M Renovations

Repair & making good

Repairing lime plaster and render — not ripping it out.

Cracks, bulges, blown patches and water damage can usually be repaired in place. We patch, consolidate and re-finish lime plaster and render so it matches what surrounds it.

Most 'failed' plaster doesn't need replacing

The default trade answer to old plaster problems is to strip the wall and start again. It is usually the wrong answer. Lime plaster and render are designed to be repairable: cracks can be stitched and filled with compatible material, hollow patches cut out and pieced in, powdery surfaces consolidated, and detached areas re-adhered. Repair keeps original fabric, costs less disruption, and avoids the classic mistake of replacing breathable lime with modern gypsum that fails within a few winters.

What we repair

  • Cracked lime plaster — from hairline crazing to structural movement cracks, diagnosed before they are filled
  • Blown and hollow plaster — cut back to sound edges and pieced in with matching lime coats
  • Water-damaged plaster and render after leaks, floods or failed gutters
  • Salt-contaminated plaster around chimneys and at low level
  • Failing external render — patch repairs that key into the existing coats and match the finish
  • Previous bad repairs — gypsum, cement and filler patches removed and made good in lime

Diagnosis before repair

A crack is a symptom. Before we fill anything we ask why it happened: building movement, a failed lintel, moisture cycling behind an impermeable paint, vibration, or simply age. Repairs made without the diagnosis come back within a year or two — the same crack through the new filler. Where the cause is moisture, we trace it; where it is movement, we say whether it has finished; and where the plaster is simply old and tired, we tell you honestly how much life a repair will buy.

Matching the original finish

A good repair disappears. We match the mix to the original coats — binder, aggregate, hair — and the surface to its surroundings: polished, floated, or softly undulating on old walls. External patch repairs are worked into the surrounding render and finished so that after a coat of limewash the join is gone. Repairs in modern gypsum or cement filler never achieve this; they telegraph through paint and fail at the edges.

Where we work

Plaster and render repairs across South Wales and the West — Newport, Cardiff, Monmouthshire, Abergavenny, Hereford, Gloucester, Bristol and Swansea. Small repairs are usually batched by area, so tell us where you are and we will slot you into the right visit.

Considering plaster & render repair?

Tell us about the building and the work you are considering — photos help. We will come back with honest advice and a clear quote.

Get a quote

Common questions

Questions we hear most.

Can cracked lime plaster be repaired without replastering?

In most cases, yes. Hairline and shrinkage cracks are filled with compatible lime material; larger cracks are opened, stitched where needed and pieced in. Only plaster that has genuinely lost its key or turned to powder across large areas needs replacement — and even then, often only in patches.

Why does my plaster keep cracking after repairs?

Usually because the repair treated the symptom: rigid modern filler in a wall that moves, or repairs over a moisture problem that was never traced. Lime repairs flex with the building, and repairs made after proper diagnosis stay put.

Is it worth repairing old plaster rather than boarding over it?

Almost always. Original lime plaster is breathable, part of the building's character and — in listed buildings — protected fabric. Boarding over it traps moisture against the wall and loses the historic surface. Repair keeps the wall working as designed.

How much does lime plaster repair cost?

It depends on the size and cause of the damage, access, and how closely the finish must be matched. Small repairs are often modest jobs; we inspect, explain what we find and quote a fixed written price before starting.

Do you repair lath and plaster ceilings?

Yes — re-fixing loose plaster, patching in new lath and haired lime, and grouted reattachment where a ceiling is worth saving. See our guide to lath and plaster ceiling repair for how we decide between repair and reinstatement.

Related services

Other work we do.

Lime plasteringHeritage plasteringLime rendering

Where we work

Plaster & render repair across South Wales and the West.

South WalesNewportSouth WalesCardiffWest of EnglandBristolSouth WalesSwanseaSouth WalesMonmouthshireMonmouthshireAbergavennyHerefordshireHerefordGloucestershireGloucester
M Renovations

Let’s protect another piece of history.

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