UKC

My house is pebbledashed and I want to replace the pebbledash completely.

Is there any reason why I shouldn't replace pebbledash with smooth render?

Only the top half is pebbledashed and the brickwork in the bottom half doesn't look great and certainly needs repointing. Any reason why I shouldn't render over this bottom half at the same time instead of just repointing?

What are the pros and cons of coloured render that you don't have to paint?

cheers

Also looking at this as it seems to be the new fashion, loads around us are having it done, but when you look at the 5 year old smooth render it seems to get discoloured and see loads of skimmed render failing where pebbledash seems to be as tough as old boots mine is coming up to 100 years old and good as new.

Some of the smooth render finishes on my road are growing moss and are discoloured. But then so is my pebbledash!

Have you thought about cladding it?

I had a couple of walls done with Webber render about two years ago. No problems as yet.

I had mine removed and smooth lime render applied. looks lovely and far better for the timber framed building as it can now breath. If it was just for aesthetics then I might not have bothered considering the cost though.

How was the removal?

Considering stripping my pebbledash before applying breathable external insulation. Looks like a truly horrible job.

Having said that I have no damp problems with the existing, presumably 100% non-breathable, pebbledash so I wonder if it's necessary.

Decisions decisions... 

I once got myself a tower scaffold and a jack hammer. I can assure you that getting pebble dash off is a murderous job, especially if it has been put on properly.  Upside was I had hands like steel claws and got a lot of good solos in. 

I think it’s meant to hide areas of the render that’s not straight, however, I bought a 200year old Cob house, and love the smooth render because it’s not straight! 
 

I think smooth looks very nice but that’s only my opinion 

cheers

I once lived in the middle of a long terraced row. Mine was the only stone clad one. It was brilliant when stumbling back from the pub, or giving people directions Happy days!

You are Jack Duckworth and I claim my £5

My understanding is that pebbledash while not pretty is super effective at keeping weather out and lasts longer than everything else. Also keeps damp out better than others as all little pointy bits shed water away from wall. 

Nope, it was in Coventry, not Weatherfield. You haven't Scooby-Doo unmasked me this time!

The big danger is that in removing the PD, you will absolutely wreck the brickwork underneath. It'll pull half the brick faces off and wreck the joints. 

If you're set on removing the PD, have you thought about just having the bricks instead of rendering? Rending isn't great for the house really. Stops it breathing. 

Thanks, good point. I seem to recall now that rain bounces off pebbledash and away from the house whereas it just runs down smooth render

I think pebbledash and render are generally used when the brickwork is naff anyway. That's certainly the case with my house. So I will definitely be removing the old pebbledash it's just a question of what to put back in its place. I might be wrong but I don't think either render or pebbledash are completely airtight and are better for the house than having exposed substandard brickwork

Correct, and also because it has a much bigger surface area it increases the rate of evaporation of moisture from the wall surface.

not exclusively, all renders are there because brickwork is inherently not watertight and lets moisture through. single skin walls would be rendered regardless of brick quality.

in the past, anything >30 odd years ago, there were small local brickworks all across the the country - and quality varied equally. nowadays, just like your supermarket bread, everything is made in one of only a handful of big manufacturing plants. (and it's all the fricking same regardless of brand name)

personally view: if you do go down the route of "smooth" render (there are options within smooth) - I'd be sure to ask your contractor to give examples or previous jobs they have done and go and visit them.

At least 15 years ago I had failing parts of our pebbledash replaced at the front of our house but decided to replace it with smooth render on the side. Single skin bick wall, no cavity. I specified waterproofer mixed with the render and the pebbledash base which is then apparently still breathable. I put a new (probably second) coat of masonry paint over the pebbledash but left the side unpainted. No problems with damp so far but unpainted side has a long crack (movement) and discolouration due to drip from combi boiler when windy....if I wanted to hide these I'd probably fill crack then paint the side.

Building regs approval required.

Building regs vary with exposure rating. Some places need render if some sort to make morter/brick work weather proof. 

Agreed, although if it's going to be covered up with new render or cladding that's not a problem.

