question about bonding/browning

[squowse]

my labourer is quite handy at plastering but his knowledge is slightly limited, so although i have learnt a lot from him i have a question about the types of plaster.
we did a stud wall that ran onto blockwork, there was a slight kink in the line of it (existing studs) and the blockwork was a little bit rough (my work, ahem), he put on what he was used to using - PVA then 10mm bonding to bring it up to the same level as the adjacant plasterboard. we had to let it dry overnight as it was late in the day. then two coats of multi-finish over the whole thing.

my question is - would we have been better off using browning without pva, and would it have dried quicker with the suction. or would it have cracked as too thick? i got him the bonding as he's never used browning before and wasn't sure about it. but now we're waiting to paint and i was just wondering if there was a quicker way next time.

 

[Alastairreid]

Why pva over new blockwork, plasterboard?.

i would just bond the lot then skim over.

 

[squowse]

Why pva over new blockwork, plasterboard?.

i would just bond the lot then skim over.

by just bond do you mean use bonding plaster? that's what we did.
if you mean bond with pva then skim directly, like i said there was a kink in the wall that required filling, also the blockwork was a little rough, also there was the broken edge of a brick wall that also needed filling.
could have dot and dabbed, but wanted something a little more solid for shelf fixings.

i was asking the difference in use and characteristics of bonding and browning.

 

[Alastairreid]

by just bond do you mean use bonding plaster?

.

Yes but i dont use pva glue!.

i was asking the difference in use and characteristics of bonding and browning.

.

not a lot browning is generally used in less porous subtrates ie engineering brick.
also with a maximum applicable thickness of approx 10mm as opposed to 8mm with bonding plaster.
browning is also a lot more porous and lighter to work with.
generally bonding plaster is the better of the two.

 

[dave1953]

Hi, I've used Hardwall on numerous occasions and it lends itself to a variety of substrates without Pva

 

[squowse]

Hi, I've used Hardwall on numerous occasions and it lends itself to a variety of substrates without Pva

ok, what is the max thickness and how fast does it dry compared to the bonding? i am wondering if the suction without pva helps it dry.

the bonding plaster bag recommends sealing porous substrates such as brick with pva. not sure about concrete block.

 

[Alastairreid]

www.british-gypsum.com/products/thi...stle_undercoat_plasters/thistle_hardwall.aspx - 30k

dont know the price of this gear though.

 

[dave1953]

sorry for delay, Hardwall costs less than bonding i.e about £4.80 to £5.10 where I am in Dorset. Bulk buy is cheaper. It sets quickly dependant upon mix ratio and is very controllable, if substrate is very dry I always wet it to slow down the setting time, i.e.Thermalite blocks etc. your concrete blockwork should be fine without wetting, hope this helps.