Flaking External Walls

[peakpilgrim]

Hi I live in an old house in the countryside; subject to very wet, windy weather. The walls are solid and rendered. some of the external paintwork is peeling off due to previously using cheap paint. I need to stabilize these walls prior to re-painting with 'Dulux Weathershield Masonry Paint'. I had thought of jet-washing all the very loose paint off, allowing the wall to dry and applying a 'Unibond' and water undercoat. Does anyone have any other, better ideas?

[Rich]

Hiya Peak

Depending on the surface of the render, I'd use a wire brush over the entire wall (Get a big one) and get off every last inch of flaky paint first, then wash it down thoroughly with sugar soap, then treat the entire wall to something called "Stabilising solution" which you can find in most decent decorating supply stores.

It goes on like water but looks like really dark apple juice, and is just as sticky too on everything you spill it on.

Brush it on in good doses as you will really want it to soak in as much as possible, hence cleaning the render first to ensure the stabilising solution can soak in and nothing is on the walls preventing it being absorbed.

Leave it for 16/24 hours to dry or whatever the directions state and once dry, it should have an almost shiny glaze to it, and you can then paint straight onto it with the knowledge that the surface is now good to paint on.

Make sure you cover up EVERYTHING that you dont want covered in sticky brown stuff though, if it gets onto window frames its a nightmare to get it off from double glazing and/or painted surfaces..

a 5ltr tin will do a 2bed semi front and side only, so if its totally detached 2 house for example, get 15 litres and put it on good and heavy, you can really go for it with this stuff, even do sensitive areas twice, like around window frames and door frames... Its so runny it soaks into everything.

[peakpilgrim]

Hiya Peak

Depending on the surface of the render, I'd use a wire brush over the entire wall (Get a big one) and get off every last inch of flaky paint first, then wash it down thoroughly with sugar soap, then treat the entire wall to something called "Stabilising solution" which you can find in most decent decorating supply stores.

It goes on like water but looks like really dark apple juice, and is just as sticky too on everything you spill it on.

Brush it on in good doses as you will really want it to soak in as much as possible, hence cleaning the render first to ensure the stabilising solution can soak in and nothing is on the walls preventing it being absorbed.

Leave it for 16/24 hours to dry or whatever the directions state and once dry, it should have an almost shiny glaze to it, and you can then paint straight onto it with the knowledge that the surface is now good to paint on.

Make sure you cover up EVERYTHING that you dont want covered in sticky brown stuff though, if it gets onto window frames its a nightmare to get it off from double glazing and/or painted surfaces..

a 5ltr tin will do a 2bed semi front and side only, so if its totally detached 2 house for example, get 15 litres and put it on good and heavy, you can really go for it with this stuff, even do sensitive areas twice, like around window frames and door frames... Its so runny it soaks into everything.

Hi DIY Guy. Thanks for that info, which is very helpful. Do you have any more information on 'Sugar Soap' and 'Stabilizing Solution' and can you recommend any products?

[Rich]

No, I dont really know enough about that world to know which products are good or bad, but I just went into my local trade supplier and asked him whats the best stuff to use, and took his advice.

[Beaufontboy]

I am with DIY guy here, we have old paint which was pressure washed off, and then treated with sandtex stabilising solution, got it everywhere, it is a night mare to get off ! and then overpainted with sandtex paint, looked good and is still looking good two years down the line,

[Rich]

I am with DIY guy here, we have old paint which was pressure washed off, and then treated with sandtex stabilising solution, got it everywhere, it is a night mare to get off ! and then overpainted with sandtex paint, looked good and is still looking good two years down the line,

Ahhh, thats the stuff... Looks like apple juice when you brush it on and gives the surface a slightly sheen finish that you then paint directly onto... God help you if you splash it on double glazing too, its seriously stubborn, so keep a WET cloth with you the entire time your using it to wipe up spalshes straight away or they will set and never come off.

I painted my house afterwards with sandtex paint and was totally impressed, its great stuff, and the colours are really nice, I used a brown and did the lower 18inches of the walls in chocolate brown, everything from the bell drip down to the floor and it looks great....