Plastering in my extension

[delboybully]

I am having a single story extension built. The builder is making it water tight, the rest i am doing to keep costs down.

I have a plasterer to do the plastering but i want to do as much prep work as possible. I want the plaster to be the base coat and finish type and not the dob and dab plasterboard and skim

The back wall of the existing house is painted, and this needs to be removed before plastering. Whats the best and easiest way to remove this paint, someone told me you can get a bit for an SDS drill to do the job. Does anyone know what this tool is called

Also the radiator heating pipes shall be covered by the plaster. I am guessing these need to have some sort of cover over them or the constant heating/cooling of the plaster from the heating pipes will cause some problems. What the best covering to use?

 

[marshman]

Hire a needle gun to remove paint.
your pipes will need to be chopped into the brickwork then covered with pipe insulation, then eml expanding mesh fix over the pipe channels.

 

[Micilin]

Make sure your plasterer is happy with what you are doing before you start anything.

Be careful about bashing the hell out of your existing walls though.

You can get a needle gun as the marsh man says .

For the SDS drill, a 'Bush Hammer' is what you are looking for. It's a disc/square/hex on the end of the shaft, with indentations/points on it.

Like these

http://www.chisels-and-bits.com/bush_tools.html

 

[keyplayer]

The back wall of the existing house is painted, and this needs to be removed before plastering.

Does it? Maybe not.

 

[Richard C]

The back wall of the existing house is painted, and this needs to be removed before plastering.

Does it? Maybe not.

Rather depends on what it's painted with; but is probably the best route to take given that the OP wants a base coat & skim.

Just to reiterate what Micilin has said; don’t go doing any prep unless your plasterer is happy with you doing so & then follow their instructions to the letter. Doing your own prep may seem like a good idea to save cash but in reality you won’t save much if anything & many, including myself, won’t agree to it as it's the only way I can guarantee the quality of my work. If I do the prep & it goes wrong, it can only be my fault; if you do the prep & it goes wrong, who’s fault do you think it will be then!

 

[keyplayer]

Rather depends on what it's painted with; but is probably the best route to take given that the OP wants a base coat & skim.

Ah yes, my mistake. I assumed the wall in question was already rendered and just needed skimming, but a reread suggests that it is directly painted brick/block work. You wouldn't want the paint holding up the weight of a float and set.

 

[delboybully]

The plasterer is happy for me to do the prep work and he is going to check it is ok before he will start. In fact to keep costs down he is happy for me to be his labourer. I shall be helping him to put the plaster board on the ceiling and also to help with mixing plaster etc

Hire a needle gun to remove paint.
your pipes will need to be chopped into the brickwork then covered with pipe insulation, then eml expanding mesh fix over the pipe channels.

Do the heating pipes need to be chased into the walls. The walls are bare and will be covered in base coat and finish plaster. Cant they just be covered and plastered over

 

[Richard C]

Yes you need to chase the pipes in as total depth of plaster will only be around 12-16mm thick & this won’t be enough to cover the pipes. & don’t just plaster over the top of them either or expansion & contraction in the pipes will crack the plaster. Wrap the pipes & cover with either mesh or, as I do, steel or plastic cable capping, this allows them to move/expand/contract behind the capping without affecting the plaster.

 

[delboybully]

ok thanks for all the info, it is very appreciated.

The wall with the paint on has a patio door (to be removed and become an open walkway between the extension and the old living room) and will have double doors to the dining room so the wall space is not that much. It will also have heating pipes coming down and going into the floor. Given the information you have all given i have decided to batten and plaster board it followed by a skim coat

The feeds to the 2 rads (different walls and in copper pipe) come up from the floor to the rads. I shall chase these into the wall and then cover them in some black plasticy stuff (cant remember the name of it) that the plumbers merchants recommended. The plumbers merchants also said to cement in these pipes and then to place expanding metal across the 'gap' and then plaster with the base coat and skim over the top. Does this sound right. My thoughts are that cementing in the pipes in the chased bit would be unnecessary, what do you all think

 

[Richard C]

The plumbers merchants also said to cement in these pipes and then to place expanding metal across the 'gap' and then plaster with the base coat and skim over the top. Does this sound right. My thoughts are that cementing in the pipes in the chased bit would be unnecessary, what do you all think

No I wouldn’t do it like that either. I keep the width of the chase to the minimum needed to accommodate the pipe & the size of steel capping I’m going to use over the top. If the pipe needs additional support, I fix it with flat copper pipe straps (not plastic fittings) as required. I wedge the cable capping over the pipes into the chase & use plasterboard nails down the edge of the capping to hold it in place as required. I prefer steel rather than plastic capping as you can bend it to suit the width of the chase to get a snug fit. You can put some expanding mesh over the capping if you wish but I don’t usually bother. I fill out the chase flush with Bonding or render (depending on the base I’m using) & put several overlapping layers of reinforcing tape over the chase before base coating the lot.

 

[delboybully]

Ok so i keep the chase to a minimum. thats the easy part. What is steel capping, is this the same as the expanding metal?

Is the reinforced tape the same as skrim tape (the criss cross tape that you put across plasterboard joins).

Could you give me some links so that i can see what i need please. Sorry for being a pain

 

[Richard C]

What is steel capping, is this the same as the expanding metal?

No; steel capping;
http://www.discount-electrical.co.u...nised-steel-capping-25mm---1-inch-x-2m-length
Comes in various widths, easiest place for you to get it will be B&Q.

Is the reinforced tape the same as skrim tape (the criss cross tape that you put across plasterboard joins).

Yes, fibreglass scrim tape;
http://www.diy.com/diy/jsp/bq/nav.j...refview=search&ts=1293097687920&isSearch=true
You can also get this in B&Q

 

[joe-90]

Can't see why anyone would try to remove well-adhered paint. An SBR slurry would be better. If the paint is flaking then some kind of wire brush/scraper prior to SBR slurry is the way to go. I sometimes wonder if you guys live in the real world.

 

[delboybully]

The paint isnt well adhered, it will come with some scraping/ chisleing but not easily

The reason i wanted the paint off is because i wanted the plastering in my extension to be the same as the rest of the house (1950 ex council house). I also prefer the bonding and skim coat to plaster board and skim

Having said that, i am going with battens and plasteboard and skim coat on the painted wall (the others will be base and skim coat)as i think the hassle of removing the paint and chasing 4 heating pipes in the wall isnt worth the hassle. THe other walls with heating pipes will be chased in the wall

 

[roughcaster]

You'll always get a much better finish with bonding and multi, rather than just a thin skim finish coat.

Some skim coats are that thin, you can actually see the tapes,, and a distinct line shows through at every joint in the boards. I probably use more butter on my sandwiches, than some skimmers use plaster on a whole wall.