render falling off

[mev]

been to look at outside rendering job all the top half of the gable end has fell off needs re rendering its on to thermalite blocks only been done 18 months by a builder. bloke just wants top re doing would it be best to mesh it only prob is i have to match in to existing it is finished in wetdash cheers for any help

 

[pwi]

what has caused it doesnt just fall off the wall > maybe to strong of mix or dodgy roof ???

 

[S a plastering]

probably week mix, or scratch want left to dry out properly

it needs to be a weak mix on thermos mate normally on thermos i scud it aswell cos i hate rendering on them its poo

 

[spark2010]

ya i know it has to be weak. but im saying maybe the mix was wrong, maybe he applied the
topcoat within a few days, who knows,

 

[spunky]

Give it a weak coat of pva and fire a tryolean sbr slurry mix over the top

 

[bubbles65]

And tell punter that you cannot guarantee to match the existing wetdash. It would have to be same source materials, mixed by same lab applied by same spread - everybody's different, so make this point clear.

 

[mev]

cheers for all the replys dont know what the builder did but where it has come off its come of clean none left on blocks at all when you say week mix what strength are you talking thanks

 

[bodplasterer]

We just rendered an extension on thermalites and we were specified 5:1 and 6:1:1 topcoat.

 

[nickelarse]

i woulda said 6-1-1 scratch. bit weaker for top. plenty of waterprofer

 

[spunky]

in the top coat ?

 

[bodplasterer]

We just stuck to the spec sent through from thermalite.

 

[nickelarse]

no waterproofer in scratch.

We just stuck to the spec sent through from thermalite.

yeah i no, just meant what i would normally do. i always thought u needed lime in both coats??

 

[bodplasterer]

Have you ever tried topping a scratch with lime in plus you shouldnt mix waterproofer with lime and you def need waterproofer in your scratch on thermos.

 

[spark2010]

no lime in the scratch just use feb/waterproofer as it reacts

then u can use lime in the top coat not need to use waterproofer

 

[nickelarse]

Have you ever tried topping a scratch with lime in plus you shouldnt mix waterproofer with lime and you def need waterproofer in your scratch on thermos.

i have yeah...didnt have a problem

whats this about no waterproofer with lime?

iv always done that :-\

premixed renders ie cpi etc contain lime and waterproofer?

i did mean waterproofer in scratch, spunky said "in the top coat?" i said no, waterproofer in the scratch... wasnt very clear i no

and as its got me thinking, iv just looked at the spec for a church im rendering in peckham, and it says 4-1-0.5 for scratch coat. on concrete blocks tho...

 

[oasis]

i scratched with lime and waterproofer in the other day wots the problems with that?

 

[Gibbo]

you shouldnt mix lime and waterproofer and cpi has no lime in it

 

[richardbrown]

cpi does have lime in it !

 

[church]

so does cement

 

[spunky]

so does my bottle of corona yummy

 

[McPlaster]

You're all telling the truth.

 

[church]

so does my bottle of corona yummy

Posh boy

 

[spunky]

alright stella then :-[

 

[church]

chav

 

[Pug]

nothing wrong wit a drop of wife beater, in fact i'm on my second tin now. grrr

 

[church]

SECOND my arse i thought you were a spread ??? its Saturday G** boy

 

[spunky]

i was thinking that ;D......i did 6 cans in on the way home and didnt kill anyone 8)

 

[flynnyman]

i was thinking that ;D......i did 6 cans in on the way home and didnt kill anyone 8)

well unless you were driving the bus there wasnt much chance of that happenin

 

[Pug]

sorry boss, i'll try harder tomorrow....

 

[church]

lol

 

[spunky]

plus 6 ounces of weed mind

 

[Pug]

well thats breakfast sorted then!

 

[church]

kids today :