Heat energy can be transferred out of your house by three basic mechanisms – conduction, convection and radiation. Un-insulated external walls are responsible for 35% of your home’s heat losses. Air leakage is also common phenomenon in un-insulated roofs with a 25% heat of losses. Most common insulation materials work by slowing conductive and convective heat flow. So, there is an imperative need to insulate your house in order to reduce the energy escaping from your property. External wall and loft insulation has a number of benefits as follows.

1. EWI Improves energy efficiency of your home

Heat flows from warmer to cooler spaces until there is no longer a temperature difference. Insulation helps to reduce heat losses in cold weather and heat gains in warm weather. It provides resistance to heat flow and works as a barrier that protects the indoor environment from the outside weather conditions. By installing wall and loft insulation the air leakage rate of your house will be reduced dramatically and your heating and cooling bills will be cut by up to half.


Solid wall insulation – external walls
Type of property Installation cost Savings per year
Detached house (four bedrooms) Between £5,000 and £18,000 £455
Semi-detached house (three bedrooms) £260
Mid-terrace house (three bedrooms) £175
Detached bungalow (two bedrooms) £180
Mid-floor flat (two bedrooms) £145
The figures are based on a typical gas-heated home. All data has been obtained from the Energy Saving Trust (EST).


2. EWI Improves the thermal comfort

Insulation helps keeping your home warm in winter and cool in summer. It improves thermal comfort by reducing the cold drafts and heat losses through the walls and roof. Your house will maintain a more stable temperature throughout the year providing a pleasant indoor environment to live in.


3. EWI Reduces Thermal Bridges

Thermal bridges occur in parts of the building envelope where there is insufficient amount of insulation and are responsible for up to 35% of thermal losses and increased condensation that leads to mold growth http://www.thegreenage.co.uk/what-is-thermal-bridging/.


4. EWI Reduces the Risk of Condensation and Mould growth

Condensation is caused by the temperature difference between the external and internal surfaces of the walls and windows of your home. EWI helps to reduce the risk of condensation and damp of walls. The top coat renders available for external wall insulation offer an 100% waterproof and hydrophobic protective layer.

Mold growth in domestic houses is also connected with the air temperature and the percentage of humidity inside the house. By providing more insulation to your home the surface temperature of your walls will be higher preventing the risk of mold growth. Mold growth not only deteriorates your house’s condition but is also connected with indoor air quality and health being.


5. EWI makes the construction more durable

There is a number of different insulating renders and finishes available that are especially designed to provide a long lasting, protective barrier on your external walls. External wall insulation (EWI) fills cracks and gaps in the walls and prevents damp of the building envelope offering protection from continuous exposure to cold and rain weather such as in UK climate. Due to the highly durable materials EWI increases resistance against the elements and protects the brickwork remaining the construction at its first condition for more years.


6. EWI makes your house look better

External wall insulation can significantly improve the outside appearance of your home by using a wide range of renders and silicone paints, renders, bricks or tiles. Either your home is old or new, and either it has a Victorian or modern design, the external wall insulation could match excellent to you property maintaining its style and design.


7. EWI Minimizes environmental impact and prevent climate change

UK domestic homes are responsible for 27% of the UK’s GHG emissions, 80% of this is for space and water heating. Therefore, minimising the energy consumed for domestic heating can reduce CO2 emissions and help to prevent climate change. Less fossil fuel consumption will ensure a more sustainable environment for the next generations and less fuel poverty in the future.


To know more about the cost of external wall insulation and the types of insulation materials you can visit our blogs:

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