Cavity Wall Insulation Technician

The Job and What's Involved

Cavity wall insulation technicians, also known as thermal insulation installers, insulate the space between the walls of new and existing buildings by pumping in insulating materials. They load the materials they need for a job into a van, and travel to the site. On arrival, they check that the cavity is suitable for filling and make a note of the decision, together with any comments on the state or age of the building.

Government statistics show that about one third of the heat lost by a building without insulation is through the walls. Insulating cavity walls and roof spaces saves money on heating costs and can contribute towards the soundproofing of rooms within a building.

A cavity wall insulation technician normally works alongside another tradesperson and begins by drilling small holes in the walls of the building. The holes are drilled to a set pattern, using handheld electric or pneumatic drills. Insulation technicians drill from the outside when working on existing buildings, and from the inside on new buildings. They work from ladders or, on tall buildings, from scaffolding platforms or cradles.

They calculate the amount of wool, foam or bead required for insulation. They then pump the insulating material into the cavity between the walls, using a machine designed for this purpose. On completion, they check that the whole cavity has been filled, re-point the drill holes to match the existing mortar, clean up and clear away their equipment.

There are no set working hours, but cavity wall insulation technicians may work around 45 hours a week, which may include weekends. There is more work in the winter when people feel the need for insulation.

Much of the work takes place outdoors, in all weathers. Conditions can be dirty, cold, wet and dusty. The work involves climbing, lifting, standing and bending.

The work may also involve travelling to different sites, and can occasionally mean staying away from home. It may help to have a driving licence.

The starting salary for a cavity wall insulation technician may be around £15,000 a year. Overtime payments can significantly increase salaries. Lodging and tool allowances may be paid.

Getting Started with this Career Choice

The cavity wall insulation business is made up of firms of varying sizes, from under ten employees up to several hundred. Most firms are located in urban areas. Many cavity wall insulation technicians are self-employed.

Government support for better insulation standards in older buildings may result in more work and improved wages.

Education and Training

No set academic qualifications are required. GCSE's (A-E) in English and maths are an advantage, as cavity wall insulation technicians need to be able to calculate quantities and keep written records.

Apprenticeships and Advanced Apprenticeships provide structured training with an employer. As an apprentice you must be paid at least £95 per week; you may well be paid more. A recent survey found that the average wage for apprentices was £170 a week. Your pay will depend on the sector in which you work, your age, the area where you live and the stage at which you have arrived in the Apprenticeship.

Entry to Employment (e2e) can help to prepare those who are not yet ready for an Apprenticeship. In addition, Young Apprenticeships may be available for 14- to 16-year-olds. More information is available from a Connexions personal adviser or at

There are different arrangements for Apprenticeships in Scotland, Wales and Northern Ireland.

For further information visit My World of Work, Careers Wales; and for Northern Ireland contact

It is important to bear in mind that pay rates for Apprenticeships do vary from area to area and between industry sectors.

A Few More Exams You Might Need

Training follows British Board of Agrement (BBA) and BSI British Standards regulations.

Trainees work with experienced cavity wall insulation technicians and may be required to attend short classroom courses run by the manufacturers. It takes three to six months to become proficient.

Trainees learn how to use various tools, the difference between the materials used for insulation, and how to repair the drill holes, making sure they match the original wall surface.

It may be possible to work towards NVQ's in insulation.

Most training is now carried out by installer companies, with special courses for safety awareness when working on flues and chimneys.

Featured Job Guide - Oil Drilling Roustabout

Oil Drilling Roustabout

Oil Drilling Roustabouts and Roughnecks work as part of a small team on offshore oil or gas drilling rigs or production platforms. Roustabouts do unskilled manual labouring jobs on rigs and platforms, and Roughneck is a promotion from roustabout.

Roustabouts do basic tasks to help keep the rig and platform working efficiently and Roughnecks do practical tasks involved in the drilling operation, under the supervision of the driller.


Skills and Personal Qualities Needed

Cavity wall insulation technicians should:

  • Have mechanical aptitude for operating and maintaining the machine which blows or pumps insulating material into the cavity.
  • Have hand skills, for operating drills.
  • Be able to follow written and spoken instructions.
  • Be able to work and co-operate with other people, including customers.
  • Be physically fit, as the work is hard.
  • Be able to work at heights.
  • Have some organisational and planning skills.

Your Long Term Prospects

There are limited opportunities for promotion, but a few larger companies may offer the possibility of progression to team leader and then to supervisory posts.

Cavity wall insulation technicians with experience can become self-employed.

Get Further Information

British Board of Agrément (BBA),
PO Box 195, Bucknalls Lane, Garston, Watford, Hertfordshire WD25 9BA
Tel: 01923 665300

The Chartered Institute of Building (CIOB),
Englemere, Kings Ride, Ascot, Berkshire SL5 7TB
Tel: 01344 630700

National Insulation Association Limited,
3 Vimy Court, Vimy Road, Leighton Buzzard LU7 1FG
Tel: 01525 383313

Other Related Jobs

Additional resources