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Frequently Asked Questions

What is External Wall Insulation?


External Wall Insulation (EWI) is a system of thermally efficient and attractive wall insulation, offering both energy efficiency and exterior protection to structures. Insulation is fitted to the outer walls of a building, covered with specialist render cladding and finished in a colour and texture of your choice, ensuring aesthetic appeal is striking and durable. The system can be applied to new construction projects or as part of a refurbishment on either high or low-rise buildings to deliver high performance insulation that is guaranteed to conserve energy and eliminate condensation related issues. Finishes may be smooth, textured, pebble-dashed or complete with brick slips for a contemporary and suitable appearance for any project.

external wall insulation

What are the Benefits of External Wall Insulation?


Lower fuel bills
High insulation levels achieved by the installation of an EWI system result in significant savings in energy bills.

Annual saving
One of the benefits of external wall insulation is that an average solid-walled semi-detached house could typically save £385 per annum (figures supplied by EST). This increases with greater insulation thickness.

Prolongs building life
Weather protection is guaranteed for the building façade with use of an EWI system. Alumasc systems have an assessed minimum life of thirty years.

Improved building appearance
An extensive range of colours and finishes are incorporated into each EWI system, ranging from silicone-textured renders to brick-effect finishes.

Eliminates condensation
Interstitial and internal condensation can be minimized with an EWI system, in turn eliminating associated problems such as damp internal walls and mould.

Minimal disruption
One of the benefits of external wall insulation that is often not considered is that internal space is not infringed upon. Occupants may remain in the comfort of their homes during installation.

What Should I know about Installing an EWI System?


Is my property suitable?
K Systems has been supplying EWI products and systems into the market for over thirty years. During this time, a range of solutions have been developed to suit every building and construction type, whether they are solid wall, concrete, timber or steel framed.

Can I install EWI myself?
Installing EWI yourself may save you money compared to installing through a hired company, although carrying it out yourself is not recommended. Little experience may result in problems to your home and further expenses down the line. To ensure a robust and professional product, it is worthwhile choosing an experienced firm to carry out the installation.

What disruption can I expect?
As the installation is external, the disruption is minimal in comparison to internal wall insulation installation. Drilling and mixing equipment will be in use and scaffolding may be required, though the approved installer will assure you are fully informed of the programme of works before the installation begins.

Will I feel the difference once installed?
Yes – the effects are instant. You will no longer need to heat your home as often or for as long as prior to installation and there will also be acoustic benefits. Additionally, the effects are felt throughout the summer, since your home will be less susceptible to temperature fluctuations during the warmer months.

How much money can I expect to save post installation?
An average solid-walled semi-detached house could typically save £385 per annum (figures supplied by EST). This increases with greater insulation thickness.

Figure 5 – ETAG 004 Hard Body Impact Tests

How does an External Wall Insulation System benefit my home?


Does EWI add value to your home?
Carrying out any energy-saving renovations on a property increases its EPC (Energy Performance Certificates) score and increases its value. Choosing to install an EWI system contributes greatly to increasing your home’s EPC score through savings on energy bills and eliminating the risk of condensation-causing defects.

To what extent can EWI improve the U-value of my home?
EWI systems are efficient in reducing a property’s energy bills through increased thermal energy conservation. Up to a third of energy loss occurs through poorly insulated walls, so overcoming this issue with sufficient insulation certifies an improvement in a home’s U-value.

Does EWI prevent damp?
The effects of condensation can be mitigated with an EWI system. Masonry bricks are kept warm by the external insulation which ensures condensation is prevented; there is a smaller difference in temperature between the wall fabric and the air within the property. Damp internal walls and mould can be avoided and eliminated, providing walls are dry prior to installation.

How long does EWI last?
K Systems have an assessed minimum life of thirty years, although many achieve a rating in excess of this.

Would you like to learn more about our EWI systems and discuss your next project with a member of our team? We would love to hear from you!

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