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View Full Version : why do the pommies and the yanks plaster entire wall surfaces?



durwood
11th July 2006, 07:40 PM
Did a search but couldn't see an answer to this question.

In the overseas renovation shows seen mainly on Pay TV both the English and the Americans put up a gyprock type sheet, use a jointing compound and then call in guys to run a thin layer of plaster over the entire surface of walls and ceilings.

You can buy this stuff ready mixed in plastic containers or mix it up and they apply it with a mortor board and a trowel. The pommies even run schools for this so DIY's can learn how to do it.

I can see a nice smooth maybe glossy finish would be a good wall surface to paint but the finish on plaster board is real good also. This would be a hard way to get a top finish unless you had lots of practice.

Anyone have a logical good reason for them doing this extra drying time and lots of extra work especially if you don't get it perfectly flat and smooth.

ozwinner
11th July 2006, 07:46 PM
I have pondered this very question myself, haveing come from Mother England back in 1825, although at my age I useally get some young buck in to do the work.
I just sit in my bath chair and watch, and watch, I could do it for hours.

Al http://www.ubeaut.biz/oldman.gif

rod@plasterbrok
11th July 2006, 09:45 PM
In these countries they only have sheets up to 3.6 m long therefore have lots and lots of butt joins. What they are doing is what we would call a level 5 finish where the entire wall is covered with top coat and sanded back lightly to an even finish.

What this creates is an even surface that reduces the effect of glancing light.

When done correctly you get a great finish.

In the states they don"t do this every where. But it is the standard finish in the UK.

Plasterboard paper face and the join have a different surface under close scrutiny it is easy to pick out a join for this reason. But in some lighting conditions the joins stand out like a beacon. A level 5 finsh gets rid of that.

Cheers Rod Dyson

durwood
11th July 2006, 11:26 PM
Sounds fair enough Rod, thouugh I would have thought that the Pommies would'nt get anywhere as much light there as we do here.

What made me ask the question was in "This Old House" on Monday night they did the walls of the house they are working on and one comment they made was that it was that there was no need to sand the surface off the trowel was so good enough it was ready to paint over.

I can see that the joints would be invisible but a few of the houses I saw in the UK the walls were B##### terrible.

rod@plasterbrok
11th July 2006, 11:33 PM
LOL I agree.

Their sense of quality is not the same as here even though they use a method that SHOULD be better than what we do here.

Solid plaster is not sanded but pollished by flicking water on the wall. But the material being used is softer and requires sanding. It is suprisingly easy to sand a wall that has been fully coated with top coat. Even if it has trowell marks in it. The key is, have high spots rather than low spots.

Its easier to sand off a soft bump than to grind out groove.

Cheers
Rod Dyson

Honorary Bloke
11th July 2006, 11:51 PM
Well, here in the US it is not common practice to coat the entire wall with what we call a "skim coat" of drywall compound, but only the butt joints and screw/nail impressions feathering out about 6 inches. They do it on the TV shows because money is apparently no object.:eek:

That being said, if you, for example, remove wallpaper and want to paint, then you would be likely to "skim coat' the entire wall to smooth out the damage resulting from the wallpaper removal. Sometimes it is easier to just rip out the wall board (gyp board) and replace it complete. I am facing that decision now in my laundry room where the removed wallpaper has left a wall board that is pitted and dinged.:(

Also, for the sake of clarity, you may not know that there is here a significant distinction between using actual plaster and using drywall compound, which is considerably softer, as rod pointed out. It is normal to finish actual plaster without sanding but to sand drywall compound to get it smooth.:)

Guy
12th July 2006, 02:24 AM
the largest avail in the uk is an 8' x 4' sheet, which they generally put on the walls. the ceiling they have small sheets maybe 3' x 2' from memory. I used to work in a builders merchants when i was at college there, also the edges are not bevelled like here but are sqare on all 4 edges, unlike here where the short ends have been cxut as they came off the production line.

bitingmidge
12th July 2006, 10:28 AM
It's all about getting a reasonable finish, I can't answer for US and England however ,here:.

Basically it's not possible to achieve a perfect finish (invisible joints, smooth paint) using standard jointing methods.

Plasterboard manufacturers recommend a light skim coat with their normal topcoat compound (eg CSR Topcoat) to achieve this.

Even with a perfectly smooth and level joint, the joint texture is quite different to the cardboard texture, the topcoat fixes that.

This particularly important if the paint to be used has a level of sheen or gloss, but not necessary at all if it is to be painted.

It is a very rare "house" job in Aus that gets above level 4, most end up round level 3, and painted in a low sheen paint with a bit of texture in the roller.

Cheers,

P

LEVELS OF FINISH.
Levels of finish are defined in the Australian/New Zealand Standard AS/NZS 2589.1: 1997 ‘Gypsum linings in residential and light commercial construction – Application and Finishing.’ Six ‘Levels of Finish’ (0, 1, 2, 3, 4 and 5) are defined, and minimum specifications to achieve each level of finish are detailed in the standard.
It should be noted that, generally, domestic applications should be prepared to a minimum Level 4 finish, and this manual details the requirements for that level.
The level of finish specified affects the methods of jointing, particularly butt joints and back-blocking requirements, the number of coats of joint compound applied as well as the fitting and finishing of stopping and corner/angle accessories.