TrustMark Registered · BBA-Approved Systems
External Wall Insulation & Rendering in Coventry, the Midlands & London
If your home was built before 1919, its walls are almost certainly solid – there’s no cavity to fill, and around 33% of all heat lost from an uninsulated home goes straight through them (Energy Saving Trust). External wall insulation fixes insulation boards to the outside of those walls and finishes them in a weatherproof silicone render, bringing a typical solid wall from around 2.1 W/m²K down to 0.30 or better – the standard set by Building Regulations Part L.
25-year insurance-backed guarantee
A warmer home, lower heating bills and no more cold walls
TrustMark registered - Licence No. 3752723
Self-cleaning silicone render in a wide range of colours
Windows, doors and garden protected - we leave the site spotless
Trusted by Hundreds of Homeowners Across the Midlands and London
4.7 ★ based on 63 reviews
4.8 ★ based on 49 reviews
5.0 ★ based on 14 reviews
4.7 ★ based on 63 reviews
4.8 ★ based on 49 reviews
5.0 ★ based on 14 reviews
4.7 ★ based on 63 reviews
4.8 ★ based on 49 reviews
5.0 ★ based on 14 reviews
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. 
Trustindex verifies that the original source of the review is Google. External Wall Insulation Before & After
Four recent projects in Coventry, Birmingham, Leicester and Bedford - solid walls insulated and finished in silicone render.
Drag each slider to compare.
Coventry
Red Brick Terrace
Cold solid brick walls with no cavity
✓ 100mm EPS insulation boards
✓ Kabe silicone render
✓ 25-year insurance-backed guarantee
Birmingham
Pebbledashed Detached
Tired pebbledash over an uninsulated solid wall
✓ Pebbledash covered and walls insulated
✓ Silicate-silicone render finish
✓ Improved EPC rating and weather protection
Leicester
Stained Side Elevation
Algae staining and streaking on an exposed elevation
✓ Solid wall insulation system
✓ 1.5mm coloured silicone render
✓ Algae-resistant finish - no more black streaking
Bedford
Damp-Stained Walls
Staining at the base and cold bridging at the edges
✓ Insulation carried to the edges to stop cold bridging
✓ White Kabe render topcoat
✓ Contrasting protective plinth at ground level
Our Services
Insulated Render Installation & Repairs for Domestic & Commercial Properties
PD Rendering has insulated and rendered more than 750 homes across Coventry, the Midlands and London since 2014.
Chosen and installed correctly, an insulated render system cuts heat loss, reduces condensation and damp, and gives the building a completely new exterior.
External Solid Wall Insulation
Insulation boards fixed to the outside of your walls, in graphite EPS or mineral wool, and finished in silicone render.
✓ Lower heating bills and warmer rooms
✓ Eliminate damp and condensation
✓ 25-Year insurance-backed guarantee
High Performance Render Systems
Upgrade your home's exterior with durable, weather-resistant rendering. We offer a wide range of colours and finishes to suit your style.
✓ Self-cleaning silicone technology
✓ Breathable & weather-resistant
✓ Little maintenance and no repainting
Insulation & Render Repairs
Notice signs of wear, cracking, or damage on your existing render? Our maintenance team restores both the functionality and beauty of your walls.
✓ Professional crack repairs
✓ Patching and colour matching
✓ Preventative maintenance
Is External Wall Insulation Worth It?
Where Your Heat Goes, and What Insulation Changes
Walls are the single biggest source of heat loss in most solid-wall homes. Insulating them is one of the most effective ways to cut heat loss and improve an EPC rating.
"Around 33% of all heat lost in uninsulated homes escapes through the walls. By insulating your solid walls, you could save energy, lower your heating bill and make your home more comfortable." - Energy Saving Trust
Energy Savings
Insulating solid walls keeps that heat where it belongs - warmer rooms and heating that runs less often.
25-Year Guarantee
Total peace of mind with our comprehensive, 25-year insurance-backed guarantee on materials and labour.
Approved Installers
TrustMark registered and working to PAS standards. Our own teams, on every job - never subcontracted labour.
Value Increase
A completely new exterior in the colour and finish you choose, and a better EPC rating when it comes to selling or letting.
