Floating over thermalite blockwork

Members online

Status
Not open for further replies.

Arcane

New Member
Hey there,

Due to start a job in a few days which will entail floating over thermalites. Never done this before and heard nothing but BAD things about it.

Another builder has recommended a product called 'Weber.Rend Stipple Coat' that can apparently be used as a backing coat on the thermos to provide a workable key and prevent the 'devil' suction!!

Has anyone used this product for this purpose and, if so, how's the best way to apply it as a backing coat prior to floating the block? :RpS_blink:

Hope someone can give a bit of advice.

Ta...
 
Im floating on the dreaded should be banned blocks on a school at mo. No one will pay any extra for that.im hosing blocks down 5min before floating. And two coat the hardwall.holds off the instant suction
 
Nightmare mate!

Tried to talk some 'dot and dabbing' sense into customer but wont have it. Pesky regs... lol

Anyway.... you hears of that Weber.Rend Stipple before?
 
Same as that, thermalites and turbos are fkin nightmare. I hose the fuk out of them, there's never enough money in the job to warrant some kind of scratch coat.
 
Had to take it on a day rate.... and happy too! Need to be able to have the movement on the job.

So you're saying that Weber.rend stipple is the same as hardwall grump? Trowel on and stipple with an old brush then before floating as usual?
 
I think you are talking about rendaid mate normaly used for prepping certain types of outside walls prior to render just lay it on thin and stipple it with a roller wouldnt use it as a prep for hardwall though to expensive though it would work.
 
Use though coat on thermalites much better if you using hardwall BG say you should prime it first :RpS_thumbup:
 
No it's not hardwall! Like lucius says its a rend aid type product. Put it on tight the hard wall next day. Tis an expensive solution though. Sand cement with proofer or pva or plain old hose for me. As Long as the client don't see mee soaking the joint!
 
No it's not hardwall! Like lucius says its a rend aid type product. Put it on tight the hard wall next day. Tis an expensive solution though. Sand cement with proofer or pva or plain old hose for me. As Long as the client don't see mee soaking the joint!

Hahaha!! I'll be soaking it up and using this sh*t too! Client has already bought the stuff.

Seriously though... using therms on walls that need floating. F*cked up. Regs sucks balls.
 
Or just use gypprime like british gypsum tell you to on high suction backgrounds. Would be much easyer.
 
That GypPrime looks like a solution! Hmmm..... liking the look of that. Can just spread on like PVA then get right onto the trowel. Much better.
 
It's not cheap though but we always price it in now. Think we pay £65 plus vat a tub.
 
Knauf Grundiemittel, which is German for primer ( I think, but Im sure some one on here will correct me !) . We been getting it from B centre at £ 56 per tub, will do 150 to 200 metres ( depending on dilution.) thinks that circa 28p per metre sq.

Just like BG gyprime, the Knauf is very good gear , no need to soak in block work, we floated 20 bags plus before dropping back to devil up and cut out.

Reckon you should pay no more that 60 s for it.
 
Will check it out mark. We seem to be using more and more knauf stuff at the moment. Loving mp75 at the moment and have ordered a pimped up long angled gun off stuart to make it even easier. Two coat seems like twice the work now!
 
Will check it out mark. We seem to be using more and more knauf stuff at the moment. Loving mp75 at the moment and have ordered a pimped up long angled gun off stuart to make it even easier. Two coat seems like twice the work now!

Does the Ritmo throw the MP75 on quick enough to keep a guy going just ruling off Steve?
 
YEP ist just about perfect

Definitely sounds like the perfect machine for you then Steve, must be the most versatile setup out there.

To the opening post.
You don't state what you're floating with (unless I missed it), but if it's sand and cement then Thermalites or Celcons don't need any pre-treatment. Use the box screed method of floating and they're great to work on, by far my favorite types of block to work on.
If using Hardwall I now either give them a light spray from a hose or a quick and I mean quick flick over with a roller of Blue Grit or similar. Not enough to even come close to sealing them just enough to hold the suction enough so the Hardwall doesn't craze and pull away to much. Again use the box screed method.
 
Why? Aren't we just trying to kill some suction here?

Because suction aids adhesion and dry PVA is not the best thing for floating coats to grip to. Most of the aerated blocks now have plain faces and if the joints are neat and tidy there's not a lot of key, which is where the suction is a good thing.
With a quick flick of Blue Grit you just lessen the suction a bit and also have a gritty surface for the Hardwall to get a bite on.
Maybe I just think to much, but that's how I am.
 
Yeah i see what you mean. I normally just roller on a real weak PVA mix, 5:1 or weaker. So to not kill all the suction.
 
I've just remembered something my old man told me. He said years ago when Durox blocks first came out that they were even higher suction than they are now and that a firm he was working for got the rep out to ask the best way to deal with them. The reps answer was to dilute some Fairy liquid into some water and to brush/roller this onto the blocks, which really did hold back the suction. I'm not sure that the block manufacturers would say the same nowadays though.
 
I would just use a piss thin coat of pva and water mixed so its like milk. Still leaves a bit of suction.
 
Not being funny mate but you must be "only" a domestic type spread to do that, you couldn't survive doing that on site/new build work.
Yep your right mate,I am "just"or"only" a domestic spread.if I had to work on site then I would take on board whatever needed to be done for speed purposes.i do well enough to earn a good living working in folks houses,but wouldnt have a problem doing site work if needed.when I can "re-skim"the same meter age as someone workin on pretty new board work,I'm not worried.whatever it takes to pay the bills.domestic spreads get a bad name from a lot of site boys,but I've been on some sites where the work is pony in my view.no offence taken or meant:)
 
Yep your right mate,I am "just"or"only" a domestic spread.if I had to work on site then I would take on board whatever needed to be done for speed purposes.i do well enough to earn a good living working in folks houses,but wouldnt have a problem doing site work if needed.when I can "re-skim"the same meter age as someone workin on pretty new board work,I'm not worried.whatever it takes to pay the bills.domestic spreads get a bad name from a lot of site boys,but I've been on some sites where the work is pony in my view.no offence taken or meant:)

Site work is very repetitive, all new too so not so much skill needed to get a good result.

More knowledge is needed on domestic.
 
site work (commercial work) requires experience and skill to hit the meterage expected to commercial standards, which is scrutinised!!...all work has to be bang on!! or it will not be passed and you will not be getting payed....if a spread has experience in commercial work u know they're standards are to a commercial level which is to british standards simple as that....domestic spreads vary from top experienced spreads to general builders to painters & decorators to just about anyone who calls themself a plasterer..
 
Status
Not open for further replies.
Top