Insulation Check: How to Tell Your House Is Well Insulated

The UK housing stock is notorious for being one of the most poorly insulated in the European neighbourhood. A 2022 study by the think tank Resolution Foundation (RF) showed that poorly insulated homes burn 58% more gas annually for heating than homes that meet insulation standards. This leads to staggering bills, carbon footprint, and uncomfortable homes.

Insulating your home is a great step, but how can you know if your insulation is functioning properly? Or does your home even have insulation, to begin with? This ultimate guide by GreenMatch UK will give you everything you need to know about insulation checks, including telltale signs of dysfunction, how to take care of insulation, and professional assistance. 

Ready to insulate your home? Let GreenMatch UK be your one-stop solution for all your needs. By filling out our simple 30-second survey, you can get up to 3 free home-tailored quotes from our network of trusted installers. No charges or obligations. Click the button below to begin!

To check if your home is well insulated, there are several things you can keep an eye out for. Generally speaking, the most telltale way to notice a poorly insulated home will be by spotting issues that may be taking place, such as mould growth or condensation.

Here are some tips on what to look out for when checking your home and insulation:

Wondering how to check if cavity wall insulation is wet? Or any insulation for that matter? If you are noticing window and wall condensation in your home or general dampness, this can indicate that there are issues with your insulation, home ventilation or likely both. 

A poorly insulated home with condensation issues can lead to structural rot, and mould growth in your home. Not only does this risk the safety of your home, but damages your health by increasing the risk of respiratory illnesses like asthma. 

If you notice minor mould growth in the shower, that may just be due to the constant exposure to dampness and can be fixed DIY, however, mould growth on walls and living quarters is a very high indicator of insulation issues.

If you wonder how to check insulation in walls, the best way is to pay attention to them. Areas where you can feel a draft, or cold spots on your walls can indicate poor insulation. Drafts indicate panel gaps and openings that need to be sealed, cold spots in walls and floors indicate insulation clumping or areas where the material is too thin. 

Panel gaps and openings can be sealed with plaster or expanding foam, whereas cold spots suggest a more structural issue with your insulation that may need professional help. In most cases, a simple insulation top-up can do the trick. In case the insulation is damaged, it may require a full replacement.

Curious as to why lofts should be insulated, or how to insulate a loft? Uninsulated roofs, lofts and attics are responsible for up to 26% of heat loss in a home, making them big culprits for high energy bills and indoor discomfort. A loft insulation check can ensure that your insulation meets the expected standard.

Look for the depth of your insulation, especially if you have a cold loft insulation job (i.e. your loft floor contains insulation). This material should normally be at least 270mm deep for optimal performance. If not, it requires an insulation top-up to meet the required standards.

Perhaps one of the most telltale signs of dysfunctional insulation is sudden unexplained increases in your energy bills. By comparing your monthly and yearly consumption and costs, do you notice a drastic change?

If so, this increase can indicate that there is something wrong with your insulation and it is no longer insulating your property effectively. Contacting a professional for an insulation inspection would be the best step to take from here to identify the exact problem. 

Each insulation material has an r-value, a quantifiable measurement that shows how effective a material is in resisting heat transfer. Materials have ideal r-values at their most optimal condition. 

By arranging a professional insulation inspection, you can check to make sure your insulation is as effective as it should be. If the r-value indicates is much lower than the optimal function, it might mean your insulation is damaged or in poor condition.

The age of your property can give clues as to when was the last time your home was insulated. The general lifespan of each insulation material may be different, it’s a rule of thumb that insulation should be inspected and topped up every 15 to 20 years. 

Insulation that is left uninspected for longer than 20 years may have lost its efficiency, become damaged, or experience issues such as clumping, moisture and mould growth. This insulation would need to be completely removed and replaced.

In most cases, the poor function of insulation in your home will become apparent from the issues your home is experiencing. Problems such as excessive condensation and moisture, persistent mould, drafts, and cold spots all identify that something isn’t working as it should.

In these cases, the existing insulation material will almost always need to be removed and replaced, which in itself is a very costly process. Luckily, the UK government backs two grant schemes that can assist with full or partial funding for qualifying homes.

The Great British Insulation Scheme (GBIS) and the Energy Company Obligation (ECO4) both provide home upgrades to low-income and fuel-poor households. To apply for a home insulation grant from the GBIS, you can visit the official UK website and fill out an application form. For the ECO4, contact your energy provider to learn more.

While durable and professionally installed insulation can sometimes last upwards of 80 - 100 years, it’s a rule of thumb that insulation should at least be inspected every 15 to 20 years.

That way, insulation issues can be identified and addressed proactively, before they become much larger issues and cause structural damage to your home. 

By arranging an insulation expert to inspect your home every 15 or so years, even in the absence of problems, you can be one step ahead of maintaining your home's comfort.

Whether you can conduct a DIY insulation check or require a professional depends on several factors, such as the type of insulation in question, and where it is installed.

For example, loft insulation such as mineral wool or loose fill can generally be checked DIY and even topped up, but injected cavity wall insulation will almost always need a professional. Nevertheless, conducting a free insulation check with an accredited installer can bring about lots of benefits, such as:

With all things considered, finding the perfect installer can sometimes feel like looking for a needle in a haystack. Prospective customers often find themselves stuck in an endless cycle of surfing websites and scheduling phone calls with no deal in sight. GreenMatch UK can fix that.

By filling out our simple 30-second online form, you can receive up to 3 free home-tailored quotes from our network of pre-vetted installers throughout the UK. No charges or obligations apply. Just click the button below to begin!