Brick walls are inherently not watertight - the shrinkage rate of cement mortar is such that the vertical 'perps' between the bricks will always come away from at least one brick, leaving a vertical crack for the wind to force rain into and blowing air through the cavity increasing heat loss.  A 'modern' house with DPCs and cavity walls doesn't need to breathe - it won't be soaking moisture up from the ground, and penetrating rain runs down the inside of the cavity leaving the inner leaf dry.  It's better to stop the outer leaf of bricks absorbing water in the first place and turning the house into an evaporation fridge.

So is your understanding that pebbledash is breathable?

I thought that, being (usually) cement based, it wasn't? 

We were also thinking of replacing our pebbledash. We were keen to go the modern, smooth render route as those houses in the street that have been done looked great. But now some have been done five years, I've noticed there's large areas of discolouration and even south and west aspects are covered in mould and mildew. One guy has actually painted his new render with masonry paint to 'freshen' it up which he says wasn't too much bother. What?! Every five years? Traditional pebbledash is back in favour again in our house.

I am no expert. However I'm pretty sure that render and pebbledash should be and generally are breathable. People often paint over it and although the masonry paints that I've used (usually Dulux Weathershield)) state they are breathable I think its recognized that this will be less so if other coats are added. I've  often used a stabiliser before painting and its hard to imagine that that doesn't reduce breathability. We don't seem to have damp problems due to this ourselves.

Incidentally a well applied coat of masonry paint seems to last a long time unlike paint on timber, perhaps expansion and contraction  of wood have a deleterious effect. Any knowledgeable decorators out there?

Modern exterior emulsion paint doesn't seem to stop algae growing at all.  I'm wondering if sol-silicate stuff (like Keim paint) is better in that respect.

Got K-Redner on the back of my house and it looks very good. Strangely satisfying scratching it smooth too. It's not lost it's brilliant white yet, seems  to come good just with a little pressure wash every now and then. 

https://www.k-rend.co.uk/

Modern renders are not really suitable for application to old properties, they are flexible but relatively impervious (though they'll say otherwise) and can get algae growth if you live somewhere warm and humid. 'Traditional renders work far better; in my experience pebbledash is the best performer/ most robust if not as pleasing to the eye as smooth rendering.

If you have an old place without a cavity and want to insulate then there is some good guidance here: 

https://historicengland.org.uk/images-books/publications/eehb-insulating-so...

Some really interesting replies here, thanks.

Now I look up and down the street I can see that mould/algae/discolouration is much more noticeable on those houses with smooth render in a pale colour rather than those that are pebbledashed.

And the two builders on my road have ordinary unpainted pebbledash on their houses which tells me something too.......

My neighbour had his whole house done with K-Rend when he extended it to nearly double its original size a few years ago, including a side extension that runs right up to the boundary with our property.  It doesn't seem to have discoloured much if at all, unlike another house down the road which seems to have had the same finish (though maybe a different product that just looks similar) and now looks dreadful.

Said neighbour is, however, paranoid about his K-Rend, insisting that it is easily damaged, which doesn't sound great for an external wall coating, especially if that wall is immediately adjacent to another property - in our case, a drive that runs all the way to the back of our house (though we don't actually use it much ourselves since we got rid of the second car earlier this year).  He's fond of turning up and berating tradespeople working on our property who not unreasonably see the fairly broad drive as a good space in which to store and prepare materials and such like tasks, but who he seems to believe are intent on destroying his precious K-Rend.

My brother-in-law also has K-Rend on his house, and swears that it's tough as old boots.

I've no idea which of them is right.

If you don't stick to "if it ain't broke, don't fix it" and especially if you have a solid wall, consider a thinner variant of thermal render (but thick might mean new Windows too, depending...)

We have smooth render. The windward wall has massive cracks through it and is growing new and interesting flora. Other walls have similar but smaller cracks and damages which I've tried to patch up where I can. The whole thing needs re-done. It was last coated 5 years ago just before we moved in. We are going to get pebbledash. 

Edit: we live by the sea and are subject to stormy weather.

If you remove all the pebbles, it will be unclimbable. Then, we won't be able to argue about the grade at all!

The state of my pebbledash means my house is currently about E7 5a