DIY & Building Basics How To Spot And Deal With Cracks

Date Published:

28/05/2008

A slight and natural movement of the building or a symptom of a wider problem? Find out how to diagnose your cracks.

No one likes to see cracks appearing in their walls. Most will be just surface disturbances of the plaster caused by your home expanding and contracting naturally (or breathing as it is sometimes known). New homes can be plagued in the early months of occupation by minor cracks caused by the home settling. For the most part these cracks, though often unsightly, are benign. Just like finding a physical discrepancy in your own body like an suspicious mole or lump, however, it is worth getting to the bottom of what is causing the crack.

A crack is actually the visible symptom of a possible problem, and not the problem in itself. There is no one definitive cause for cracks but the minor changes in the temperature and moisture within building materials can be enough to cause hairline fractures in a surface. Vibrations from traffic, particularly if your house is over a ridge can cause problems, and clearly subsidence can be a more serious root cause of structural cracks.

Homes built above former mine workings, landfill and other possibly mobile ground can be most susceptible to structural cracks of this kind, and really prevention is better than trying to find a cure. Before you buy a house, ensure you have commissioned a rigorous environmental search for possible problems. Also walk along the roads in your area. Are there clear signs in neighbouring properties that bay windows may have been underpinned or re-pointed recently? The neighbouring houses converted into rental accommodation or multiple residences will often be a giveaway. Where there is no responsibility for the exterior upkeep by the tenant or where the freehold of a series of flats held by an external party, costly remedial work like underpinning will often not be a high priority.

While most cracks will prove to be benign, it is worth monitoring them for any signs of growth. If you have a digital camera take a photograph every week of so and compare your most recent image with the first. Otherwise try to retain a visual image of how far the crack was progressed by mentally mapping it in relation to other features on the wall such as hanging pictures etc. If a crack appears suddenly and progresses rapidly, perhaps even showing evidence of progressing to the exterior of the building then you will need to consult a chartered surveyor.