Rateavon Jersey

Render & Insulations

A Guide to External Wall Insulation

Why Choose EWI?

  • Makes your home instantly warmer
  • Saves you money on your heating bills
  • Reduces heat loss & energy waste
  • Improves the look of your property
  • Increases the value of your home

The process is relatively simple, but does require the experience of fully trained and approved installers.

Install insulation to outer leaf. Thickness and type will be calculated to provide maximum thermal performance

Apply a fully reinforced layer of basecoat render, engineered to provide flexibility & durability

Final coat of decorative silicone based topcoat finish, coloured to suit your requirements

What is External Wall Insulation?

External Wall Insulation (EWI) systems, by definition, are applied to the exterior of a property offering improved energy efficiency, weather protection and building aesthetics.

An EWI system consists of rigid insulation boards fixed to the exterior walls of a property creating a ‘thermal jacket’, which is then over-coated with a weather protective, breathable, hard wearing, attractive polymer modified render.


Why Choose an External Wall Insulation System?

Your property could be losing up to 45% of its heat through the walls alone (figures provided by EST). EWI systems can help reduce this significantly whilst providing numerous other benefits to the householder.

  • Lower Fuel Bills: Extremely high insulation levels can be achieved over other forms resulting in savings on energy bills. An average solid wall semi-detached home could save around £375 per year on fuel costs (figures provided by EST).
  • Condensation: EWI can eliminate interstitial and internal condensation. Associated problems such as damp internal walls and mould growth may also be overcome.
  • Prolonged Building Life: External Walls of the building are protected from the effects of the weather. Some systems have an assessed minimum life of 30 years.
  • Building Appearance: EWI systems come with an extensive range of decorative finishes and colours, from the traditional brick finish to the more modern silicone textured renders and many in between.
  • House Value: Having an EWI system installed to your home can increase the value.
  • Installation: Because EWI systems are installed externally you never have to leave the comfort of your own home during the installation and internal space is not infringed upon.
  • Warranty: EWI systems come with a 10 year materials and labour warranty.
  • Funding: Some partial funding may be available depending on property and circumstances.
  • Sound Proofing: EWI systems also offer a level of acoustic resistance, reducing the effects of traffic noise.
  • Fire Protection: Recognised EWI systems have been assessed and approved by the BBA and BRE.

Choice of Finish – Durable, decorative and virtually maintenance free.

The range of finishes available with EWI systems includes a choice of weather resistant, decorative renders offering superb technical performance.

  • Through Coloured Silicone Textured Render – Available in over 600 colours and in 3 different textures.
  • Mineral Topcoat – 1.5mm white textured render that can receive paint.
  • Masonry Paint – Available as a silicone or emulsion paint, for the more traditional looking finish.
  • Dry Dash – Hard wearing traditional pebble dash finish.
  • Rendabrick – Brick Effect render.
  • Traditional Brick Slips – Real brick slips, giving the impression of a traditional brick wall.

Render Finishes



Frequently Asked Questions

How much will it cost?
As property types vary please contact us on 741439 for a free detailed quotation.

Is my home suitable?
EWI systems have been developed to suit every building and construction type, whether they are solid wall, cavity wall, concrete, timber or steel framed.

What are the main benefits?
Your annual fuel bills will decrease by up to 25% whilst improving the appearance, value and durability of your property.

Will I feel the difference once installed?
Yes – the effects are instant. You will not require the heating on as long or as often and there will also be acoustic benefits. The effects will also be felt in the summer months, with your property less susceptible to temperature fluctuations.

Are there grants or funding available?
In the UK there is Government funding and grant schemes available, however in Jersey the States are still detailing the Energy Policy and Eco-Active identify EWI as a major benefit to reducing CO2 emissions and promoting energy efficiency.

Do I need Planning Permission?
Due to new Planning requirements, any material change in the roof covering or façade will require Planning Permission before works can proceed. Rateavon can assist you through this process (subject to application costs).

Who installs the system?
Rateavon have a team of trained applicators in all systems

How durable is the system?
EWI systems have a minimum effective life of 30 years, subject to ongoing maintenance. 

Ask us a question…