Creating warm a loft space with Celotex PIR insulation
When couple Eve and Ty started hunting for their dream home near Manchester, they didn't expect to go viral on TikTok. But that's exactly what happened when their ambitious project caught the attention of millions (15 million views and counting, to be exact).
U-value Calculator
Start your U-value calculationUsing Celotex’s U-Value calculator and GA4100 PIR insulation boards to create a warm loft space. Find out how.
| Products Used: | Celotex GA4000 |
|---|---|
| Sector: | Housing |
When couple Eve and Ty started hunting for their dream home near Manchester, they didn't expect to go viral on TikTok. But that's exactly what happened when their ambitious project caught the attention of millions (15 million views and counting, to be exact).
One of the biggest challenges came when they decided to raise the roof and transform the loft into a new bedroom, ensuite and laundry room. The couple needed to achieve specific thermal performance levels while keeping every inch of usable space. No small feat when you're managing the project yourself.
This is where Celotex’s U-Value calculator and GA4100 PIR insulation boards played a role, ensuring the necessary thermal performance while complying with Building Control standards.
How did the Celotex U-value calculator help Eve and Ty choose the right insulation?
When Eve and Ty found their home in Bramhall, a village just outside Manchester, the survey revealed a major challenge: the roof needed replacing. So inspired by a friend’s renovation, they decided to raise the roof (literally) and transform the loft into a new bedroom, ensuite and laundry room.
They approached the project methodically, deciding to create a carefully layered insulation system using PIR insulation boards between the rafters. This was alongside adding external insulation to further enhance thermal control, and mineral wool in the walls to reduce heat transfer.
To make sure they got the specs just right, Eve and Ty turned to Celotex’s U-value calculator to determine the exact insulation thickness required to meet Building Regulations while maximising thermal efficiency.
They started the roof work in June 2023, just before the 2024 changes to Part L of Building Regulations. This meant their roof insulation had to be a U-value of 0.18 W/m²K for thermal efficiency. Using the Celotex U-Value calculator, they were able to determine that Celotex GA4100 PIR insulation boards would provide the necessary thermal performance while maximising space.
“The Celotex U-value calculator really helped us to get to grips with exactly what we needed for our project,” Eve said. “Even if your builder is doing the calculations, I’d definitely recommend using the U-value calculator to double check everything.”
As the couple shared their journey on social media, many of their followers got in touch about the process. “It was great to be able to show people how it’s possible to achieve results with tools like the Celotex U-value calculator, even if they're not seasoned professionals,” Eve said. “I loved seeing lots of women get in touch too to say they were inspired to try these projects themselves.”
Why did Eve and Ty end up choosing Celotex GA4100 PIR insulation boards?
In the end, the U-value calculator helped them figure out they needed 87 PIR insulation boards at 100mm thickness with a lambda value of 0.022 W/m.K.
“We needed the insulation boards to be as thin as possible while still achieving the required thermal performance,” they said. “We did explore other types of insulation options other than PIR for between the rafters, where we had a 400mm space, but ultimately, realised Celotex GA4100 PIR insulation boards were the best option for us.”
Due to the weight of the board, the couple found they didn’t impose additional loads on the existing structure so did not require any structural considerations.
And, where the insulation didn’t fill the total rafter depth, low-emissivity foil facings gained additional thermal benefit from the air spaces they faced into.
When it came to installing the boards, the couple were pleased with how precisely they were able to cut them with a regular saw: “I was surprised at how little dust was produced when cutting them,” Eve said. “I found that when installing the stone wool insulation type products, we experienced a lot more dust in comparison.”
What technical support did Ty and Eve get from Celotex to help simplify the installation process?
Clear installation guidance is essential for keeping projects on track. So when the couple had an issue with the rafters, they turned to the Celotex Technical Services team to provide them with some technical and practical support.
“The information we received from Building Control wasn’t super clear,” they explained, “so we contacted the Technical Services team at Celotex who were really helpful and managed to resolve the issue. They were so knowledgeable when it came to getting our questions answered.”
The results: A space that will work for the long-term
Eve and Ty’s experience highlights not just the value of careful planning, but also the importance of researching and choosing the right insulation. Celotex GA4100 PIR insulation boards provided the balance of thermal performance, space efficiency and the ease of installation they needed to bring their loft conversion to life. With the added guidance of the Celotex U-Value calculator, they could be confident their insulation met Building Regulations and would keep their new space comfortable for years to come.
Follow @thebramhallbuild on TikTok to see the full journey, from insulation installs to last-minute DIY dramas.
Planning a DIY project? Start with our U-value calculator to determine your insulation requirements, and contact our technical team for additional support.
