don’t agree with Alistair that “it’s easy”; but he could of coarse be a natural. There is a big difference between a perfectly finished wall & something that looks only marginally better than an Artex pattern & you only have to read some of the posts in here to get an idea of how many think they can plaster but really have no idea; but that’s not to say you shouldn’t have a go. Natural ability does have a lot to do with it & you will generally find that you can either do it or you can’t; practice makes perfect of course but some will never be any good. Normally I would advise not to bother “it’ll all end in tears” but I am aware of your project & what your doing so I can understand why you would want to have a go; it is, after all, how I & many others started & lets face it, we all have to start somewhere. Even the very best have gone through it &, you never know you may turn out to be a natural which, to my surprise at the time, I turned out to be!

If you’ve not done it at all before, understand it’s not going to be easy & although a cupboard may initially seem like a good place to start “cos the result won’t generally be seen”, they can actually be quiet difficult due to restricted access & light. Far better idea would be to nail a sheet of PB up somewhere & at practice on that first. You need to have a good idea of the procedures involved; it would be tedious to say the least & almost impossible to explain here & if your serious about having a go, I would advise you watch a video. It won’t turn you into a competent plasterer but it will give you a very god idea of how to go about it; or better still, watch a plasterer you “buy in” &, as Matty says, bombard him with all the questions you can until he tells you to firk off & leave him alone!

To answer your questions; On average a bag of Multi will do around 10 sq/m (at 2mm thickness) but in reality it will be somewhat less using the recommended 2 coats, depending on how thick you lay it on. One bag should easily do you for 5 sq/m though but make sure it’s well “in date” & been stored well this time of year! I generally get all my “bulk buy” plaster products from a B&Q trade centre; it’s stored well & is one of the cheapest places I know. I do use the “local 3” BM’s if I get stuck but they will rip you off given half a chance & their storage conditions can be less than desirable. Unless you have someone mixing for you (unlikely I would think!) you must mix up enough to finish whatever wall your doing. Blending can be done but it’s not the way to learn & for a novice will mean loads & loads of sanding which is not good for the finish. Sanding a newly plastered wall is something that would never be done or be necessary by even a competent plasterer let alone a pro!

Get your self a cheap drill paddle mixer; don’t mess around with bits of wood or spoons, by the time you’ve finished you will have lost 10 minutes on the set time which, you will learn, can make all the difference. Consistency mix is around 11.5 litres of clean water per bag & add the plaster to the water; it should be stiff enough so it doesn’t fall off the hawk/trowel but if you make it too thick it will be a pig to work & go off quicker. After you mix it will initially stiffen a little within 5 minutes after you first mix it so bare that in mind & don’t over mix or it will go off quicker which is the last thing you want. Don’t use water until finishing off & don’t use too much; I use an old 1 litre kitchen spray bottle & I can do an average size room without having to fill it up, if you over water the surface it will turn to mush. You don’t normally PVA PB before skimming but I would advise you do it; it won’t do any harm & will give you a little more time & that’s always your enemy!

 

[roy c]

I personally think that all this worrying about the "plaster setting on you", can put you off a bit. Well dont worry about it if you are practicing on a board. Normally from first coat to final trowelling can be up to 2and a half hours!!! So mix up your "muck" and practice taking it from the hawk to your trowel, you will have to master this before you can do anything with the plaster. When you have mastered that get a bucket trowel and take some out the bucket with it and put it on your hawk, not too much ,I would start from half way up your board (from l/h side if right handed and r/h side if you are left handed.) take the muck off your hawk and hold your trowel at about 30degrees to the wall then put it against the wall and slowly pull it up the wall allowing the muck to spread onto the wall as evenly as poss when you come up about 16-18 inchs from the top turn your trowel off in an arc and pull it off the wall. Do the same again picking up on the r/h or l/h side of the trowel mark(depending what hand you are using).and do this all the way across the wall. Then drop down to the bottom of your first line and do the same and carry your trowel on up to the top and arc off again. Do this all the way across again. this will give you an idea of the laying on process. As you are only practicing I will not go into detail to much about meeting the ceiling and abutting walls, but as you can see there will be a gap at he top and sides so fill the side ones in by putting muck on your trowel and come down from the top dropping down every trowel width and work from the abutting wall out till you get to the bottom then put your trowel on flat again into the corner and pull it up like you did when you first started. Do the same process with the ceiling and fill in. when you have got the wall covered put the kettle on have a cup of tea and clean your tools. After about 10-15 minutes do your first trowelling, start same place in the middle l/h or r/h side and hold your empty hawk in your hand and trowel upto the top and arc off putting any excess muck you drag off on to your hawk. Go all the way across and then start at the bottom and pull your trowel all the way up to the top and go all the way across again.you are now laying the plaster down flattening it out. leave it again and your next trowelling should not leave any marks as you go up and across, if its a bit "Stiff" just wet your trowell with a water brush and carry on. Dont put any water on the wall!!! When it is flattened out and most of the large trowel marks have gone then you can mix up another batch of muck,not too thick and you can lay this on like you did the first coat,then leave it again then trowel it when it picks up abit to flatten it out then wait a bit longer and wet trowel it to a finish... This is the basic technique for skimming a wall but there are a lot of variants that come in to force when actually doing it, I cant mention all these now but if you try not to "play" with it too much, walk away and leave it a while dont throw "loads" of water on the wall,and practice and practice and also time it from starting to mix and final trowelling as you go along you will get the feel for it and your confidence will grow.....Good Luck

