Are Plaster Cracks Normal?

Plaster cracks are generally cosmetic and will not cause future problems if not addressed.

But unkeyed plaster is a problem that just gets worse and damages more and more of the surrounding plaster until it has broken so many keys that the plaster just falls to the floor.

Are cracks in plaster walls normal?

Vertical and horizontal cracks in drywall or plaster walls typically indicate drying and shrinkage, which is normal after construction. Jagged cracks, stair-step cracks and 45-degree angle cracks generally signify structural movement or settling issues that are occasionally serious but usually harmless.

Why is the plaster in my house cracking?

There are lots of causes of plaster blowing. For example in my house it was caused because there is salt in the walls from previous issues with damp. Cracks can appear between the ceiling and wall or around doors and windows.

When should I be worried about wall cracks?

Larger cracks that display these characteristics may indicate weaknesses in your property’s foundation:

  • One side of the wall is higher than the other.
  • Doors and windows no longer close in their frame.
  • Cracks are wider than about 5mm (or half a centimetre)

How do you fix hairline cracks in plaster walls?


  1. Spread the Joint Compound. Stir up the joint compound, then put a small portion on the edge of the six-inch taping knife.
  2. Apply Tape to the Crack. With the 6-inch knife, press the paper tape into the wet area, directly over the crack.
  3. Apply Joint Compound Over the Tape.
  4. Finish the Repair.

How do you fix cracks in plaster?

Fill the crack. Mix up a small batch of setting-type joint compound and use it to fill the crack and all the holes. Smooth the wet compound with a trowel; then, as it begins to harden, wet it and smooth it again. After the compound sets, sand the area lightly, then prime and paint.

What causes hairline cracks in plaster?

In drywall cracks often occur due to the movement of underlying framing materials, such as wood studs, or damage to tape seams between adjacent sheets of drywall. Particularly common following water damage, hairline cracks develop along the loosened edge of damaged drywall tape.

How can you tell if a crack is structural?

The 4 Basic Indoor Warning Signs

  • A door begins to jam or fails to latch.
  • Cracks appear in walls, especially over doorways, windows, or where walls meet ceilings.
  • Cracks open in vinyl or ceramic tile over a concrete floor.
  • Windows that used to open and close easily suddenly begin to stick or won’t close completely.

Can damp cause plaster to crack?

Plaster is likely to be damaged by movement or the results of external factors like impact or damp. Over time, plaster may delaminate or become detached from the surface beneath. Rotten laths can result in plaster sagging or bowing.

Can condensation cause plaster to crack?

Another sign of condensation is dark mould appearing on the walls and possibly the beginnings of a nasty, damp smell. Left untreated, condensation can cause wooden window frames to decay and damage the paint and plaster on the walls.

How do you fix cracks in settlements?



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How to Fix Cracks in Drywall – Sherwin-Williams – YouTube


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How do you fill hairline cracks?



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Filling small hairline crack in wall – YouTube


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Do subsidence cracks look like?

Cracks caused by subsidence are normally of a diagonal nature and will suddenly appear in plaster work inside the building and on brickwork outside. They will usually be thicker than fine hairline cracks, which may be caused by natural movement of a structure, and tend to be wider at the top.