How it Works
How External Wall Insulation is Installed, Step by Step
From the first survey to handing over your guarantee - here is what happens on site, and how long each stage takes.
Free Consultation
We visit your property to measure, discuss your needs, and provide a transparent, no-obligation quote. No hidden costs.
Usually within 7 days of your enquiry
Design & Prep
You choose your perfect colour and finish. We set up safely, carefully protecting your windows, doors, and garden.
Quote provided in 3-7 days;
work starts 2-4 weeks after sign-off
Expert Installation
Our TrustMark registered team installs the insulation and render system, typically over 2 to 4 weeks, with minimal disruption to your daily life.
Typically 2-4 weeks;
up to 20 working days for larger detached homes
Final Sign-Off
We leave your property spotless. We hand over the 25-year guarantee only when you are 100% satisfied with the result.
Immediate upon project completion
Areas We Cover
Serving the Whole of the Midlands and Greater London
We provide expert solid wall insulation and silicone rendering within a 70-mile radius of Coventry, with a dedicated team serving Greater London.
Not sure if we cover your postcode? While we focus on our core regions, we regularly take on larger projects further afield. Contact us with your project details, and we’ll happily see how we can help.
Insulation & Render Guides
External Wall Insulation and Rendering, Explained
Straight answers on costs, materials, EPC ratings and what to expect from an insulated render system.
5 Common External Wall Insulation Mistakes to Avoid
External wall insulation offers many benefits, from lower energy bills to a more comfortable home. However, the benefits only
External Wall Insulation: What’s the Difference Between EPS and Mineral Wool?
External wall insulation is one of the most effective ways to reduce heat loss, cut energy bills, and make
External Wall Rendering: Types of Materials and Finishes for UK Homes
Explore the most popular external wall rendering finishes in the UK, including a range of styles, textures, and materials.
Is External Wall Insulation Worth It?
External wall insulation can significantly improve your home’s energy efficiency and comfort - but is it really worth the
External Wall Insulation for Semi-Detached and Terraced Homes
Learn how external wall insulation works for semi-detached and terraced homes, including its key benefits and what to consider
How Much Does it Cost to Render a House?
Planning rendering work on your house? Learn what affects the price, your finish options, and how to compare quotes
10 EWI & Rendering Projects in the Midlands and Beyond
Real project examples of EWI and render upgrades carried out across the Midlands and London, improving energy efficiency, protection,
Can You Stay at Home During External Wall Insulation or Rendering Works?
Learn how the process works and what level of disruption to expect.
Render Looking Tired? What Causes Cracks, Stains & Green Growth
Learn what causes cracks, stains and algae on external render, how to spot serious issues, and when to repair
Does External Wall Insulation Cause Damp? Risks & Prevention
Learn the real causes of damp after EWI, common risks, and how to prevent moisture issues in your home.
Common Questions
External Wall Insulation and Rendering – Your Questions Answered
Got questions about EWI or silicone rendering? We’ve compiled the answers to help you make an informed decision for your property.
How much does external wall insulation cost?
Cost depends on wall area, access, the system specified and the finish you choose – a mid-terrace and a detached house with three exposed elevations are very different jobs.
As a guide:
- £10,000-£14,000 for a mid-terrace
- £14,000-£18,000 for a semi-detached
- £18,000-£24,000 for a detached house, at 0% VAT.
The insulation and render system itself works out at around £85-£90 per square metre; scaffolding and any repositioning of gutters, downpipes and sills is itemised separately on your quote rather than buried in a square-metre rate.
Silicone rendering without insulation is roughly £60-£70 per square metre and is standard-rated at 20% VAT.
Is my home suitable for External Wall Insulation (EWI)?
Most UK homes built before 1919 have solid walls with no cavity to fill.
These are ideal candidates for EWI, because a solid wall lets a lot of heat straight out.
If you’re unsure, our team can identify your wall type by examining the brickwork pattern during a free survey.
Does external insulation really stop damp and mould?
Yes – for condensation damp, which is the most common kind. EWI moves the “dew point” to the outside of the wall.
That removes the cold surfaces where condensation forms, which is what allows mould to grow.
Your home will be warmer, drier, and much healthier.
