A Guide to Insulation

How to Insulate Your Home for Comfort, Energy Savings, and Sustainability

Did you know that millions of homes in the UK lack proper insulation? Despite our chilly climate for most of the year, many houses still allow heat to escape—leading to higher energy bills, unnecessary carbon emissions, and uncomfortable living conditions.

If you want a warmer home in winter, a cooler home in summer, and lower energy costs, insulation is the key. Let’s explore why insulation matters, how to choose the right type for your home, and the best ways to install it.

Why Insulating Your Home is Essential

A well-insulated home provides year-round comfort by creating a thermal barrier between the inside and outside of your property. This means:

• Lower energy bills – Less heat escapes in winter, reducing the need for excessive heating.

• Reduced carbon footprint – Using less energy helps cut down on CO₂ emissions.

• Improved indoor comfort – No more cold drafts or hot, stuffy rooms.

• Moisture control – Proper insulation helps prevent dampness and mould.

By investing in quality insulation, you’re not just improving your home’s efficiency—you’re also increasing its long-term value.

Choosing the Right Insulation for Your Home

The right insulation depends on your property’s age, construction type, and moisture management needs. Here’s a breakdown of the best insulation options for different home types.

Cavity Wall Construction

For homes with cavity walls, insulation can be installed in multiple ways:

• Cavity wall insulation – Filling the space between the inner and outer walls with materials like mineral wool or foam.

• Internal insulation – Adding insulation boards inside the home.

• External insulation – Fixing insulation panels to the outside of the walls, then covering them with a protective render.

Solid Wall Construction

Older homes with solid walls constructed of Brick, Stone, Clay, and Lime require insulation that maintains moisture balance. These materials allow walls to "breathe," reducing the risk of trapped moisture:

• Wood fibre boards

• Cork boards

• Lime-based insulating plasters and renders

• Other hygroscopic materials (vapour-open insulation)

For solid walls, consult a professional to assess thermal efficiency using WUFI modelling, which helps determine moisture risks before insulating.

How to Ensure Proper Insulation Coverage

To maximise energy efficiency, your home’s insulation should be continuous, covering all key areas like roofs, walls, floors, windows, and doors.

Roof & Loft Insulation – The Number One Way to Cut Energy Bills

Around 25% of a home’s heat escapes through the roof, loft insulation is one of the most cost-effective upgrades. A thick layer of insulation at the ceiling level keeps warm air in during winter and prevents overheating in summer. Recommended materials: Sheep’s wool, mineral wool, rigid foam boards or wood fibre boards.

Wall Insulation – Keeping the Heat Where It Belongs

Walls account for around 35% of heat loss in an uninsulated home. Depending on your home’s construction type, you can use:

• Internal wall insulation (IWI) – Best for solid walls, using insulation boards or insulating plaster.

• External wall insulation (EWI) – A layer of insulation applied to the outside of your home.

Important: In areas with heavy wind-driven rain, IWI may not be the best option—seek professional advice.

Floor Insulation – Preventing Cold from Below

Insulating your floors helps maintain consistent indoor temperatures. If your home has a suspended floor, insulation can be placed beneath the floorboards. For solid floors, a thin layer of insulation on top will still make a noticeable difference. Insulate areas above unheated spaces (like garages or basements) to further reduce heat loss.

Windows & Doors – Sealing Air Leaks for Extra Efficiency

Even the best insulation won’t be fully effective if warm air leaks through windows and doors. Improve performance by:

• Installing high-performance windows (if replacing them is an option).

• Adding weatherstripping and caulking to seal gaps.

• Using airtightness tapes internally to reduce air leakage.

Avoiding Common Insulation Mistakes

To get the best results, avoid these common insulation errors:

• DON’T: Ignore thermal bridges – Areas like internal wall junctions, window & door reveals, and floor voids can create cold spots, leading to condensation and mould.
  DO: Ensure continuous insulation coverage and address weak points.

• DON’T: Use the wrong materials – Not all insulation works for every home type.
  DO: For older solid-walled homes, always use vapour-open, breathable materials to avoid trapped moisture.

• DON’T: DIY installation errors – While loft insulation is a common DIY project, insulating walls improperly can cause problems to your building fabric.
  DO: Hire a professional to design and install complex insulation work.

Final Thoughts: Is Insulation Worth It?

Absolutely! Investing in the right insulation will:

• Lower your heating and cooling costs

• Improve your home’s comfort and indoor air quality

• Reduce your environmental impact

By taking a whole-house approach to insulation—covering your roof, walls, and floors, and sealing air leaks—you’ll enjoy a warmer, more sustainable home for years to come.

What’s Next?

• Thinking about insulating your home? Consult a professional to find the best materials for your property.

• Want to learn more? Check out our guide on Energy-Saving Tips for UK Homes.

• Got questions? Drop a comment below—we’d love to help!