Roughcasting and harling in Paisley

Roughcast cracked, blown or falling off in lumps? Tell us about the house and we'll pass it to one trusted local firm in Paisley, who'll come out, look at the walls and give you a price. It's free, and there's no obligation.

The firm does new roughcast on bare block or brick, full re-roughcasting where the old coat has failed, and smaller roughcast and pebble dash repairs. If you'd rather a smooth finish, they also do rendering and render repairs.

Why so many Paisley houses are roughcast

Walk round Foxbar, Glenburn, Gallowhill or Ralston and most of the houses you pass are roughcast. A huge amount of Paisley was built between the 1930s and the 1970s, both council housing and private semis and terraces, and roughcast was the standard finish. It was cheap to put on, it covered plain blockwork, and it kept the weather out.

The catch is age. A lot of that roughcast is now forty to ninety years old, and some has been patched several times by different people with different mixes. It's often the original coat, or a coat from a single redo decades ago, that's now cracking and coming away from the wall. In Scotland people tend to call it harling, especially on older stone houses, but it's the same job.

Signs your roughcast needs doing

• Cracks. Fine hairline cracks are common and not always a problem. Wide ones, cracks that run in long lines, and cracks that keep getting longer let water in behind the coat.
• Hollow patches. Tap the wall with your knuckles or the handle of a screwdriver. Sound roughcast gives a dull thud. A hollow, drummy sound means the coat has come away from the wall behind it, even if it looks fine.
• Bits falling off. Lumps on the path or the grass under a wall, or bare patches showing the block or brick, mean the coat has failed in that spot. Where one bit has gone, the area round it is usually loose too.
• Damp inside. A damp patch on an inside wall, especially one that gets worse after wind-driven rain, can be water getting through cracked roughcast. It can also be a leaking gutter, so it's worth checking both. Our blocked gutters page covers that side.
• Green or dark staining. Usually means part of the wall is staying wet, often from an overflowing gutter or downpipe.

One or two small problems can often be fixed with a repair. When the hollow patches are spread across the wall, or there's more patching than original, re-roughcasting the whole elevation tends to make more sense.

What's involved, step by step

New roughcast

On a new extension or a bare wall, the wall is cleaned and any loose material taken off. Corners and the edges round windows and doors get beads fitted so the finish has a straight, clean line. Then come the coats, described below.

Re-roughcasting

This is the more common job in Paisley, and most of the work is in getting the old stuff off.

1. Scaffold goes up. Paths, plants and windows get covered. On a two-storey house there's no safe way to do this from ladders.
2. Hacking off. The old roughcast is broken off the wall, usually with power tools. It's loud, dusty and the slowest part of the job. How long it takes depends on how well the old coat is stuck on: blown roughcast comes away easily, while sound patches fight back.
3. Repairs to the wall. With the wall bare, the firm can see the blockwork or brick underneath. Cracked blocks, crumbling joints and gaps round window frames get sorted before anything new goes on. This is where surprises can turn up, and why a fair quote mentions it.
4. Scratch coat. A base coat of render is put on and scratched while it's soft, so the next coat has something to grip.
5. Dash coat. The final coat is a wet mix with small stones or chips in it, thrown onto the wall rather than smoothed on. That throw is what gives roughcast its texture, and it takes a practised hand to get it even across a whole wall.
6. Finishing. Edges get tidied, beads cleaned, and the house can be painted if you want a coloured finish. Scaffold comes down once everything's set.

How long it takes

For a typical Paisley semi, most jobs take somewhere between one and two weeks of working days. A terrace with just a front and back elevation can be quicker, and a big detached house slower. The things that stretch it out are the weather, how hard the old coat is to remove, and how much repair the wall needs underneath.

Weather matters more than people expect. Roughcast can't go on in frost, in heavy rain, or onto a soaking wet wall. In a west of Scotland winter that can mean losing days at a time, so if the job isn't urgent, spring through early autumn gives the firm the best run at it.

What affects the price

We don't put prices on this page, because two houses on the same street can cost quite different amounts. Our roughcasting cost guide has typical ranges. The things that move a quote are:

• Size and number of walls. A mid-terrace has two elevations to do. A detached house has four, plus any extension or garage.
• Height and scaffolding. Two storeys need full scaffold. Steep gardens, conservatories and narrow side paths make it harder to put up.
• How much has to come off. Hacking off a full coat takes far longer than going over a sound one.
• Repairs underneath. Cracked blocks, rotten lintels or damaged window surrounds add time and materials.
• Finish and colour. A painted finish, a through-coloured mix or a change of chip size all change the cost.
• Access and the neighbours. On semis and terraces, the join with next door needs care. Some neighbours decide to get theirs done at the same time, which can make sense for both of you.

While the scaffold is up

Scaffolding is a big part of the cost of any job at height. If it's going up for roughcasting, it's worth thinking about anything else that needs doing up there. Gutters and downpipes are the obvious one: a leaking gutter is often what damaged the roughcast in the first place, so it should be fixed before the new coat goes on. Our pages on gutter cleaning in Paisley and fascia and soffit cleaning cover that work.

The roof is the other one. Loose ridge tiles, slipped slates or worn flashing are much easier to get at from a scaffold that's already there. If you've been meaning to get the roof looked at, say so, and see our page on roofers and roof repairs in Paisley.

If you live in a flat or a terrace

In a four-in-a-block or a cottage flat, the walls are usually shared with the other owners, and so is the cost. Everyone affected needs to agree before work starts, and it helps to get one quote covering the whole building. Mention it on the form and the firm will know to price it that way.

Not sure whether you want roughcast or something smoother? Our guide to harling, roughcast and pebbledash explains the differences in plain English, and the Renfrewshire roughcasting page covers the towns around Paisley.