Damp caused by rising moisture, failed guttering or leaks needs fixing separately – we check for this at the survey.
Will I need to leave my home during the installation?
No. All works are carried out on the exterior of the property.
Disruption is minimal and there is no need to move out while the work is done.
How long does the EWI installation process take?
The installation itself typically takes 2 to 4 weeks (or up to 20 working days for larger detached homes).
However, for your peace of mind, here is what the timeline for the entire project usually looks like:
- Survey:
We aim to visit your property within 7 days of your enquiry. - Quote:
Provided 3-7 days after the survey. - Start Date:
Work usually commences 2-4 weeks after you sign off on the quote.
Please note that external insulation and silicone rendering are weather-dependent processes. We require dry conditions to ensure the materials bond and cure perfectly, guaranteeing our 25-year lifespan.
What is the difference between Grey EPS and Mineral Wool?
Grey EPS (graphite polystyrene) gives more thermal performance per millimetre, so it needs less thickness to reach the same U-value. On solid brick it is usually the most cost-effective choice.
Mineral wool is non-combustible (Euroclass A1) and more vapour-open, so it suits older “breathing” construction and any building where fire performance is the priority. It needs slightly more thickness for the same U-value.
We specify whichever suits your wall type, exposure and fire requirements, and confirm the U-value calculation before work starts.
Do I need to prepare my walls before the installers arrive?
For the best results, walls should be cleaned of dust and loose material.
However, part of our professional service includes a thorough assessment and preparation of the surface to ensure the insulation materials bond perfectly to your specific wall type.
Can I insulate just my half of a semi or terrace?
Yes, external wall insulation can be installed on just your property.
On a mid-terrace, it is typically applied to the front and rear elevations. On a semi-detached or end-terrace, it also covers the exposed gable side. Where the system meets a neighbour’s wall at the boundary line, our installers form a sealed stop using uPVC stop beads, mesh reinforcement and high-quality sealant. This prevents water ingress and avoids any overhang onto the neighbouring property.
You can find more details in our guide: External Wall Insulation for Semi-Detached and Terraced Homes.
Will EWI drastically change the look of my property?
It’s more of a refreshment than a radical change, though it can completely modernise an older building.
We offer a wide variety of Silicone Render colours and finishes, allowing you to either replicate the original look or create a brand-new aesthetic for your home.
How much can I actually save on energy bills?
Around 33% of all heat lost from an uninsulated home escapes through the walls (Energy Saving Trust), so insulating them removes the single biggest source of loss.
Exactly how much you save depends on your property, how you heat it and how warm you keep it. Many households take part of the benefit as a warmer home rather than a lower bill.
We give you a realistic figure for your property at the free survey.
Do I need planning permission for insulation work?
In most cases, EWI falls under “Permitted Development.”
However, if your property is in a conservation area or the aesthetic change is significant, permission may be needed.
We provide expert guidance and help you navigate these local requirements.
Can EWI be installed on non-traditional constructions?
Yes. EWI works on a wide range of non-traditional constructions, including concrete panel systems, steel-framed and no-fines properties.
These homes are often among the coldest and hardest to heat, so insulating them externally is usually the single most effective improvement available.
The fixing method and board specification are set at the survey to suit the substrate.
What exactly is the "25-Year Guarantee"?
A 25-year insurance-backed guarantee backs every system we install. This covers both materials and workmanship, ensuring your investment is protected long-term.
Does the insulation require any maintenance?
Our silicone renders are self-cleaning and weather-resistant, meaning they require very little maintenance.
The system is designed to be breathable and durable, preventing cracks and keeping your facade looking fresh for years without repainting.
Get Your Free Quote
Leave your details and we'll get back to you within one working day, usually the same day.
Phone
Address
Unit L, 34 Bayton Rd, Exhall, Coventry, CV7 9EJ, United Kingdom.
No hard sell. We'll arrange a survey at a time that suits you, and
you'll get a fixed written quote with no obligation.
No hard sell. We'll arrange a survey at a time that suits you, and
you'll get a fixed written quote with no obligation.
Phone
Address
Unit L, 34 Bayton Rd, Exhall, Coventry, CV7 9EJ, United Kingdom.