backing plaster

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steve

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whats the best backing plaster to use when plaster on bricks, i used browing yesterday in the garage, but wasnt keen on it, its probs the first time thing when youve never done it before. whats the one coat plaster like?, im just experimenting things at the moment

any tips and advice appreciated
 
i use bonding ...seems to me to be strong ..but goes of fast and can reck all ur tools and buckets..need a good lab...hardwall people use but i find it to soft ..i guess the best stuff is sand and cement but its harder to work with and u end up waitin around ages to rub it up...
im still learning my self with backing
 
id say hardwall if you aint got a mixer cos its nice and light, mix in a bath, but you need to be bloody quick...
if you got a kenwood i use sand and cement, waterproofer/plastisiser 3:1 maybe 4:1, bit more work, need 1/2 ton of sand 8 bags opc and a groundsheet.
get the labourer to mix it, take it straight out the barrow, got ages to float it up and it sets like bloody concrete...
well it is, basically :p
matter of preference, its what you get used to i suppose, render can be a bugger if the bricks wont suck, you need to get it on, rule it off and stay off it till u ready to float, dont play with it or you just drag the water to the front and it falls off again...you want the bricks to suck the water in, it dries from the back..
depends on the bricks too, anything hard youre prolly better of with hardwall. Old and softish, like commons should be fine, you need to give em a good brush first too...
if you aint too confident id stick with hardwall...
 
Use hardwall in most situations as you can get the best finish on it, but normally follow this as a rule Bonding on smoother sufaces (usually needs bond-it before application) i.e concrete and plasterboard. Higher suction backgrounds i normally use Toughcoat as it rules of alot easier on surfaces like thermalites or durox (still needs a good soak) also it dont craze crack like hardwall do on these surfaces. Sand and cement on basements or damp proofing (would not recomend using as it shrinks and cracks in random places this process can take upto a year to appear but you can guarentee it will crack), also use sand and cement on bathrooms if they are being tiled just devil float it and you can tile straight onto. Better than sand and cement there is dry-coat or limelite which are basically the same product, use in damp areas or external walls without cavitys it has the same propertys as sand and cement with less shrinkage.
 
ey up bod, never used this toughcoat, whats the difference to hardwall then?
I got a tiny little downstairs loo to do tomorrow, been tiled to the ceiling and the blokes pulled all the tiles off...on board....
Im gonna replace 2 boards cos theres big holes in but the door walls just got all the adhesive still on it..
i told him to stop trying to get the adhesive off before he destroys the place planning to give it a quick thin coat of hardwall then put all the walls on and the ceiling in one set, cant be more than a metre wide, 2 metres deep, small window at the back...
ive given walls like that 3 coats of skim before but i thought id better look like i knew what i was doin..hardwalls gonna be off pretty smartish though...wot u think?
 
id go with bonding mixed with a bita finish will go off quicker and then u can go on it the same day and if u add a small amount of cement will go off v.fast
 
Years ago british gypsum used to make a plaster called H S B browning, which was high suction backing, when they stopped making it tough coat came onto the scene, it sort of acts in the same way you get a little more time on thermalites and dont craze as much you may get a little but no where as bad as hardwall. It also scrapes back alot easier when set i.e around beads and linings. As for using it is almost the same as hardwall a little less sticky and rules off lovely, a few spreads i know use it rather than hardwall all the time.
 
only chargin him 200 quid, wanna be out of there in about 4 hours if poss...
 
yeah the bonding and cement trick is awsome but you gotta be quick had it go off on the spot before i have even got my hawk n trowel out
 
gonna see if i can get some toughcoat, maybe not for tomorrow but i generally like things to go off slowly as normal, then i can always speed it up if need be...its preferable to trying to slow things down if you know what i mean..
made a dirty mix with some hardwall the other day for a quick patch where the backin had blown on an overskim and i was already layin on the finish, labourer spent ages cleaning the bloody bucket...then i was throwin water and pva on the patch as i passed it..not ten minutes..
normally i go straight onto hardwall with the skim, even if its still sticky, it bubbles and pimples like mad but ill let that first coat pull right in before i flatten it an the toppin usually gets it nice..
just gettin a bit nervy with an artex ceiling, bonded wall, only 15 metres but its an awkward little space and the blokes expectin it bang on...not to mention the tile adhesive and bits of board missin...
 
Hi Bigsegs,
Noticed you said you tend to go straight onto hardwall with skim before its set. Heard that this could be done but never had b***s to try it and tend to let backing always dry. Have however gone onto Bonding coat before properly dry but even then whack quick coat of pva before i skim it and still only done this when short on time. Am i missing a trick here? :-? Suppose in theory it is like applying your second coat but always thought backing would interfere with finish or cause bubbling/cracking or something! So you have my full attention ;)
 
hi rocky, well i just got back from that job, heres what i did..
scraped loose off...overboarded the shite boards..
door wall - thin coat of pva cos the wall was shite, just one, pva'd the ceiling while i was at it...
knocked up 1/3 bag hardwall with 3 good handfulls of finish...
troweled it on thin..gave the ceiling another pva
left it 10 mins...
knocked up a bucket of finish..
layed on ceiling, then boards, by that time hardwall was firmish, straight on it with skim
let it pull in a bit, it pimpled a bit, nothin major and flattened it, flattened rest
knocked up again maybe 1/3 of first coat of skim
topped the whole lot
troweled it up
no worries
if you just let the hardwall get firm enough you can stick your skim straight on it...
its just like 3 coating a wall..
to be honest the fastest thing to go off was the board...
you really dont wanna be lettin hardwall go off too much or youll be in trouble..
 
Sounds straight forward enough. Does the adding of finish to hardwall make all the difference then? And how do you gauge this ratio normally? Have you done this with bonding as well if so did you add finish to this mix? Sorry for all questions!
 
not that much really, just 'some finish', bit like a dirty mix, should in theory send it off quicker, seems to work..
if your doin a full wall id just knock up as normal, rule off and float as soon as ready, then straight on with the skim..
i tend not to use hardwall for full walls though..usually render, and skim in the morning...
hardwall for me has become a sort of catch all 'get you out of the s**t' sort of product, i like the sound of the toughcoat bod was on about better though...
 
Cheers matey! Might grow some `dirty mix` nuts and try this out then! ;D Just tend to stick with what you know especially when good finish is required. Although it is great finding new techniques, one of the many perks of the job! ::)
 
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