Structural surveys

The causes of problems

Types of movement

Types of movement

Raking Crack

A crack which runs diagonally across a wall. Typically it will follow the mortar joints but it can also cross bricks. Damage to bricks is very much dependent on the strength of the mortar.

Vertical Crack

A crack which runs vertically (or close to this) up a wall. The direction must be vertical but it may follow mortar joints. This type of cracking can be caused by insufficient movement joints, particularly in block walls.

Settlement Crack

This generally refers to the cracking that frequently occurs in the first year or so after a structure is finished.

General

Although similar problems tend to result in similar crack patterns, expert advice should always be sought. Below are We have compiled a page on Crack Patterns and please note that it is. Every property is different and should be treated as such. In order to help explain how the cracks develop we have an animation below. These are meant as a general guides only.

Lintel Failure
When a Lintel (Beam) over an opening deflects excessively the crack pattern shown is typical.

The problem can be caused by a lintel that is adequate but 'bendy'.  On the other hand it can be indicative of an section.

lintel failure tends to be found in older properties in particular where timber lintels have been used.

In addition to deflection problems, crushing at the support can lead to cracking.  Again this is more likely with a timber member due to the presence of rot.

Floor Slab Movement
The most likely problem is settlement. This is often due to the hardcore being inadequately compacted but can also be the result of soft ground below the hardcore.

Floor slabs can also be attacked by sulphates in the ground water. The concrete expands with consequent damage to the floor and sometimes the walls. A prime cause of this is when colliery shale has been used for the hardcore - it has a high sulphate content.


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