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External wall insulation (EWI)

Solid Walls may sound like they should be better at keeping in heat but unfortunately the opposite is true.

Un-insulated solid walls can lose heat twice as fast as un-insulated cavity walls but insulating them externally could save you up to £435 each year and save 1770 kg/CO2/year* (*source: Energy Savings Trust).

Basically… the better insulated a property is, the less money you will spend heating it.

What is external wall insulation?

External wall insulation involves fixing a layer of insulation material to the outer wall of a property (which is not of cavity construction) then covering the insulation material with render or cladding.

There are many finishes available including smooth, painted, textured, tiled, panelled, pebble-dashed or brick slips.

We use several different systems like SPS Envirowall, Wetherby, Permaroc and Knauf. 

J&J Crump & Son External Wall Insulation 2 J&J Crump & Son External Wall Insulation 3

What is the process?

We will carry out a full technical survey of your property to make sure it is suitable for external wall insulation before any work is carried out.

The surveyor will check:

  • If the property is suitable for external wall insulation
  • Identify what items are need to be moved or extended on the areas being insulated and rendered
  • If the window and soffits have suitable overhang to except the system and discuss what is needed to achieve this if not
  • Discuss what type of insulation and finish if required

There are five stages to the process

When finished your home will have a great new look and have a maintenance-free finish that will not require decorating for many years which will help to save you money on your heating bills.

Stage 1

Erect scaffold if required and remove or extend all external wall furniture.

Stage 2

Attaching a supporting track around the bottom of the property at damp course level.

Stage 3

Fixing insulation boards to the external walls using a cement-based adhesive, followed by a mechanical fixing pin.

Stage 4

Applying a base coat render and glass fibre mesh to prevent cracking.

Stage 5

Apply primer and finish off with your chosen decorative finish.

What are the benefits of external wall insulation?

We will carry out a full technical survey of your property to make sure it is suitable for external wall insulation before any work is carried out.

  • Reduces heating bills
  • Disruption-free application
  • Improves weatherproofing and enhances sound resistance
  • Adds additional value to the property
  • No reduction to floor area of rooms
  • Increases the life expectancy of the external walls
  • Renews the appearance of external walls
  • Reduces condensation on internal walls and can help prevent damp
  • Helps to reduce draughts in the home
  • Protects your homes brickwork

Frequently asked questions

We will carry out a full technical survey of your property to make sure it is suitable for external wall insulation before any work is carried out.

Basically, a system of boards of thermally insulating material that are fixed to the building exterior and finished with a weather resistant, decorative render.

Up to 35% of heat lost from poorly insulated buildings escapes through the walls.

External wall insulation significantly reduces this heat loss, leading to a reduction in annual fuel bills by as much as 25%.

External Wall Insulation systems also protect the building structure, prevent deterioration, and overcome thermal bridging and condensation problems.

Far from it. External Wall Insulation systems offer a wide choice of decorative finishes that considerably enhance the visual appearance of a building. A full range of trims and accessories ensures that all detailing issues can be dealt with in an effective and visually attractive way.

Virtually all common types of construction – new build (from steel frame to solid masonry) or refurbishment (traditional and non-traditional house types).

Yes. Most solid wall insulation systems are manufactured and independently audited in accordance with ISO14001 Environmental Management Standard. External Wall Insulation systems incorporate insulation materials that are CFC and HCFC-free.

External Wall Insulation Systems Renders and Decorative Masonry Coatings are covered by British Board of Agrément certification.

After a job is completed you will receive a 25-year guarantee which is issued by SWIGA (The Solid Wall Insulation Guarantee Agency)

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