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External Wall Insulation, or EWI, is the application of insulating boards onto the external walls of the house. 

We offer a number of finish options to make your home look really unique – from your choice of through coloured high quality render, to brick slips produced from real bricks, pebble-dash, brick effect render
, timber cladding and other speciality finishes.

 External Wall Insulation can offer a complete enclosure around the heat loss perimeter of your home which can be difficult to achieve with other forms of insulation.  Improving your homes energy efficiency in this way reduces heat loss substantially making it easier to heat and keep warm while saving you money on energy bills and reducing your carbon footprint.

Suitable for all wall types but particularly homes constructed prior to the 1920’s which likely have a solid wall construction. Installing External Wall Insulation to solid walls will greatly improve the thermal performance of your property.

How Is External Wall Insulation Installed?

Firstly, if the property has existing render, a render test must be carried out to see if it is strong enough to hold the insulation. If not, we will remove all the existing render before attaching the insulation to the brickwork.

If the render test shows that the existing render is firmly held in place, the render can be smoothed. This will then be ready for the External Wall Insulation to be applied directly on to it.

Removing pipework from the outside of the building is another important step before installing any External Wall Insulation. These will be reinstalled at the end of the process (and may be extended in some instances).

We can also replicate architectural features of the property such as stone window cills and lintels along with other important features to maintain the character of your home.

Solid Wall Insulation

Advantages of External Wall Insulation

  • Lower heat loss and energy bills

  • Transform the appearance of your home​

  • Solve problems with the existing wall finish

  • Low maintenance system

  • Offers total weather protection; virtually eliminates internal wall condensation and removes the chilly, damp atmosphere

  • Warmer house in winter and cooler house in summer

  • No disruption inside your home and no reduction in internal floor area

  • Increased sound resistance

If you are interested, please don't hesitate and CONTACT US now to arrange a free consultation with a member of our team of experts.

Different types of Insulation

There are a number of different types of insulation that can be used for External Wall Insulation. Not all materials perform the same. For example, numerous other installers will offer expanded polystyrene boards or EPS to insulate your walls but they do not perform as well as other materials at insulating your home. 

Our Top Choice - Kingspan Phenolic Foam

Kingspan Phenolic Foam has excellent thermal performance comparatively to other products.

It also meets the regulations laid out by building control at a thinner thickness than other materials meaning a minimised impact to the aesthetics and proportions or your home.

The key factors you need to take into account for each type of insulation are:


  • Fire rating

  • Thermal performance (how well it insulates relative to its thickness)

  • Durability

  • Biodegradability and environmental impact

  • Moisture resistance

Considerations with EWI

  • Planning permission is likely to be required if you live in a conservation area or your house isn't already rendered. We will work your planning application for you through to approval

  • Homes in conservation areas might be restricted to certain finishes

  • It needs a specialist to design the system and install it properly - this is what we do day in and day out

  • It must be correctly fixed so that it does not bridge the damp proof course or cause cold bridging

  • Rising damp must be rectified before fixing the insulation, again one of our specialties

If you are interested, please don't hesitate and CONTACT US now to arrange a free consultation with a member of our team of experts.
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