Exterior pebbledash painting - Advise required please

[ripperuk]

Hi guys,

I would like to paint the exterior of my semi-detached house which is pebbledashed.

Please bear in mind that the exterior walls of the house are reasonably exposed to the weather.

Could you please give me any advice on how to paint pebbledash and if there is any way of protecting it, such as waterproofing or if you think this is not required, then please say so.

I'd appreciate any names of products too.

 

[misterhelpful]

Is it pebbledash, roughcast or spar?

Either way, all you need to paint it is masonry paint, a good quality masonry roller and brush. If it has already been painted, the hardest job has been done. If not, prepare yourself for tedium and an aching arm, especially if it's spar.

If it is extremely exposed to bad weather, you will need to use a good quality masonry paint such as Johnstone's Stormshield, otherwise, most quality brand masonry paints will be fine - Sandtex, Weathershield, etc. You may choose a pliolite masonry paint rather than water/acrylic, which should last longer and stay somewhat cleaner - Johnstone's Stormshield Pliolite would be my pick.

The most important part is the preparation. Exposed areas tend to get dirty or covered in green mould/algae/lichen so you may need to clean the walls first. Use a fungicidal wash or diluted bleach solution to kill any mould/fungi spores if necessary and rinse well. For dirt only, use soapy water and again rinse well. Allow all surfaces to fully dry before painting.
If you have unpainted spar, you will find that you will get a lot of the chips falling off as you wash it/apply paint, so brush it all with a stiff nylon bristled sweeping brush before painting. Avoid wire brushes as particles of the wire can get stuck on the wall surface and will begin to rust, leaving you with rust spots bleeding through the finished paint job.

If the 'dashing is unpainted, you will need to dilute your first coat to help ease application - follow manufacturer's instructions but I'd recommend diluting slightly more than they suggest as a first coat on bare 'dash. You will find out which application method is best once you start - sometimes even the best thick pile masonry roller sleeve won't get into all the nooks and crannies, so you will have to use a combination of roller and brush to get the best overall coverage.

 

[ripperuk]

Is it pebbledash, roughcast or spar?

Either way, all you need to paint it is masonry paint, a good quality masonry roller and brush. If it has already been painted, the hardest job has been done. If not, prepare yourself for tedium and an aching arm, especially if it's spar.

If it is extremely exposed to bad weather, you will need to use a good quality masonry paint such as Johnstone's Stormshield, otherwise, most quality brand masonry paints will be fine - Sandtex, Weathershield, etc. You may choose a pliolite masonry paint rather than water/acrylic, which should last longer and stay somewhat cleaner - Johnstone's Stormshield Pliolite would be my pick.

The most important part is the preparation. Exposed areas tend to get dirty or covered in green mould/algae/lichen so you may need to clean the walls first. Use a fungicidal wash or diluted bleach solution to kill any mould/fungi spores if necessary and rinse well. For dirt only, use soapy water and again rinse well. Allow all surfaces to fully dry before painting.
If you have unpainted spar, you will find that you will get a lot of the chips falling off as you wash it/apply paint, so brush it all with a stiff nylon bristled sweeping brush before painting. Avoid wire brushes as particles of the wire can get stuck on the wall surface and will begin to rust, leaving you with rust spots bleeding through the finished paint job.

If the 'dashing is unpainted, you will need to dilute your first coat to help ease application - follow manufacturer's instructions but I'd recommend diluting slightly more than they suggest as a first coat on bare 'dash. You will find out which application method is best once you start - sometimes even the best thick pile masonry roller sleeve won't get into all the nooks and crannies, so you will have to use a combination of roller and brush to get the best overall coverage.

Thank you for your help misterhelpful,.

That's excellent advise and very helpful.

It's not in extremely exposed weather, but the exterior front and side walls get more rainfall than the rear one, so it's kind of got more wear and tear.
I do apologise, but I don't know the difference between pebbledash, roughcast or spar, so I'd need to get this clarified, so that I can try to follow your instructions to the dot.
Could u maybe show me some links, so that I compare to see which one is mine?

