100mm
SIP Panels
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As standard, all our SIP extensions and garden room builds are finished with high-quality, naturally insulating structurally insulated panels (SIPs).
Our SIP panels are used throughout your walls, flooring and roof, creating an airtight and insulated structure, which can be used all year-round. They’re far mote energy-efficient than traditional builds, helping your extension or garden room stay warm in winter and cool in summer.
With SIPs, you’ll get a custom garden building that’s stronger, warmer and more efficient from day one.
100m SIPs as Standard
All our SIP extensions and garden rooms are built using 100mm SIP panels as standard. This thickness provides an excellent balance of strength and insulation.
This means lower heating costs and better temperature control in a garden structure that is looks like a true extension of your home, not just an outdoor shed or workspace.
Our 100mm SIPs deliver reliable performance from day one, making them the ideal foundation for a high-quality, energy-efficient build.
Upgrade to 150mm SIP Panels
For even higher performance, we offer an upgrade to 150mm SIP panels. These thicker structurally insulated panels provide noticeably improved insulation and soundproofing benefits.
These panels are suited to more functional builds, which are going to be used heavily in the winter (like with garden annexes and offices). Or in instances where you want extra sound reduction like with music rooms or man caves.
Upgrading to 150mm SIPs means your garden room or extension will be able to hold heat for longer, stay cooler on hot days and feel ever more like part of your home main home – all while keeping energy cots down.
SIP Panelling FAQs
SIP panels (Structurally Insulated Panels) are strong, insulated building panels used to create the walls, floor and roof of our garden rooms and extensions.
They offer excellent thermal performance, quick installation and a clean, solid finish. This makes them perfect for comfortable, long-lasting spaces.
100mm SIPs come as standard and offer great thermal performance for most garden room and extension uses.
150mm SIPs provide even better insulation and sound reduction, making them ideal if you want the highest comfort levels or plan to use the space heavily through the colder months.
Using SIP panels, we can build and furnish your garden rooms and SIP extensions in just under 2 weeks.
Most garden rooms can be installed within a few days once the base is ready. Using SIPs for an extension is also faster than traditional constructions.
You can, but not directly onto a SIP roof.
If you’d like skylights or a roof lantern on your build, we simply install an insulated timber roof (or upgrade to an EPDM rubber roof), allowing us to fit your chosen glazing safely and securely.
Absolutely, you can choose layouts, cladding styles, finishes, glazing options and internal features to create a space that suits your home and how you plan to use it.
Any garden building will require a foundation. We can build on a concrete base, ground screws or another suitable foundation depending on your site.
We can guide you on the best option to ensure a stable, lasting structure.
Our Clients & Feedback
EXCELLENT Based on 35 reviews Posted on Johnnie FiveTrustindex verifies that the original source of the review is Google. Lovely team to liaise with from beginning to end. Swift work and lovely finish.Posted on Andy GambleTrustindex verifies that the original source of the review is Google. From the initial quote right through to completion of our single storey SIP extension, we were in safe hands. We were surprised by how fast everything was! Dan will go above and beyond to make sure that the customer is happy - he will suggest ideas, and alternatives, but will ultimately do whatever you ask for. He will answer all your questions. The team that did the build were a friendly crew; the office team were always patient and helpful when I asked for updates. We are very happy with our extension and I wouldn't hesitate to recommend this company.Posted on Dave HallTrustindex verifies that the original source of the review is Google. We were impressed with Greenleaf. They were really helpful from the initial enquiry through to subsequent queries when we were finalising the design. The installers were a professional bunch as well and were good to work with. We’re very happy with the end result.Posted on Emma CarterTrustindex verifies that the original source of the review is Google. A superb experience from start to finish. Our extension was built exactly to our requirements. We had lots of questions and these were all answered quickly and professionally. Despite the weather not always being on our side, the build was completed within the week’s quoted time frame and completed to the highest of standards. All of the staff were professional and efficient throughout. Lots of people have commented on how good the extension looks! We would whole-heartedly recommend this company.Posted on freemomTrustindex verifies that the original source of the review is Google. Dan and his building team were fantastic. Could't believe they built my 5x3m garden house just in a few days. They had long drive to my place but still popped up in the early morning. They were professional and with good workmanship. The communication within the company was so good that they didn't make any mistake throughout the whole process. They could build exactly what I wanted. We were so happy for making the right choice. Can't recommend the team enough!Posted on J MMTrustindex verifies that the original source of the review is Google. Our build has been a massive investment for me to contemplate and I wanted to be 100% sure that they would provide the best for us - & they did ... I'm surprised they didn't turn down the job as I had a 1000 questions, before even starting ... But I honestly can not recommend the whole team enough! They have all been fantastic, they are friendly & approachable, give honest opinions but ultimately make sure that you are happy with the build, from start to finish, they have gone above and beyond. It is clear that they all take pride in what they do. I would not hesitate to recommend them. Thank you Dan and your team.Posted on Robert ChesnerTrustindex verifies that the original source of the review is Google. Brilliant quality garden room. Looks great! Dan and his team went above and beyond during the project. Thank youPosted on Stacey MorrisTrustindex verifies that the original source of the review is Google. After another company coming and building me a summer house and trying to rip me off. green leaf garden buildings 2 days later came and built one for me and WOW I love it! the guys have done a brilliant job! very quick service, reliable l, fits to preference would recommend to anyone.Posted on BATrustindex verifies that the original source of the review is Google. I cannot recommend Green Leaf Garden Buildings highly enough!!! From Shane visiting us to discuss ideas to Ashley in the office promptly answering all of our (many many many) questions to Dan, Shaun and all the guys installing the Garden Building - every aspect was exceptional and highly professional. I am blown away by how I was treated as a customer. Everything was clearly explained to us including the internal dimensions (important as we are a tall family!!), the electrics and the finish to ensure that we were completely happy. The standard of workmanship is flawless and excellent and they were meticulous, tidy, and so very friendly. They left my garden immaculate with no signs of works!! I had a large Garden Building (12m x 2.5m) and they built it in a week!! On the first day of the build it snowed so I was expecting a call from them to cancel but they turned up on time and worked through the bad weather every day. The work ethic of everyone who worked on our building is highly commendable. I had to delay the build by a few days but they pulled out all the stops to complete it within the original timescale and without cutting corners!! Throughout the process, I felt that making the customer happy meant more to these guys than anything else. They went over and beyond and because of the standard of workmanship, I feel that the investment in a Garden Building is worth every penny. We obtained many quotes and were nervous when deciding who to go with but we definitely 100% made the right decision going with Green Leaf. Thank you to the whole team!!!! If you are looking for Garden Room - DEFINITELY go with Green Leaf! You won't be disappointed!Posted on Paul HigginsTrustindex verifies that the original source of the review is Google. This was a very big investment for me. It’s fair to say I was hesitant and nervous but the team engaged positively, answering all of my numerous queries and being very transparent in terms of specification. The build went very smoothly and there was clear flexibility when it came to queries while it progressed and these were answered and addressed promptly. Any snags were resolved quickly. Whilst not a major issue in the slightest I did note that the specification was for an armoured network cable to be installed but upon inspection, a standard cat5 cable had been used, routed in the main through some plastic trunking. However, I had a constructive and open discussion about this with the team. I decided not to have the cable replaced. Whilst the provisioned cable was at a different price point, through our conversation I elected not to progress on an invoice revision as my overall experience had been a positive one. However, that the cable provided was not as expected is the only reason I rate at 4 stars rather than 5.Showing our latest reviews
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