Garden room SIPs kits

If you dream of building your own inspiring workspace, home yoga studio, guest annexe or a special place for the kids to play, explore our range of sustainable SIPs garden kits which come installed by our expert construction crew. We’ve come up with the most eco-conscious SIPs design to give you the best performance and value for money from your structure. Below you will find all of the information you’ll need to get started with your own garden build project.

Why choose a SIPs Eco-room? 
  • A garden building constructed using SIPs can be erected up to 60% faster than with traditional construction methods
  • SIP structures are more attractive to future buyers and often achieve a much higher sale price
  • Unlike traditional construction methods which rely on good weather, SIPs are erected regardless of the weather conditions
  • Our EPS insulation is 98% air and just 2% plastic and provides a U-value of 0.23 meaning lower heating costs
  • The lightweight SIP shell reduces the need for heavy machinery and concrete production on-site (great ways to reduce your project’s carbon footprint)
  • The timber used to create the outer skins and structural framework of our SIP panels come from FSC accredited sources

Design options

Eco-room SmallMediumLarge
Width2.4 m3.7m4.9m
Time to install1.5 days1.5 days2 days
DeliveryFree (60 miles of BH23 8EA)Free (60 miles of BH23 8EA)Free (60 miles of BH23 8EA)
Panel thickness145mm145mm145mm
EPS insulation core123mm123mm123mm
Internal finish11mm OSB11mm OSB11mm OSB
External finish 11mm OSB11mm OSB11mm OSB
Price£4,375 (inc. VAT)£4,850 (inc. VAT)£5,495 (inc. VAT)

Small Eco-room

£4,375 (inc. VAT) 
Inc. delivery & installation

Medium Eco-room

£4,850 (inc. VAT) 
Inc. delivery & installation


Large Eco-room

£5,495 (inc. VAT) 
Inc. delivery & installation

All designs

Order your SIPs Eco-room now

What’s included?

We manufacture and install a complete shell for your garden structure, containing the requisite number of SIPs to construct the walls, floor and roof, in the specific sizes of the model laid out in the tables for either our small, medium or large Eco-room. You can then choose to finish your garden room however you wish. We aim to make life as simple as possible and supply all the elements needed for construction:

  • A detailed plan and elevations drawing pack to share with your builder
  • Manufacture of SIP panels for walls and roof
  • Window and door apertures pre-cut and structurally framed with timber
  • Haulage and delivery to site
  • Installation of SIP panels from foundations up inc. the items below
  • Treated timber floor frame with 70mm, foil-backed insulation*
  • Engineered Glulam beam lintel above the doorway
  • Sole and wall plates, timber fixing splines and joining timbers
  • Caberdeck (22mm) moisture resistant T&G flooring
  • Specialist SIPs screw fixings, adhesives and sealants
  • Walls and roof wrapped with breather membrane to achieve weatherproofing

* ideal for sitting on ground screws or pads, we can also accommodate building up from a concrete slab


Our professional team of site technicians can ensure the accurate and efficient installation of the SIP panels for your garden build. To keep our carbon footprint and the cost to our clients low, we offer free installation within a 60-mile radius of our New Forest workshop (BH23 8EA). We are able to offer installation outside of our preferred catchment area, however, additional costs will be added to our prices highlighted above in order to cover the added expense for our construction crew’s travel and accommodation. Our SIPs are incredibly quick to erect, see the design options table above for an overview of site times required for our range.


A great building needs strong foundations. That’s why you’ll need to consider the type of base that your garden build will be constructed on. Our package does not include foundations and is on the basis that all groundworks have been installed by others prior to our arrival on site. We recommend one of three types of foundation to be in place ahead of the SIPs structure installation, simply let us know which type you are using in the Eco-room order form and then we will send you a detailed drawing of the floor section for you to share with the groundworks company.