 

[misterhelpful]

Pebbledash is traditionally a wall that has been rendered and had tiny smooth stones (pebbles) thrown at it, which stick to the surface.
Spar is effectively a more modern equivalent, but uses various colours of jagged stone chips thrown at the render (Canterbury Spar is probably the most common - pinkish red and white.)

Both of those methods will have 'loose' chippings that fall off the wall over time, spar seemingly the worst and hardest to paint.

Roughcast is a cement based render which can contain chippings and is applied directly to the wall or can be just a cement render that is 'spattered' over the wall with something like a Tyrolean gun.

This is usually a little easier to paint because particles don't fall from the surface, although, depending on how coarsely it has been applied, can still be a nightmare to paint.

Here are a couple of links:

https://www.homebuilding.co.uk/render-faqs/

http://www.telegraph.co.uk/finance/...13/All-you-need-to-know-about-pebbledash.html

Some people like to use a waterproofer/waterseal product before painting but, in theory, a wall finished with either spar or pebbledash should be watertight anyway. Roughcast should also be water resistant, but in most cases is meant to be painted, meaning the paint will add a further water resistant barrier.

 

[ripperuk]

Thank you.

I've taken some photos of the wall, although it was very dark, but I hope this can help you work out which one I have.

 

[misterhelpful]

It's a form of sparring so you can paint it directly. As mentioned previously, clean/prepare the surface and use a diluted first coat of masonry paint. then you will need to apply a minimum of one further undiluted coat, preferably two.

You look to be lucky as the chips seem well embedded - presumably it's a good few years old and the majority of the loose spar has already fallen off.

Good luck.

 

[ripperuk]

From comparing the photos, I thought it looked more like roughcast...no???. The house was like this when I moved in, so I can only assume that it's been rendered when it was originally built, which was the mid 30's.

The chips have come off quite a bit as there are loads scattered on the ground.

Thank you again

 

[misterhelpful]

The chips have come off quite a bit as there are loads scattered on the ground.

This suggests spar as roughcast chippings are mixed into the render before application, meaning they shouldn't fall off. I've always classed what you have as sparring, although various regions may use different terminology for the same thing. The term 'pebbledash' is commonly used by most people to cover all forms of dash, spar and roughcast.

Either way, the painting process will be the same.

 

[ripperuk]

Well that's very informative misterhelpful. This should be sufficient to allow me to crack on now.

Thank you again for your advice.

Much appreciated.

 

[Chri5]

Use a sealer pre painting, some you can spray on.

The paint won't bond the loose stone, and brush painting will pull more dashing off. The sealer will also help the paint stick better.

 

[ripperuk]

Thank Chri5 - May I ask what make brand/type do I get?

 

[richardrich79]

I've used https://www.kingfisheruk.com/section_masonry-paint Weatherflex and found it to stand up to our Welsh weather really well. I painted the rear of our 4 bed terrace which has pebble-dash that looks just like yours. I used a masonary brush to get into all the nooks and crannies.

 

[ripperuk]

I've used https://www.kingfisheruk.com/section_masonry-paint Weatherflex and found it to stand up to our Welsh weather really well. I painted the rear of our 4 bed terrace which has pebble-dash that looks just like yours. I used a masonary brush to get into all the nooks and crannies.

Thanks richard. Did you have to put the sealer on too or did you just put the weatherflex paint straight on???

 

[misterhelpful]

I really wouldn't suggest a sealer unless the surface is powdery, in which case a masonry stabilising solution can be used. Products like Water Seal can act as a water resistant barrier if you wish to leave the surface unpainted but you have to be careful when painting over those products as they can sometimes reject paint, especially if they haven't been allowed to dry thoroughly (with some, that can be several weeks).

 

[motorbiking]

When I painted my house, I bought a paint sprayer as it was a nightmare doing it with a brush