The RD SIPs Annex Kit — A Proper Habitable Annex. Built in Days. Certified for Building Regs.
A 26m² habitable SIPs annex designed to give you a genuine, high-performance living space — not just another garden room.
The walls meet Building Regulations, the roof outperforms most new-build specifications, and everything you need to get the structure to site comes together in one complete order.
A Proper Habitable Space
This isn't simply a timber garden room or basic outbuilding. The RD SIPs Annex Kit is designed as a proper habitable building, suitable for creating additional accommodation, a home office, guest accommodation, studio, family space or other year-round living space.
The SIPs construction provides excellent thermal performance while dramatically reducing the amount of time required to get the structural shell built.
What's Included
Everything is supplied as part of one coordinated SIPs package, helping to simplify ordering and construction.
- 147mm PUR-bonded SIP walls
- 172mm SIP roof panels
- Rubber roof covering
- Roof battens
- Breather membrane
- Structural adhesive / glue
- Expanding foam
- Screws and structural fixings
- Required timber components
- Structural calculations
- Technical drawings and plans
- Declaration of Performance (DOP)
- Technical support
Designed for Building Regulations
The annex has been designed around the requirements expected of a modern habitable building, with the structural and thermal performance of the SIPs system properly considered from the outset.
Certification & Quality
CATG
STA Gold
ISO 9001
STA Assure Silver
Made in Britain
SIP Mark Systems
High Thermal Performance
The SIPs specification provides excellent insulation performance, helping to create a comfortable building throughout the year and reducing heat loss compared with many conventional construction methods.
Why This Annex Kit Is Selling Fast
The major structural components and supporting materials are coordinated into one package, making ordering considerably simpler.
Structural calculations are supplied as part of the package, helping your project move forward with the correct structural information.
SIPs panels are manufactured to precise dimensions and can be assembled rapidly on site, significantly reducing structural construction time.
High levels of insulation and airtight construction make SIPs particularly well suited to comfortable year-round accommodation.
A properly designed and documented SIPs structure can make it easier to work with building control, designers and other construction professionals.
Factory-manufactured panels arrive ready to assemble, helping reduce cutting, waste and mess on site.
The high-performance insulation helps reduce heat loss and contributes towards lower energy requirements.
Faster structural assembly means less time spent on site compared with many traditional construction methods.
Components are manufactured in controlled factory conditions, giving you consistent panel quality and accurate dimensions.
RD SIPs can supply the annex kit to projects throughout the UK.
You're dealing directly with a UK family business specialising in Structural Insulated Panel Systems.
Delivery Day
Your SIPs panels and associated materials arrive ready for your project, allowing your construction team to move quickly into the assembly stage.
Because the panels are precision manufactured, the structure can progress rapidly once the foundations and site preparation are ready.
Designed Around Your Project
Every building project is different. The annex kit can be discussed around your intended layout, site conditions, openings and construction requirements.
Our technical team can provide support throughout the process, helping you understand what is required before your SIPs arrive on site.
Lead Times & Delivery
Typical lead times are approximately 4–8 weeks, depending on project requirements, production schedules and delivery arrangements.
UK-wide delivery available.
Winter Sale — Enquire Now
If you're planning a habitable annex, guest accommodation, home office or additional living space, this complete RD SIPs Annex Kit gives you a high-performance structural shell without the complexity of sourcing every component separately.
Speak to RD SIPs today and find out how we can supply your complete annex kit.
Enquire About The Annex Kit