Paint Won't Stick To Outside Roof Ceiling.

[4.real]

I have a porch and the paint is peeling.I have tried to repaint but the paint [primer and emulsion] will not stick.What sealer should i apply first?

Thanks all for any replies.

I also need to repaint my outside walls.There is a black mould that appears soon after painting.Any suggestions of how to prevent this?

Thanks all once again.

[lopburi3]

Can't really answer but additional information may help others. Is the porch ceiling below a flat cement area that may be letting water seep through? You might have to seal that if it is.

Believe higher quality paint should help the mold problem - have not seen in many years but when had a spray of bleach did help to remove most of it.

[Cuban]

I have a porch and the paint is peeling.I have tried to repaint but the paint [primer and emulsion] will not stick.What sealer should i apply first?

I also need to repaint my outside walls.There is a black mould that appears soon after painting.Any suggestions of how to prevent this?

For the non-sticking paint, ensure the surface is at least brushed down, better if it is sanded to remove all dust and old loose paint. Is the original paint water or oil based? (I also wonder what the porch is made from? Concrete, wood?) Depending on the surface is concrete use a solution of TOA(brand name) PVA adhesive to provide a seal and surface that will take an emulsion paint.

Mould on outside walls, during late afternoon spray with a water bleach solution (use googles) next day wash and brush down. If this is not enough of a cure sand/brush off the paint that is now home to the living mould spoors then prime and repaint with an anti mould paint.

Links to TOA range: Supershield ALL, PENETRATING SEALER HG, Home Page.

HTH.

Edited October 4, 2009 by Cuban

[Thongkorn]

I had the same problem , I got told it depends on wether you paint is oil or water based, And which is already on the walls.

[4.real]

I have a porch and the paint is peeling.I have tried to repaint but the paint [primer and emulsion] will not stick.What sealer should i apply first?

I also need to repaint my outside walls.There is a black mould that appears soon after painting.Any suggestions of how to prevent this?

For the non-sticking paint, ensure the surface is at least brushed down, better if it is sanded to remove all dust and old loose paint. Is the original paint water or oil based? (I also wonder what the porch is made from? Concrete, wood?) Depending on the surface is concrete use a solution of TOA(brand name) PVA adhesive to provide a seal and surface that will take an emulsion paint.

Mould on outside walls, during late afternoon spray with a water bleach solution (use googles) next day wash and brush down. If this is not enough of a cure sand/brush off the paint that is now home to the living mould spoors then prime and repaint with an anti mould paint.

Links to TOA range: Supershield ALL, PENETRATING SEALER HG, Home Page.

HTH.

thanks for the input.

the porch ceiling is ,i believe, ordinary plasterboard.i have tried both emulsion and first oil based primer.Neither will stick to the board.

otside wall is concrete blocks .

[Cuban]

the porch ceiling is ,i believe, ordinary plasterboard.i have tried both emulsion and first oil based primer.Neither will stick to the board. outside wall is concrete blocks.

Ahhhr !

I think you will find that it is not plasterboard (with the humdity in Thailand, mositure would be sucked into the plaster board quickly and result in 'blown' edges and the whole lot will fall apart), without seeing it I would expect that it is was locals call 'Smart Board'. This is made by Chaiyo Industries Co., Ltd. - you will probbaly see their outline of an elephant logo somewhere on the board. This is a compressed conrcrete/fibre product, so treat it like brickwork: brush down, ensure it is dry, prime with masionary sealer, apply top coat of masionary paint. I think I've seen 20 litre plastic buckets for about 1,500 Baht (?). (masionary paint can be water based)

Links: General description. Chaiyo's Smart Board Page.

They offer a 3meg PDF data sheet (with notes on painting) on that site - I have attached below. SmartBoard.pdf

HTH.

[Dave the Dude]

I go with Cuban idea of a mix of watered down PVA glue to seal the area. I have use this method many times in LOS and the UK

Dave

[Cuban]

"...TOA(brand name) PVA adhesive..."

Labelled "Adhesive Latex" Comes in a plastic tub about 400ml for 100(?) Baht or so.

[4.real]

"...TOA(brand name) PVA adhesive..."

Labelled "Adhesive Latex" Comes in a plastic tub about 400ml for 100(?) Baht or so.

Thanks Cuban.I think that will solve the problem