Improve energy efficiency at home with flat roof insulation.
If heat loss and a general lack of cosiness is an issue around your home, introducing flat roof insulation could hold the key. While we don't offer financial support for flat roof insulation at the moment, we believe in its potential to make homes like yours more energy efficient.
But we’re not here to pressure you into a decision. Instead, read our honest, straightforward advice about flat roof insulation, so you can decide for yourself.
What is flat roof insulation?
If you’re new to insulation, the term ‘flat roof’ insulation might have you scratching your head. It basically involves adding a thermal barrier to a flat or nearly flat roof (think pitches below 10°) to make it more energy efficient.
This type of insulation helps to keep heat where it should be – inside in the chilly winters and outside in the sweltering summers. It’s also worth noting that flat roofs have a bigger surface area than pitched roofs, making them more prone to heat loss.
What are the benefits of insulating a flat roof?
Don’t just see flat roof insulation as a barrier against the cold; see it as a smart investment that could boost your home's energy efficiency and comfort factor. Let’s take a look at some of the other potential perks.
Potential cost savings.
Did you know that up to 25% of the heat generated in your home is lost through warm air rising and escaping through your roof? Stopping that heat from leaking outside could reduce your energy bills and carbon emissions.
Remember, better insulation means that your heating and cooling systems won't need to work as hard, which could benefit your wallet and the planet.
Comfort all year round.
Picture a well-insulated roof like a cosy blanket, keeping your home warm in the winter. However, in the summer, it works in reverse, preventing heat from getting inside. So, your rooms are cooler and more comfy – ideal in a heatwave!
Reduce condensation and dampness.
Without proper insulation, warm, moist air can hit a cold roof and turn into condensation. Over time, this can lead to damp patches, mould growth, structural damage, you name it! Happily, insulation helps to control situations like this, keeping your roof and your home healthy.
Extend your roof’s life.
If the temperature swings from hot to cold over a long period, it could put extra stress on your roof's structure and waterproofing. Insulation acts as a shield, protecting your roof from these changes and potentially extending its shelf life.
Though repairs at one stage or another are possible, having tough insulation could see you calling the repair company much less often.
Your EPC rating and carbon footprint.
Homes with well insulated roofs usually have a better Energy Performance Certificate (EPC) rating. And a higher EPC rating can be more attractive to potential buyers, which could help sway them with their decision making.
Plus, by reducing the energy needed to heat your home, you could also lower your carbon footprint. Opting for more sustainable insulation materials, like those with recycled content or natural fibres, helps to support eco friendly building practices.
How much does flat roof insulation cost?
Now we’ll dive into the financial side of things – though exact costs are dependent on your home and needs.
How much could it cost you?
There isn't a set figure, but typically, flat roof insulation could set you back between £30 and £35 per square metre. The average total for roof installation cost can range from £740 to £1,700. Of course, this all depends on the size of your roof, the materials you choose, and the complexity of the job.
What could you save in the long and short term?
The Energy Saving Trust estimates that a typical semi detached home could save around £230 per year on heating bills by having 270mm first time loft insulation installed. For a detached house, savings could be even higher – potentially around £390 per year.1
While the upfront costs might seem a lot, the payback period could be fairly quick. Lower energy bills, improved comfort, and a boost in your home’s EPC rating could mean a solid long term return on your investment.
What are the different types of flat roof insulation?
Thought there was just one way of insulating flat roofs? You might be surprised to find out there isn't just one way to do it. However, the method depends on the structure of your home and your specific needs. The two main systems are warm roof and cold roof, but there are some other options to consider, too.
Warm roof.
Warm roof is the most common insulation method. The insulation is placed on top of the roof deck – but below the waterproof membrane. This process keeps your roof’s structure warm, helping to reduce potential condensation. Be aware that it can raise the height of the roof, potentially affecting things like guttering.
Cold roof.
Then there’s cold roof insulation. This is when insulation is fitted between your roof’s joists with a ventilated air gap above. The main challenge here is that the roof deck remains cold. You’ll also need to ensure there’s enough ventilation to stop condensation and moisture problems.
Inverted roof.
This is when the insulation is placed above the waterproofing layer and held down with a layer of ballast (like gravel or paving slabs). This process protects the waterproof layer from thermal stress and UV rays.
Tapered insulation.
With tapered insulation, a gentle slope is created on the flat roof, helping to drain rainwater efficiently, which helps prevent standing water and leaks. It's often used in combination with other insulation types to boost drainage.
Green roof systems.
Finally, there are green roof systems, combining insulation with a layer of living vegetation. Together, it adds extra thermal mass, manages stormwater, and boosts biodiversity.
What other types of insulation are available?
We don't currently offer or install flat roof insulation at the moment, but there are other insulation options available that you could get for a free or discounted rate. Many of these opportunities are discounted or completely free to you through initiatives like the Great British Insulation Scheme (GBIS) and other government schemes. Let’s take a look at your options.
Cavity wall insulation.
Homes built in the last 80 years or so likely have cavity walls. This is when your external walls are made of two "skins" – an inside and an outside wall – with a handy gap, or cavity, in between them. Cavity wall insulation fills that gap with insulating materials. Cavity wall insulation is free to you through the GBIS.
Loft insulation.
Just like flat roof insulation, loft insulation helps to stop heat escaping through your roof in the winter and keeps it out in the summer for a cooler home. Learn more about the discounts available to support loft insulation projects.
Room in roof insulation.
Rooms in roof spaces can lose heat if they’re not insulated properly. The process involves fitting insulation boards between the rafters of attic conversions or loft rooms, creating a thermal barrier that helps to reduce heat loss. Find out more about room in roof insulation and the support up for grabs.
Installing your flat roof insulation.
Safe and proper installation is just as important as the materials you choose for your flat roof. Let’s review some of the key things you should consider when it comes to installation, from best practices to common mistakes.
Best practices.
Before the work gets going, there are several things you should consider to make the process a smooth one:
- Inspect and repair your roof before work gets underway.
This involves ensuring the insulation system is compliant with building regulations, usually aiming for a U-value of 0.18 W/m²K or better. On the other hand, if your roof is completely flat, get tapered insulation to help with drainage.
- For more complex projects, don't struggle.
Get the help of a professional installation company. They'll be able to come up with the best solution for your home.
- Protect your investment and extend roof life with regular maintenance.
Once your insulation is in, you’ll need to organise regular inspections of your roof to check for leaks, damp, and damage.
Common mistakes.
Finally, there are some of the most common mistakes to look out for when installing flat roof insulation. The main culprits include:
- Not using enough material.
- Not providing proper ventilation (a big mistake for cold roofs).
- Skipping the vapour control layer.
- Not addressing drainage issues (possibly leads to pooling water and leaks).