Can A Diluted Solution Of PVA Be Sprayed ?

[WhiteVanJack]

Hi,

Is it possible to use a sprayer with a 5:1 or a 3:1 dilution of PVA universal bond and if so, what type of sprayer is required, ie, 5 parts water to 1 part PVA?

Rgds
Jack

 

[JohnD]

for what purpose?

I am alarmed that this is a "decorating and painting" question

 

[WhiteVanJack]

JohnD,

I intend to paint an unpainted pebbledash gable end with Weathershield masonry paint and was informed that prior to painting a coat of a 5:1 or a 3:1 dilution of PVA would prevent the paint finish from "crying".

The "crying" refers to very small particles of iron ore from the pebbles leaching through the paint finish and causing a streak down the wall. The logic is that a coating of diluted PVA before painting will prevent this occurring.

Do you consider this a "painting" question?

Rgds
Jack

 

[joe-90]

PVA and paint usually lead to the home owner crying.

Listen to JohnD - he's the Daddy.

PVA won't stop bleed through. You need a stabilising solution.

 

[JohnD]

Paint does not stick to PVA, that's why I was alarmed.

 

[Richard C]

DO NOT USE PVA

 

[WhiteVanJack]

Perhaps I am getting confused here, is Unibond and PVA the same to all intents and purposes? If not, does paint adhere to Unibond?

To go back to the original issue, I have unpainted pea shell pebble dash with the probability of trace amounts of iron ore in it that could cause "crying" when painted. What is the process to get this painted with Dulux Trade Weathershield smooth masonry paint?

I thought that stabiliser was to firm up the render/pebbles to prevent it flaking and crumbling. I was not aware that stabiliser acted as a sealing barrier thereby preventing iron ore bleedthrough.

Is a 1:1:1 mixture of Unibond or PVAaint:Water any good as a 1st coat to soak into the unpainted pebble dash followed by 2 coats of paint?


Rgds
Jack

 

[JohnD]

Unibond is a branded PVA

For Weathershield on bare render, I would normally prepare the surface using mist coat of Weathershield diluted with water (per instructions on the tub). Two mist coats if it seems very hungry. You will know when the suction is killed as it no longer sucks your brush dry. I don't know about this iron oxide problem.

try http://www.dulux.co.uk/advice/questions/index.jsp

 

[joe-90]

Stabilising solution is resin based - hence will not reconstitute with the water in the paint. Paint sticks to it. It forms a waterproof barrier.

 

[JohnD]

I once tried spaying stabilising solution on a loose-surfaced chimney in a loft. I diluted it with white spirit to the correct consistency but it wasn't successful and I didn't get good coverage

Outdoors you'd also get it blowing about

 

[WhiteVanJack]

I don't know about this iron oxide problem...

The issue of trace amounts of iron ore "crying" into the paint finish on pea shell pebbledash was pointed out to me by the tradesman who patched the "blown" areas of pebbledash on the wall. This was a tradesman who has 40 years experience working with the stuff.

The iron ore issue is resolved by applying a sealing barrier to prevent the bleedthrough hence my questions about the PVA solutions. I know that the wall is going to be prone to this bleedthrough and I wish to take steps to prevent it before painting.


Rgds
Jack

 

[JohnD]

yes, but I meant I don't know about it so I have no suggestions on Iron Oxide. I bet Dulux have, though.

 

[joe-90]

I once tried spaying stabilising solution on a loose-surfaced chimney in a loft. I diluted it with white spirit to the correct consistency but it wasn't successful and I didn't get good coverage

Outdoors you'd also get it blowing about

You roller it on.

 

[joe-90]

Or if you prefer - use an oil based masonry paint.

 

[Robbie uk]

As Joe says use oil based, Dulux All Seasons masonry paint is pliolite based and will stop any stains or rust appearing through the fresh paint. It also dries in 15 minutes.