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Guide to External Wall Insulation

What is External Wall Insulation?

External wall insulation systems are an energy efficient measure designed to upgrade thermal performance and the external appearances of a property or building.

Over a third of the energy required to heat a property escapes through the external walls.

External Wall Insulation (also known as an Insulated Render System / Solid Wall Insulation) is the perfect solution for ‘hard to heat’ homes.

The system involves the mechanical and/or adhesive fixing of insulation boards to the outside of a property. This is followed with a mesh reinforcement, a base coat and a final decorative finish. This layered method encases the property and helps prevent heat from escaping unnecessarily.

Wetherby have an impressive portfolio of systems allowing clients to confidently specify a flexible building solution that not only conforms to current building regulations and energy standards, but offers a wide choice of facade finishes to fully meet the client’s aesthetic expectations.

Why External Wall Insulation?

External wall insulation is a means to prevent heat loss or heat gain by creating a barrier between two areas that are significantly different in temperature. Insulation is not designed to keep the cold out but to slow the loss of heat from the home. Effective use of insulation has the ability to reduce heat loss during the cold weather and also keep your home cool during warmer weather.

Homes build before the 1920s are more likely to have solid walls as opposed to cavity walls. Solid walls tend to lose twice as much heat through un-insulated walls and with no cavity to inject insulation into it makes them hart to heat homes.

By adding external wall insulation to solid wall properties you could be making these estimated annual costs and CO2 savings.

Savings with External Wall Insulation

External Wall Insulation (England, Scotland, Wales)
Type of PropertyApprox. Savings per yearApprox. CO2 Savings per year (kg)
Detached house (four bedrooms) £4551,900
Semi-detached house (three bedrooms)£2601,100
Mid-terrace house (three bedrooms)£175720
Detached Bungalow (two bedrooms)£180740
Mid-floor flat (two bedrooms)£145610

Table notes: figures based on a typical gas-heated home. All data obtained from the Energy Savings Trust (EST)

Wetherby External Wall Insulation Systems have a variety of systems and finishes to suit all property types that will not only improve insulation values, but also help to reduce heating bills and carbon emissions.

What are the benefits of EWI?

For properties in need of refurbishment, they are a flexible, cost-effective alternative to demolition. In addition, because all Wetherby systems are designed to be strong and weatherproof it means water ingress and damp are eradicated.

Here are some of the top benefits you can achieve by installing a Wetherby EWI system:

  • Upgrades properties in line with current Building Regulations
  • Helps to reduce energy bills
  • Reduces condensation, heat loss & CO2 emissions
  • A cost-effective alternative to demolition & rebuilds that can add value to a property
  • Improved acoustic and fire resistance properties
  • No need for occupants to move out during installation and no loss of internal floor space
  • Protects the building fabric against the effects of weathering and revitalises a buildings appearance
  • Has a positive effect on the environment, improving the attractiveness of a local area

For more information about Wetherby’s External Wall Insulation Systems visit our website here!

We always recommend using a recognised installer when incorporating any external wall insulation system; to find a list of recognised installers in your area click here!

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