Exterior wall coatings experience

[u0362565]

Hi all,

We had a company leaflet us about exterior wall coatings. They use Andura coating products. A house down the road has had it done and looks really good freshly done.. Reviews are generally good but how many are written 10 years down the line when it's been there a while.

The Andura coatings seem to be a mixture of acrylic and silicone and some other bits, a lot less water than masonry paint. I guess my concern with these things is two fold. One, our house is 1960's, I think concrete based roughcast, never painted. As I understand this is not breathable and we have filled cavity walls, so in theory already not the best setup. They bang on about how these coatings are breathable but I guess this is less important as the wall wasn't breathing anyway.. Although it could make any damp issues worse I guess. No evidence or history of damp here.

Second thing is that they say it lasts longer than paint. However, when it does need some maintence what do you do? You wouldnt want to keep coating it, so does it have to come off before you start again? I wonder if it causes headaches down the line and it will still get dirty and then can you clean it..

I'm starting to think that a decent paint is better the devil you know. We really want the house white rather than the dull grey it is now so definitely something is going on the render. Re-rendering might be another option non-concrete based but imagine that's £££ and might still need to add colour. Our render doesn't seem to be on bad condition generally. These coatings are mega expensive too, have seem prices between £8-13k including any render repairs and assume that's considerably more than if paint were used.

Would appreciate any experience of these coatings people have?

 

[Ivor Windybottom]

No paint at all would be my preference. Houses aren't meant to be bright and clean. Bare rendering will look better than peeling and/or moss covered paint in a few years. Plus you won't be trapping moisture under it.

Put some photos up if you like, you'll get honest opinions as to whether it would be best left alone or not.

Perhaps coloured render would be the preferred way of dealing with really bad render. If it's in any way bumpy or cracked then any "coating" (paint) will make it look far worse. If it's not brand new then cracks are probably inevitable, even if you haven't noticed them yet.

In fact this photo from Andura's website shows how it highlights the merest imperfections in render...

 

[u0362565]

Thanks for your reply. I agree a dirty painted wall doesn't look great either and I suspect a fairly regular paint coat would be required to keep it looking good. This is partly why they market these coatings as do it once and then don't do again and that they're self cleaning but I've never believed that about anything. Basically other houses in this area have painted or rendered theirs white if possible and it does look nicer in my opinion, cleaner and more modern. Also we're getting grey windows, I know I know some people hate them but combined with a white wall we like the look. But they dont go so well with the roughcast colour hence wanting to change the wall colour. Image attached to show the render colour as is

 

[Ivor Windybottom]

Yeah, I get it. It has repair and insulation scars. The textured finish will look good painted, a lot better than smooth render does.

Light grey would be my choice, give the muck a better chance of hiding.

 

[u0362565]

Yes the colour debate rages on here. Thanks

 

[wallcoatingsbloke]

Hi, I'm in "the trade" but I do not use Andura wall coatings and have no dealings with them, although I understand they "do what they say on the tin" so to speak, I guess its about preference really? A sprayed wall coatings is about 20 times the thickness of normal paint so in most cases yes it does hide imperfections. A wall coating does last much long but only if it is done properly so I guess do some background checks?

A wall coating has many benefits over paint but is up to you what you choose. A rolls Royce is the same as a ford escort, still a metal box with 4 wheels that goes, so it depends what you want. Both normal paint and a wall coating will look good when its done, but the coating will last much longer, it depends on if you want to mess around every couple of years with painters. If the wall is having paint for the 1st time, whatever system you choose will be dramatic for sure. Good luck

 

[u0362565]

Thanks for your insight on this. Andura have been around for a long time which maybe says something. I see what you mean about it physically lasting longer on the wall but if it gets dirty at the same rate as paint then it might depend if you want a clean look or something that's physically intact. Have you gone back to customers to redo a coating and in which case do you cover over the old or hack it off? I wonder how many instances there are of people not being sure what to do with it 10 years down the line when it does need a refresh.

 

[Ivor Windybottom]

I'd be wary of putting a thick coating on an old house. Fine on a new one with a plastic DPC, but I'd be worried about trapping damp on an older one. I know they say it's breathable or whatever but take that with a huge pinch of salt, it probably isn't once it's gobbed on thickly.

It looks like Andura just sells pots of paint. I think it's a product, not a service.

