Paint keeps flaking off outside walls of house

Dopey

We paint the outside walls of the house every two years as the paint bubbles and flakes off in that short time. We tried a coat of unibond and bog standard masonary paint the last time. We were told from the previous owner that too much lime was used in the walls.

It's a big job to repaint as we have to powerspray the walls before we paint.

I've heard that the only solution is to replaster the outside walls. Sounds over the top to me.

Any tips on getting around this?

Yours truly,

Dopey

Borzoi

Dopey wrote:

We paint the outside walls of the house every two years as the paint bubbles and flakes off in that short time.

Scrap off the loose flakes with a wire brush and coat with Alkali Resistant Primer - it's available in most specialist paint shops, not cheap stuff but it should do the job.

Dopey

Thanks for taking the time to respond Borzoi.

How does the primer work?

The previous owner may have been spinning me a yarn about the lime. If the lime is the cause what does the primer do? Prevent it from interfering with the paint?

Apologies for all the questions. I am a man of few answers but many questions!

Dopey

Borzoi

Dopey wrote:

Thanks for taking the time to respond Borzoi.

No problem

Dopey wrote:

How does the primer work?

The previous owner may have been spinning me a yarn about the lime. If the lime is the cause what does the primer do? Prevent it from interfering with the paint?

Eh? ask me a sports one! Honestly I don't really know but: Old paints were sometimes just a lime wash, lime is an alkali material, the Alkali Resistant Primer, seals in the lime wash, allowing your new paint to go on, and stay on. Or at least that's my understanding.

I've used the ARP before several times, and it is the business. I've seen the lime come through decades after it was first applied - don't know why, and the ARP has solved it.

Obviously I can't garauntee it, but you could always try a test section on a low wall.

Dopey

Sounds good to me. I'll give it a lash.

If it works the neighbours might stop calling me the village idiot. :cool:

Cheers,

Dopey

mad m

Well the Alkaline in the plaster breaks down the oils/resins in paint over a time but this was only the case if you applied oil based paints over plaster or concrete not Emulsion,hence Alkaline restistant.I was told only ever to apply Alkaline resistant paint over plaster/render before oils based finishes are applied.Is the bubbles in patches or all over the whole area of house?

It could be nothing to do with lime,maybe the render on your house needs stablising.There is a primer called Stablising Solution,this can be great to seal porus surfaces before applying 100% Acrylic Emulsion e.g(Weather Shield).

When i started serving my time everything was oil based paints and these were great in their own right,but days have come where Eco friendly paints are taking over from oil based paints.

check out link below.

here


I think you can get this from any major places,which if you are from dublin go to Davitt road and Dulux&Fleetwood are there.

mad m

Just to add what Borzoi was saying,Borzoi is right also this could solve your problem.I've come to learn that Theory&Practical dont always go hand in hand.Either of those method should solve the problem...