About CWISC

The Cavity Wall Insulation Self Certification scheme (CWISC) provides homeowners with the comfort of knowing that work by registered contractors complies with the requirements of the Building regulations. The scheme is operated by The Installation Assurance Authority (IAA) and has been approved by the Department of Levelling Up Communities and Housing (DLUHC). Since it’s authorisation in 2010 over 1 million installations have been completed under the scheme, meaning that it is one of the largest Competent Persons Schemes.

Registered installers under the scheme must comply with detailed technical requirements and installations are subject to regular independent inspections and audits to ensure that work complies with the Building Regulations. A copy of the scheme rules is available here.

A list of registered installers is available on this website, and can be used to check an installer is registered with CWISC or to locate registered installers locally. Shortly after completion of the work a certificate of conformity will then be forwarded by post. This is an important document that you will require if you move or sell your home, so should be kept in a safe place but duplicates are available for a small charge. Qualifying installations also receive an IAA independent 25 year Guarantee against defects in materials and workmanship.

To date The CIGA Group has issued over 6.2m Guarantees, which, together with the certificate of conformity with the Building Regulations provides householders with complete peace of mind. In the unlikely event that you are dissatisfied with the service provided by CWISC please see our complaints procedure.

There is no annual fee or joining subscription for installers who are members of The IAA to be accredited under CWISC. Once admitted to membership, a fee is charged for each job completed under the scheme, which is included in the cost of the guarantee at a nominal charge of £1. Non IAA PAS certified members can be considered for membership of CWISC at a charge of £1,000 p.a. and £1 per notification subject to meeting the necessary CPS standards and The IAA having data sharing arrangements in place with any alternate PAS Certification provider.