SIP Garden Room Kits Supplied Pre-Cut and Ready to Assemble
Pre-cut SIP garden room shell kits for self-builders and trades. Supplied with SIP floor, wall and roof panels, structural splines, timber components and fixings, ready to build on a prepared level base.
DIY SIP Garden Room Kits for a Faster, Warmer Shell Build
SIP Garden Room Kits is the dedicated supply-only kit site for customers who want a strong, insulated garden room shell without building the full structure from timber frame on site.
Each kit is designed around structural insulated panels, giving you the main floor, wall and roof shell ready for your chosen doors, EPDM roof covering, breather membrane, battens and external cladding.
We currently prioritise delivery across the North West, with wider UK delivery considered by quotation depending on kit size and location.
Popular SIP Garden Room Kit Sizes
Choose one of our standard SIP shell kit sizes below, or request a custom quote if you need a different footprint, opening layout or plain cube kit.
2.44m x 2.44m SIP Kit
A compact SIP shell kit suited to a small garden office, hobby room, treatment room or garden studio.
3.66m x 2.44m SIP Kit
Our most popular shell size, giving a practical garden office or studio footprint while keeping the build straightforward.
4.88m x 2.44m SIP Kit
A wider SIP shell kit suited to a larger garden office, gym space, studio or multi-use garden room.
View All SIP Garden Room Kit Sizes
We supply a wider range of standard SIP shell kit sizes than the three featured above. The prices below show our limited 10% summer offer until 31/07/26. All prices are for the supply-only SIP shell kit and exclude VAT, delivery, doors, cladding, EPDM roof kit, base, electrics and internal finishes.
2.44m x 2.44m
Usually £1,995 + VAT Now £1,795 + VAT Save £200 until 31/07/26
Compact starter kit for smaller gardens, offices and hobby rooms.
View This Kit3.05m x 2.44m
Usually £2,295 + VAT Now £2,065 + VAT Save £230 until 31/07/26
Practical mid-size kit with more usable width.
View This Kit3.66m x 2.44m
Usually £2,495 + VAT Now £2,245 + VAT Save £250 until 31/07/26
Popular garden office and studio size.
View This Kit4.27m x 2.44m
Usually £2,695 + VAT Now £2,425 + VAT Save £270 until 31/07/26
Wider shell kit while keeping a compact depth.
View This Kit4.88m x 2.44m
Usually £2,995 + VAT Now £2,695 + VAT Save £300 until 31/07/26
Larger wide-format kit for offices, gyms and studios.
View This Kit3.66m x 3.05m
Usually £3,295 + VAT Now £2,965 + VAT Save £330 until 31/07/26
More depth for a flexible everyday garden room.
View This Kit4.88m x 3.05m
Usually £3,795 + VAT Now £3,415 + VAT Save £380 until 31/07/26
Large kit with extra width and depth.
View This Kit6.10m x 3.05m
Usually £4,295 + VAT Now £3,865 + VAT Save £430 until 31/07/26
Largest standard shell kit in the current range.
View This KitWhat’s Included in a SIP Shell Kit?
Our kits are supplied as the main structural SIP package for the garden room. This keeps the kit clear, flexible and cost-effective, while allowing you to choose your own doors, cladding and final finish.
Included
- SIP floor panels
- SIP wall panels
- SIP roof panels
- Structural splines
- Timber components
- Fixings pack
- Standard panel layout drawing
- Basic assembly guidance
Quoted Separately
- Delivery
- Doors and windows
- External cladding
- EPDM rubber roof kit
- Breather membrane and battens
- Custom openings and extra trimming
- Steel support where required for larger openings
- Base, foundations, electrics and internal finishes
Real customer build — from SIP shell to finished room
These are real customer build photos, not stock images or showroom renders. The finished room shown at the top of this page is the same build shown step by step below.
Why Choose a SIP Garden Room Kit?
Warmer Shell
SIP panels form an insulated structure from the start, helping create a more usable year-round garden room shell.
Faster Build
Pre-cut panels, splines and fixings help reduce time spent setting out and building a full timber frame on site.
Clear Inclusions
We separate the shell kit from extras, so you know exactly what is included and what needs quoting separately.
Flexible Finish
Add your own doors, cladding, roof covering and internal finish to suit your budget and final use.
How the SIP Kit Build Works
The kit gives you the main insulated structure. Once the SIP shell is built, you can complete the roof covering, weather protection and external finish.
Prepare the Base
Your base needs to be flat, level and structurally suitable before the SIP kit is delivered and assembled.
Assemble the SIP Shell
The SIP floor, wall and roof panels are joined with the supplied splines, timber components and fixings.
Finish Externally
Add EPDM roof covering, membrane, battens, cladding, doors, windows and trims to complete the garden room externally.
Standard Kits or Custom SIP Shells
Standard SIP Kit Sizes
Standard kit sizes are usually the most cost-effective option because they follow our normal panel layout and manufacturing process.
Custom Sizes and Openings
We can quote for custom footprints, large door openings, side doors, window apertures or plain cube kits with no factory-cut openings.
Customer Feedback
Feedback from previous SIP garden room kit customers.
“The kit arrived well packed and the shell went up quickly. Clear communication throughout and exactly what we needed for the build.”
Daniel, Penketh SIP garden room kit customer“Helpful advice before ordering and a clear breakdown of what was included. The kit made the build much more straightforward.”
Paul C, Woolton SIP garden room kit customerFrequently Asked Questions
Is this a fully finished garden room?
No. This is a supply-only SIP shell kit. It includes the SIP floor, wall and roof panels, splines, timber components and fixings pack. Doors, windows, cladding, EPDM roof kit, delivery, base, electrics and internal finishes are quoted separately unless specifically agreed.
Are doors and windows included?
Doors and windows are not included as standard. You can supply your own, or we can quote separately depending on the size and specification required.
Can you manufacture custom openings?
Yes. We can allow for custom openings such as patio doors, bi-folds, windows or side access doors. Larger openings may require additional trimming, timber and steel support, which can affect the final price.
Can I order a plain cube and cut my own openings?
Yes. A plain SIP cube with no factory-cut apertures is usually the most cost-effective option. If you cut your own openings on site, they must be trimmed and supported correctly, especially for larger door openings.
Is delivery included?
Delivery is quoted separately. We currently prioritise North West delivery, with wider UK delivery considered by quotation depending on location and kit size.
What base do I need?
You need a flat, level and structurally suitable base before the SIP kit is installed. The base must be ready before delivery and assembly.
Do I need planning permission?
Many garden rooms can fall within permitted development, but this depends on size, height, position, use and your property. You should check the current Planning Portal guidance or speak to your local authority before ordering.
Manufactured by Sips & Splines
SIP Garden Room Kits is supplied by Sips & Splines, a trading name of HFI Services Ltd. Based in Liverpool, we manufacture SIP garden room shell kits for self-builders and trades across the North West and beyond by quotation.
Our focus is on strong, insulated shell kits with clear pricing, practical panel layouts and straightforward advice before you order.
Looking for a Fully Installed Garden Room?
This site is for supply-only SIP garden room shell kits. If you are looking for a premium fully installed garden room instead, you can visit our sister site below.
Visit Our Fully Installed Garden Room Site →Need a Price for Your SIP Garden Room Kit?
Send us your rough dimensions, delivery postcode and any door or window positions. We’ll confirm the closest kit size, include the 10% summer offer where applicable, and show clearly what is included and what extras need to be allowed for.
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