Ground screws are galvanised pins that screw into the ground with precision to create a strong and level platform for your garden room, office or leisure building. Environmentally, ground screws offer a huge reduction of emitted carbon compared to a traditional concrete base. We recommend the Great British Ground Screw Company as our preferred supplier.

Pads offer another innovative solution, especially where the rocky ground makes digging really difficult. Environmentally, the pads can also be a great way to reduce your carbon impact. That’s why we’ve teamed up with a preferred supplier that produces its pads from 100% recycled plastic – we recommend Jackpad.

Concrete slabs can also be used as the base for your SIPs structure. Through our established network of main contractors, we can recommend local professionals to assist with this process if necessary.

Completing your build

You may prefer to have one main contractor overseeing all the works on your garden build project, so we’ve teamed up with a network of local main contractors who specialise in the garden building installation that we can recommend. Essentially, they are responsible for all the work before and after the installation of the SIP shell structure. Likewise, if you’re a DIY enthusiast or have your own carpenter or builder, we’ll happily put up the SIPs structure once the site is ready and then leave it to be finished to your own style.

Windows and doors

All our window and door apertures are pre-cut and structurally framed with timber. This allows you/your builder to easily install your own choice of windows and doors with ease. All our kits come with a left side window as standard (as per our drawings), however, if you would like to swap this for a right-hand side one instead, have windows on both sides, or no windows at all then you can select this on the order form without any additional charge. We suggest that you use our guide below which outlines the specific measurements you’ll need when ordering from your chosen supplier. Remembering to allow a tolerance gap of at least 5-10mm for the top and sides when ordering your units, as this allows for sufficient room when fitting your windows and doors correctly. Also, ensure that the measurements given by your manufacturer include the height of the sills. If you choose to use non-opening windows or no windows we would advise that you order your doors with trickle-vents in order to allow some ventilation of the space when not in us. See our guide below for more details.

 Small MediumLarge
Window (side)2,025mm x 620mm 2,025mm x 620mm 2,025mm x 620mm
Door1,998mm x 1,638mm1,998mm x 2,036mm1,998mm x 3,258mm
EPDM (ethylene propylene diene monomer) membranes are particularly suitable for flat roof applications, it is a highly reliable and durable material which can easily be applied without any special tools or specialist knowledge. The International Kyoto Ecology Agreement recommend EPDM rubber as the best value and sustainable roofing option. Whilst, international environmental agency, Greenpeace, put EPDM at the top of their rankings of low-impact membranes due to its extended lifespan and re-usability. EPDM membrane roofing is also ideal for providing a waterproof rubber roof coating required for a green roof with sedum plants forming the top layer.
We recommend Rubber4Roofs as your EPDM roofing supplier. Check out their handy kit calculator which helps you/your builder order the full kit of parts required for your garden build roof.

Want something bespoke?

Every garden is different and we appreciate that you may want something bespoke to meet your specific project needs. Our in-house design experts can produce SIPs drawings to match your specific project sizes. For a quick and simple estimate, just complete our quote enquiry form.

Planning permission

Some garden projects will need to apply to the local planning authority for planning permission prior to commencing any works. However, there are several scenarios where planning permission may not be required*. As a guide, outbuildings are generally considered to be permitted development, without the need for planning permission, subject to certain conditions. For example:

    • Outbuildings must be single-storey with a maximum eaves height of 2.5 metres and maximum overall height of 4 metres with a dual pitched roof
    • For outbuildings within 2 metres of the property boundary, maximum height is 2.5 metres
    • Verandas, balconies or raised platforms are not permitted
    • No more than half the area of land around the original house should be covered by additions or other buildings
    • If your property is a listed building, on designated land or within a national park, further restrictions apply

For a full list of planning requirements, go to Planning Portal.

Whether you require planning permission or not, we’d love to help you understand the costs for the SIPs structure of your project.

* whilst we can signpost our clients to relevant literature, we do not offer a planning application or consultancy service. Therefore, we highly recommend that you check with your local planning authority ahead of embarking on your garden room project.

Order your SIPs Eco-room now