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External Wall Insulation

Ewi information 

Adding insulation to your home can be done on one of three ways – internally, within the cavity or externally.
If you live in a solid wall property or a non-traditionally constructed house then cavity insulation is not or may not be an option. In addition, your preference may not be to insulate internally because of the loss in living space this will result in (not to mention the cost of moving fitted furniture and redecoration). For these reasons external wall insulation system may be your preferred option.
Ive put together a short external wall insulation or EWI guide  to answer the basic questions we are commonly asked.

The Benefits of External Wall Insulation
As a homeowner, the benefits of thermally upgrading your home using external wall insulation are significant –the main benefits are as follows:
    •    Improves thermal performance
    •    Reduces carbon footprint
    •    Energy bills drop
    •    Thermal comfort improves
    •    Adds acoustic insulation
    •    Reduces condensation and damp  property
    •    Protects the existing fabric
    •    Adds value to your property

EWI  Planning Permission And Regulations
In most cases you won’t require planning permission from your local council to install an EWI system to your home. 
However, if you live in a listed building, if you’re in a conservation area or if the thickness of the insulation you’re proposing infringes into someone else’s land or a public walkway or road you will require permission. 

Can EWI Be Used On Any Property

EWI is a highly effective way of thermally upgrading a property which can be used on many properties and most construction types … but not all. It’s not the appropriate solution in every case so it’s vital that each project is assessed by an EWI system manufacturer or contractor first prior to

specifying The Right External Wall Insulation System

I will organise for your property to be surveyed in order that the correct EWI system can be specified.
The system will depend on the property and your own requirements. The insulant will typically be EPS or mineral fibre with a thickness depending on the thermal improvement you’re looking to make and the options for how think the insulation can be compared to existing overhangs and without infringing on other properties.  Fixings will be dependent on the thickness of insulant and the substrate they will be fixed in to and the finish effect, texture and colour will be down to personal preference. 

How Will My Property Look?
A tired looking, cold and expensive to heat property can be completely transformed into a warm, energy efficient and stunning looking home. 
As for colour, modern renders are designed for EWI systems and often come ready mixed and through colour with a choice of lots of different colours.
You can design the finish to ensure your property looks exactly the way you want it to and completely transform it if you wish. 


As for benefits … by installing EWI you can expect a reduction in energy usage of up to 40% and the Energy Savings Trust estimate a saving of up to £455 per year (prior to the 2022 energy price rises).
In addition to annual savings on energy the value of your property should increase by an average of £10,000 (in England) due to the improved EPC rate and the aesthetics.
How Long Does It Take To Install EWI?
This really depends on your property and the system being installed.
By way of a guide, it starts with a survey prior to works commencing. This checks for things such as:
    •    Suitability of the existing wall for mechanical fix – this will consist of a pull-out test.
    •    Reveals, windows and doors to check for any issues
    •    Overhang on cills, soffits and such like
    •    What will need to be taken down and re-fixed – satellite dishes, meter boxes, gates etc
    •    Soil pipes which may need to be moved
    •    Any existing coating which will affect the adhesion of the system
Any issues identified will first need to be addressed as part of the preparatory works.
Once the substrate is prepared there are three main stages to the actual works:
    1.    Boarding and beading: on an average size property this will take up to two days
    2.    Basecoat and reinforcing mesh: This will take a couple of days to apply with a further drying time of up to 72 hours
    3.    Top coat or finish: This completely depends on the finish selected – anything from a single day (for a basic thin coat render).
We have put together a short, generic EWI Installation Guide to explain the process in more detail.
Scheduling The EWI Installation
There are certain weather-related restrictions when it comes to installing an EWI system. Render should not be applied in temperatures of 5 degrees and falling, not should they be applied in direct sun when the temperature is too high (usually around 25 degrees plus).
Wet weather can also present a problem so you may want to consider sheeting scaffolding to add protection from the elements and even adding heaters depending on the time of year and conditions.
How Long Will EWI Last?
EWI is a long-term investment. Most system designers will be able to provide a warrantee of, or in excess of 10 to 15 years.
No EWI system is maintenance free but all are described as low-maintenance. Whilst renders and finishes are through coloured and won’t require painting, they will always benefit from a gentle power-wash periodically in order to remove dirt and airborne pollutants.
 specify the optimum system, provide an accurate quotation and guide you through the process without obligation:

External Wall Insulation System 

There are so many different types of projects, and that's why I make sure to discuss every detail with you before beginning so you know exactly what to expect, and exactly how much it’s going to cost.

External Wall Insulation: Services
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