 

[Richard C]

I personally think that all this worrying about the "plaster setting on you", can put you off a bit. Well dont worry about it if you are practicing on a board. Normally from first coat to final trowelling can be up to 2and a half hours!!! So mix up your "muck" and practice taking it from the hawk to your trowel, you will have to master this before you can do anything with the plaster. When you have mastered that get a bucket trowel and take some out the bucket with it and put it on your hawk, not too much ,I would start from half way up your board (from l/h side if right handed and r/h side if you are left handed.) take the muck off your hawk and hold your trowel at about 30degrees to the wall then put it against the wall and slowly pull it up the wall allowing the muck to spread onto the wall as evenly as poss when you come up about 16-18 inchs from the top turn your trowel off in an arc and pull it off the wall. Do the same again picking up on the r/h or l/h side of the trowel mark(depending what hand you are using).and do this all the way across the wall. Then drop down to the bottom of your first line and do the same and carry your trowel on up to the top and arc off again. Do this all the way across again. this will give you an idea of the laying on process. As you are only practicing I will not go into detail to much about meeting the ceiling and abutting walls, but as you can see there will be a gap at he top and sides so fill the side ones in by putting muck on your trowel and come down from the top dropping down every trowel width and work from the abutting wall out till you get to the bottom then put your trowel on flat again into the corner and pull it up like you did when you first started. Do the same process with the ceiling and fill in. when you have got the wall covered put the kettle on have a cup of tea and clean your tools. After about 10-15 minutes do your first trowelling, start same place in the middle l/h or r/h side and hold your empty hawk in your hand and trowel upto the top and arc off putting any excess muck you drag off on to your hawk. Go all the way across and then start at the bottom and pull your trowel all the way up to the top and go all the way across again.you are now laying the plaster down flattening it out. leave it again and your next trowelling should not leave any marks as you go up and across, if its a bit "Stiff" just wet your trowell with a water brush and carry on. Dont put any water on the wall!!! When it is flattened out and most of the large trowel marks have gone then you can mix up another batch of muck,not too thick and you can lay this on like you did the first coat,then leave it again then trowel it when it picks up abit to flatten it out then wait a bit longer and wet trowel it to a finish... This is the basic technique for skimming a wall but there are a lot of variants that come in to force when actually doing it, I cant mention all these now but if you try not to "play" with it too much, walk away and leave it a while dont throw "loads" of water on the wall,and practice and practice and also time it from starting to mix and final trowelling as you go along you will get the feel for it and your confidence will grow.....Good Luck

& all I said was watch a film; well done.

 

[roy c]

Trying to teach some one to plaster,(on a Forum) is like trying to tell some one what it is going to be like ,being a parent!!!!!!!

Eh Rich?

 

[Markymilarky]

Hi Doooods,
I dident have a clue about plastering and needed to do my whole house to save money. I read up on it and practiced on a bit of wall to get the hang of things. more often then not loads ended up on the floor till i got the hang of the hawk.
All of downstairs was a learning curve and needed varying degrees of sanding to make it look professional but by the time i got to upstairs i had it sused and it all came out fab. When i started i felt like there was no way i was going to get the hang of it and it was all going to look rubbish. My brother in law has been a plasterer for 20 years and he said upstairs was perfict. so im happy. reckon it's just perseveriance and believe you can get there with it. everyone has to start somewhir. I really dident think i would be any good as it was like i had 2 left hands with poor coordination but it all comes together in the end. give it a go and think positive. all the best mark

 

[bananaspark]

i've tried my hand at many things, but plastering has the toughest learning curve of all - like a cross between a 1hour bout of judo and alternating playing darts/snooker...at the same time.

top tip -leave your phone switched off when you start