scratch then top coat day after

[Mick Leek]

Hi All,

Hope my old friend JB or maybe legs can help me here.

Is it ok to lay down your scratch coat for external render then lay down your top coat the day after ? or should i leave it a while before laying top coat ?

I was hoping to get the external of my extension finished this weekend..

Also, The rear of my house is rendered down to within 1 meter above the floor level (brick Band) The rear gets about 95% of the bad weather. I have noticed the paint seems to be seperating from the render and flaking off in patches about an inch square. Beneath this is seems very damp although there isnt any apparant dampness inside the house.

Is it possible that somewhere up high around the fascia level, water is getting behind the render or paintwork ? I have also noticed the render is coming away but only under the kitchen window sill..

Cheers in advance

mick

 

[jbonding]

mick its ok to do your top coat on the same day aslong as its not too heavy and the weather is sound. Ive said on here before rendering is not really designed to be painted that is the finish, although there are paints available ie masonry paint, you will find your problem after a few years of overpainting. It sounds like water is getting in somewhere maybe around or under the window.

 

[jbonding]

Its unfortunate that freddie doesnt post on here any more if i remember correctly he had invented waterproof paint that also stops cracks come back freddie im missing you

 

[Mick Leek]

Cheers JB,

Twas funny when you 2 used to have your little lovers tiffs so to speak.... I wonder why he doesn't pay us a visit anymore ? Maybe he has found a new hobby? or better still, got himself a Lady friend

Come on Legs where are you ?

PS

JB Would you add waterproofer to scratch or just top coat ? also what about an adhesion promotor (if there is such a thing) and NO i'm not talking about PVA

 

[jbonding]

I would put it in the scratch maybe a bit of water or rake the joints out also pva mixed with cement and a handfull of sand and applied with a roller

 

[Mick Leek]

JB

Its a new build so VIRGIN concrete block... PVA Really, honest, for outside ?

Thought it doesnt like water ? so what about getting hit with rain in the lovely british climate ?

 

[jbonding]

theres no need to add anything to the block

 

[Mick Leek]

JB,

Just a quick one, i have done 2 walls and scratched, about 10mm. How thick should i do the top coat tomorrow ?

Cheers

Mick

 

[Mick Leek]

JB,

Does it look OK ?

 

[jbonding]

that looks sound mick, the wall looks flat so another 10mm coat should be sound Do that little bit around the corner to get a bit of practice.

 

[Mick Leek]

Was going to do that bit BUT the window fitter said it would be better leaving untill he had fitted the window...

So the top coat is also 10mm then ? I have decided NOT to dash it just have a smooth finish... was planning on doing rest of house smooth as well..

 

[jbonding]

your russian house is similar to the ones we have over here

 

[jbonding]

theres no window on the bit im on about or are you cutting one out?

 

[Mick Leek]

Hi JB

Do you mean this bit ???

Is there any way of removing the salts from the bricks ? It sat that long without a roof before i got around to doing it that it has suffered quite badly

Cheers

Mick

 

[jbonding]

there is stuff on the market for cleaning off the salt, i meant the bit to the left around the corner. Mick im a bit of a perfectionist and if i was you i would straighten that bellcastbead up, the one on the left runs up slightly on the right hand side. Id do it now before the top coat goes on, it might be level but i would follow the brickwork or it will stand out like a sore thumb, even more so now ive mentioned it