Why Victorian Homes Need Breathable External Wall Insulation
- Tim Gjana
- Jul 31
- 4 min read
Updated: Aug 8
When it comes to insulating period properties, particularly those built before 1920, the question is not just how to insulate, but how to insulate without compromising breathability and heritage features. For homeowners living in classic London homes, breathable external wall insulation (EWI) is fast becoming the go-to solution. Not only does it maintain the character of older buildings, but it significantly improves energy efficiency without trapping moisture, a common issue in solid brick walls.
To get a free quote today from TNK Construction,
call us on 020 8128 9485, or email info@tnkltd.co.uk.
Understanding Breathable External Wall Insulation
Breathable external wall insulation refers to a specific type of EWI system designed to allow moisture vapour to pass through the building fabric, rather than becoming trapped inside the walls. For older homes, especially those built with solid brick or lime mortar, this is critical. Modern, non-breathable systems can seal moisture in, leading to mould, damp, and even structural damage over time.
These breathable systems typically consist of:
Wood fibre or mineral wool insulation
Lime or silicone-based renders
Vapour-permeable membranes and adhesive layers
These materials work in tandem to protect the property from weather while letting internal moisture escape naturally.
Why Breathability Matters in Victorian Homes
External wall insulation for Victorian homes requires a considered approach. Victorian properties, which dominate many London boroughs like Islington, Camden, and Kensington, were built with solid walls that ‘breathe’. Blocking this breathability with impermeable systems causes moisture to accumulate, compromising structural integrity and occupant health.
At TNK Construction, we have completed dozens of projects that blend conservation sensitivity with modern performance. One notable example is a Victorian home refurbishment in Islington, completed ahead of schedule. Our team restored sunken floors, preserved cast-iron features, and installed insulation with breathable lime render, achieving a warm, dry, and energy-efficient result without losing the building’s charm.
The Role of ECO4 Grants and Why Timing Matters
Applying for EWI funding through the ECO4 scheme can significantly reduce your costs. This government initiative provides financial support to homeowners seeking to improve energy performance. However, the scheme is time-sensitive, budget-limited, and subject to eligibility criteria.
So, when is the best time to apply for EWI grants?
Right now. With net-zero targets intensifying, demand for grants is at an all-time high. TNK Construction not only installs ECO4-compliant breathable external wall insulation, but also supports clients with the paperwork and application process.
Delaying may mean missing out on key funding opportunities. TNK's streamlined consultation and proposal process ensures your project is grant-ready quickly and accurately.
Read more on ECO4 grants and eligibility here.
Why Choose TNK Construction for External Wall Insulation?
Founded by Tim Gjana, TNK Construction brings over 17 years of experience in London’s most sensitive and sophisticated builds. From period refurbishments in Hampstead to six-flat installations in Richmond, our team knows how to deliver external wall insulation that respects heritage while meeting modern standards.
Our three-stage process ensures peace of mind:
Initial Assessment – Site visit, consultation, and bespoke proposal
Construction Phase – Precise planning, quality build, and expert coordination
Post-Construction – Final inspection, full handover, and responsive aftercare
Our workforce is CITB-accredited and deeply familiar with breathable wall insulation materials suitable for solid wall and heritage homes. In every project, we prioritise attention to detail, from parge coatings to vapour-permeable adhesives.
View the Richmond flats project or read our Islington transformation case study for proof.
External Wall Insulation vs Internal Insulation: What's Best for Victorian Homes?
While both approaches aim to improve thermal efficiency, external wall insulation is almost always the better choice for older properties.
Why?
It preserves interior space
It protects external walls from weather
It improves airtightness without sealing in moisture
It avoids interfering with ornate interior features such as coving, fireplaces, and original plasterwork
Internal wall insulation often creates cold bridges and can lead to internal condensation unless installed with extreme care. For London homes where every square foot counts, external solutions are more practical.
Common Misconceptions About Breathable Insulation:
“It won’t be as energy efficient” – Modern breathable materials have excellent thermal performance and comply with PAS 2035 retrofit standards.
“It will ruin the look of my house” – TNK uses render systems that blend perfectly with Victorian exteriors, including lime-based finishes and coloured silicone renders to match surrounding buildings.
“It’s too expensive” – With ECO4 grants and long-term energy savings, breathable EWI is a smart investment.
Follow us on Instagram for more insights, team stories, and build updates.
Our Commitment to London Homeowners
Whether you live in a conservation area or simply want to maintain your home's original features, TNK Construction offers tailored insulation solutions that respect your home’s identity. Our work in Islington, Richmond, and Hampstead reflects a deep understanding of both construction and heritage sensitivity.
From bespoke chimney designs to integrated wardrobes and breathable insulation upgrades, our team delivers projects that are functional, beautiful, and built to last.
Ready to Retrofit Your Victorian Home?
Let TNK Construction guide your grant application and deliver a breathable external wall insulation system tailored to your property.
Call 020 8128 9485 or email info@tnkltd.co.uk to book your free consultation.
FAQ: Breathable External Wall Insulation for Victorian Homes
1. What is breathable external wall insulation?
Breathable EWI is an insulation system designed to allow moisture vapour to pass through the wall, helping to prevent damp issues in older homes with solid walls.
2. Why do Victorian homes need breathable insulation?
Victorian properties were built with materials like lime mortar that naturally allow moisture to escape. Breathable EWI protects these properties without sealing in damp or causing structural damage.
3. Can I get a grant for external wall insulation in 2025?
Yes. Under the ECO4 scheme, homeowners who meet certain criteria can apply for funding. TNK Construction can help determine your eligibility and guide you through the process.
4. Does breathable insulation affect the appearance of my home?
No. At TNK, we use renders and finishes that match the original look of your property, preserving kerb appeal and aesthetic value.
5. How long does the installation process take?
Most EWI projects take between 2 to 4 weeks, depending on property size and complexity. TNK provides clear timelines in the initial proposal.