Cavity wall insulation FAQ

Q. What is cavity wall insulation?

Cavity wall insulation is a system whereby material is injected into the gap (or cavity) between a property’s inner and outer walls to help prevent heat loss. There are many different types of insulation which can be fitted, such as Thermabead Diamond or mineral wool fibre. As such there is a type of insulation suitable for most properties which were built with cavity walls.

Q. What are the benefits of having cavity wall insulation fitted?

Houses built with cavity walls generally have thermal performances which are well below the standards required by current building regulations. This means that insulating the walls could not only significantly reduce the heat lost from your home and decrease your heating bills by up to £135, but it can also help to reduce your carbon footprint by around 550kg every year*.

*According to the Energy Saving Trust website, Jan 2013.

Q. How is cavity wall insulation fitted?

Each elevation of the property has small holes carefully drilled out in compliance with BBA specifications. Insulation is then blown via a long hose into each of the property’s elevations. Once all walls have been insulated, the holes are then filled and the site is returned to its previous state.

Q. What types of properties can be insulated?

Cavity wall insulation is suitable for most homes which have a cavity space of at least 40-50mm between bricks, and held together with wall ties. 99% of properties which traditionally couldn’t be insulated because the standard BBA drill pattern could not be followed can now be insulated using Domestic and General’s Thermascopic Bead Lance. The Lance allows for a complete cavity fill by drilling only the end of the wall.

Q. Will the technicians need to come into the house?

In order to comply with health and safety regulations, the technicians are required to carry out pre and post installation checks in your home. These checks include assessing whether or not your home has adequate ventilation in place to prevent carbon monoxide poisoning and mould growth. It might also be necessary for the technicians to internally drill some of your walls for access issues, but this will be discussed with you by the surveyor.

Q. Does anything else need to be done prior to installation?

We recommend that any valuables are removed from walls, shelves or windows sills on any external walls prior to installation, as the drilling can cause vibrations.

Drilling the walls also unavoidably causes dust. To avoid as much disruption as possible, we recommend that all windows and doors are closed before the installation proceeds, and your neighbours are informed so that they can do the same. We also suggest that anything outside your home which may be affected by the dust, such as vehicles or clothes on the washing line, are removed from the areas to be insulated.

To avoid any delays in your installation, it is also necessary to ensure that there is adequate parking close to your property for a Luton Box van.

Q. How long will the installation take?

An average sized property could take between 2-3 hours.

Q. Is the cavity wall insulation guaranteed?

A 25 year guarantee is supplied for each property by CIGA, the Cavity Insulation Guarantee Agency. It is sent directly to each customer 8 – 12 weeks after the insulation is installed. The guarantee is transferable to any subsequent owners of the property.

Q. How long does the insulation last?

Cavity wall insulation should last for the lifetime of the house.