"High build"

Smiley Dan

New Member
I've sand and cement render on my house. Some of it is shot, but most of it is still on very nicely. There are also quite a lot of small cracks.

I want to fix the cracks once and for all (or at least for a couple of decades). I was going to have the render taken off and a silicone render applied.

A local builder visited and suggested taking the render off will be a huge job (> 220m2) especially where the render is sound and we might damage the blockwork underneath. Instead he suggested patching all the shot bits and cracks and then putting a layer of "high build" on.

The main advantage, he said, is that when cracks form (which he seems to think will inevitably happen to all renders including silicone based ones) you don't have to grind out and re-render the crack, you just repaint this high build stuff back on and make good.

This is new to me so I'm a little uneasy taking this advice; furthermore the lack of trust in modern renders is also a bit new to me. Some people (mostly architects it must be said!) seem to think they are the answer to everything. So I'm a bit confused.

My other concern is: can you get smooth versions? They look a bit overly textured to me. I want a modern look.
 
There was a few plastic coating companies around that did this. Some good some bad. But if you take off all loose back to sound and then patch up correctly you should be able to plastic coat it with good results.

Make sure what ever render you don’t take off is sound and clean.
 
Could you name the good companies you remember?

The builder who mentioned this approach calls the installer a "painter" - I guess it's relative; to a builder this stuff is paint. To a painter, it's probably render ;-)
 
for a modern finish, i would repair the shot render, then apply a coat of parinter with a full mesh and an acrylic finish.
 
for a modern finish, i would repair the shot render, then apply a coat of parinter with a full mesh and an acrylic finish.
Thanks for that reference, I'll look into that. Although I'm not sure about acrylic - this is a slightly exposed location, I thought silicone might be better - can you have a silicone topcoat?
 
I was applying high build before acrylic and silicone thin coat took off, I've put 10s of thousands of litres of it on, it's s**t and expensive, lots of painters use to roller it on, renders would trowel it on and use a honey comb roller to give the heavy texture no much else you can do with it, long term durability is crap on sand and cement and paint,
 
Oh, in that case I'll add a bit more that I've found out, I didn't before because I thought it was off topic.

Turns out there's this type of paint called "elastomeric" paint. These are paints that can stretch and can apparently cope well with hairline cracking. Example: Bedec Extra Flex. There are also firms that will do the install for you, e.g. a product called Secoflex.

So I'm going to try to get some more advice about these. There's a good local independent paint shop plus there's Brewers nearby which stock the Bedec.

My concern with the paints is it looks like they are generally a little shiny - I'd rather have a matt.
 
Oh, in that case I'll add a bit more that I've found out, I didn't before because I thought it was off topic.

Turns out there's this type of paint called "elastomeric" paint. These are paints that can stretch and can apparently cope well with hairline cracking. Example: Bedec Extra Flex. There are also firms that will do the install for you, e.g. a product called Secoflex.

So I'm going to try to get some more advice about these. There's a good local independent paint shop plus there's Brewers nearby which stock the Bedec.

My concern with the paints is it looks like they are generally a little shiny - I'd rather have a matt.

Johnstones with pliolite stretches.
 
I thought high build was thick Sandtex. And used sponge roller with holes in to pull material out to cover cracks and give rough finish. .
 
There was a few plastic coating companies around that did this. Some good some bad. But if you take off all loose back to sound and then patch up correctly you should be able to plastic coat it with good results.

Make sure what ever render you don’t take off is sound and clean.
Rigsby is it a race to stay fit and healthy the older u get
 
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