What Is Roughcasting, and How Is It Different From Harling or
Four words, two methods, and a lot of confusion when you are getting quotes. Here is what each one actually me
Read thisSand and cement
The traditional one, and the cheapest. It is also the hardest, which is the catch: a hard render on a wall that moves cracks rather than flexing, and on an older softer wall it can do damage to the background.
It needs painting, and repainting. Use a breathable masonry paint rather than a plastic one, or you seal the wall.
Monocouche
A through coloured one coat render. The colour is in the material so there is nothing to repaint, and the face is scraped back to an even texture rather than trowelled flat.
It is a good answer on sound new blockwork. It is still cement based, so it is not the one for a wall that needs to breathe.
Silicone and silicone acrylic thin coat
A basecoat with mesh in it, then a thin through coloured topcoat. It stays flexible, sheds water, resists dirt and holds its colour, which is why it dominates new build and external wall insulation.
It is the most expensive of the three and it is a system rather than a material: the basecoat, the mesh, the primer and the topcoat are designed together and mixing brands is how a job fails.
Which suits your wall
New block, sound and stable: any of the three, and the choice is maintenance against budget. Thin coat silicone if you never want to paint it, monocouche for colour at a lower cost, sand and cement if budget decides and you accept painting it.
An older solid stone wall: none of the above as a default. That wall needs to let moisture out, which usually means a lime based harl, and putting a modern impermeable system on it moves the damp inside rather than curing it.
Want somebody to look at yours? Ring 07501 844432, or send a photograph of the wall on WhatsApp. If it is not a job for us we will say so.
Straight answers
Questions on this
Which render lasts longest?
A thin coat silicone system, properly installed on a sound background, with the least maintenance. The caveat is that any render only lasts as long as the wall and the detailing above it.
Can I put silicone render on my old stone house?
We would not, as a default. A solid stone wall has to let moisture out and a modern impermeable system traps it. We will look at the wall before saying.
Does render stop damp?
No, and anybody selling it as a damp cure is selling you the wrong thing. Render keeps weather off a wall. Damp coming from the ground or from a leak is a different problem with a different fix.
More guides
Other things worth knowing
What Changes the Cost of Roughcasting a House in Scotland
Why no honest tradesman can put a figure on this page, and the things that actually decide what yours comes to
Read thisIs It Worth Removing an Artex Ceiling?
Usually yes, and almost never by scraping it. Here is how the decision actually goes.
Read thisGet in touch
Tell us about the wall
Tell us what the wall or the room looks like now and we will come back to you with a price and a straight answer about what it needs.
Call us for your instant, no obligation quote
07501 844432. Or send a photo of the wall on WhatsApp.