Cavity Wall Tie Inspection

Cavity wall construction is now the most common method of construction and has been in place since the early 1900's replacing the solid wall method. By the 1920's it became more widespread and was used as standard from the 1940's onwards. Cavity wall constructed properties built between 1900 and 1980 normally have either zinc strip ties (fishtail) or wire ties (butterfly) and due to the nature of mild steel are susceptible to corrosion.

Corrosion of ties is common, particularly in exposed coastal areas or areas where prevailing wind and rain are found. Corrosion is also accelerated by high levels of salt or where absorbant building materials, such as stocks, are used, allowing moisture penetration to the outer skin of brickwork to occur.

Why do I need a cavity wall tie inspection?

Whether it be a recommendation by a chartered surveyor or whether you have noticed horizontal cracking, bowing or bellying to your walls, a cavity wall tie inspection will determine if wall tie failure is the cause. It is important to note that these symptoms can  sometimes be the result of a different (and sometimes more serious) structural defect, in which case the advice of a structural engineer must be sought.

The recommendation for a cavity wall tie inspection is often given by companies that are about to install cavity wall insulation, to check the condition of the ties, as inspection of them thereafter can sometimes be difficult or impossible.

What is involved?

Darroch Remedial Inspections will observe the specific site conditions, and locate a number of ties with the use of a metal detector. Once located, the ties are marked and the surveyor will drill through the outer skin adjacent to the ties allowing access for the endoscope to be inserted into the cavity to view their condition. The holes are then filled and a full written report is issued to the client giving full details of the inspection, the condition of the wall ties and any necessary recommendations for remedial works, including specifications, drawings and estimated costs for budgeting purposes.