I re-painted our last place. An old 1940 house, with some inevitable dampness. It had been painted in something rubbery feeling, no idea what. But it had peeled and blistered all over the place, it looked a right mess. I just peeled what I could off then overpainted with Dulux Weathershield textured. It looked passable after a few coats. But I don't think the Dulux would ever peel, it just doesn't have that sort of finish. It seemed like it would eventually, after a few decades, possibly wear away but never peel. I think it's bad for a masonry paint to be overly strong, flaking and wearing away is far less of a problem than great sheets of the stuff peeling away.

 

[u0362565]

I'd be wary of putting a thick coating on an old house. Fine on a new one with a plastic DPC, but I'd be worried about trapping damp on an older one. I know they say it's breathable or whatever but take that with a huge pinch of salt, it probably isn't once it's gobbed on thickly.

It looks like Andura just sells pots of paint. I think it's a product, not a service.

I re-painted our last place. An old 1940 house, with some inevitable dampness. It had been painted in something rubbery feeling, no idea what. But it had peeled and blistered all over the place, it looked a right mess. I just peeled what I could off then overpainted with Dulux Weathershield textured. It looked passable after a few coats. But I don't think the Dulux would ever peel, it just doesn't have that sort of finish. It seemed like it would eventually, after a few decades, possibly wear away but never peel. I think it's bad for a masonry paint to be overly strong, flaking and wearing away is far less of a problem than great sheets of the stuff peeling away.

Yes I tend to agree with you on the damp/breathability. Although if we have concrete render then it's not breathing anyway. Yes Andura are the manufacturers but then certain companies take it on and exclusively market it to home owners as a wall renovation service.. They say it can almost act as insulation keeping the home warmer but I haven't found any real data on this. It could be true if it stops the outer wall staying wet and it runs off, a dry wall retains heat far better than a wet one.

 

[Ivor Windybottom]

The insulation story sounds like salesman-speak to me. Presumably they don't actually state this in writing anywhere.

Concrete has some porosity. More than plastic, less than a slice of bread. It's not a simple yes or no. If water can track behind a waterproof coating then it will eventually blister off. If the concrete meets the ground or the bricks it's attached to do then it will have some moisture within it.

I reckon you'd be best off with a few tins of Dulux or Sandtex and a paintbrush. You could always buy one tin, see how much of a job it seems like. If you abandon the idea the super-wonder-coating (paint!) will just go over it.

 

[opps]

(I am a decorator)... I have seen many properties that have the silicone "self cleaning" finishes such a K-rend. Each of them look dirty after 5-10 years. That said, dirt aside, yeah they are largely maintenance free.

 

[^woody^]

(I am a decorator)... I have seen many properties that have the silicone "self cleaning" finishes such a K-rend. Each of them look dirty after 5-10 years. That said, dirt aside, yeah they are largely maintenance free.

The thing is with these coatings, they should be cleaned down every 3-5 years and not just left forever in the hope that they stay clean forever as many building owners do

Once a bit of dirt/soot/algae gets a hold it just expands.

If they are cleaned down regularly (and appropriately for that matter) they do stay clean for the life of the product. albeit that they may get dirtier sooner in between cleans as the surface becomes pitted

 

[^woody^]

Would appreciate any experience of these coatings people have?

They do work as promised. I know of some systems (not sure which, just that they are silicone/acrylic) that have been up for nearly 20 years and are not quite as clean but near enough. These were washed down every 3 years. Likewise, same sort of product on some high rises I know where no washing has been done were dirty and stained after 12 years - different state depending on the direction of the elevations.

You need to do the sums on the cost of the system compared to traditional and paint over say 30 years

Difficult to reach areas would be an ideal place to use these renders as then you have access and risk to factor in.

Breathability is not an issue (and never is) unless you live in a lime mortar old house or suchlike.

 

[Ivor Windybottom]

I don't think the product the OP is looking at is a thick coating like K-Rend, it just looks like tins of paint to me.

 

[opps]

The thing is with these coatings, they should be cleaned down every 3-5 years and not just left forever in the hope that they stay clean forever as many building owners do

Cheers for the input. Unfortunately the people selling these products pitch them as being maintenance free. As you suggested, a wall subject to heavy rain is more likely to stay clean, other walls less so.