Windsor Garden Offices and Garden Rooms


  • Maintenance free design
  • 600mm soffits x 200mm facias all round
  • EPDM Rubber Roofing System
  • Fibre cement cladding in a range of colours
  • Double glazed windows and doors
  • Flexible designs with sturdy construction
  • Very well insulated for all year round use
  • ‘L’ and ‘U’ shaped buildings – not a problem
  • Breathable membrane
  • DPC underlay as standard
  • Finish plastered
  • Decorated with skirting, architrave & coving
  • Engineered Oak laminate floor with underlay

The Windsor range of Garden Offices and Garden Rooms are manufactured to the highest quality and built on site by our highly skilled installation team and there are a large range of sizes to choose from. The Windsor Garden Room can be used as a Garden Gym, Garden Room, Garden Office, Guest Accommodation or just somewhere to relax.

The Windsor Garden Room is manufactured using 3” x 2” framing, externally clad with 11mm OSB moisture resistant sheeting, wrapped in a breathable membrane and overlaid externally with 25mm cavity battens to allow ventilation and cabling for external electrics.  The final external finish is clad with a Cedral fibre cement cladding which comes in a range of colours and is maintenance free. Marley Cedral Colours

Internally there is a 25mm layer of Celotex which is taped to ensure the building is air tight, finished with plasterboard, plaster skimmed for final decoration and finished with skirting.  We also incorporate within the price decoration in either white or magnolia including the skirting and architrave.

When we install your building we will install a damp proof course between the base and the pressure treated floor bearers which are 3” x 2” on their side. We then build a 3” x 2” frame around the outside of the base and insert an additional layer of 3” x 2” pressure treated bearers at 600mm centres. In between the bearers we insert 25mm Celotex and tape them together to provide an airtight layer of insulation. Next we overlay 18mm moisture resistant OSB and finish with an engineered Oak floor with underlay to make the floor more comfortable to walk on and quieter.  Where the walls interlock onto the edge of the floor we fit another damp proof course to stop any moisture ingress coming in under the bottom rail of the wall.

As a standard and within the price we provide a set of 1200mm wide white uPVC double doors and two windows which are 1965mm high x 760mm wide. If you require windows and doors in a different colour we can provide those if requested. Also if you require additional windows and doors, patios doors or bi-folds, or even partitions we can build those into the design too.

Roof Construction

The roof construction is of the highest quality with 2 x 6” x 2” pressure treated joists every 600mm which are bolted together for extra strength and come into their own on the deeper buildings to ensure a ridged structure with no noticeable flex. On top of the joists we use 18mm moisture resistant OSB sheeting followed by the roof covering.   The roof covering is a rubber roof known as EPDM Rubber Roofing and has many advantages over traditional bitumen flat roofs:

  • Increased longevity – In excess of 40 years
  • Improved weather resistance.
  • Safe Installation
  • Wider rolls which provide minimal overlaps and seams
  • EPDM is very flexible on corners and edges providing greater water resistance and in the unlikely event of a rip or tear can be simply repaired
  • EPDM offers a more weather-resistant solution. With the ability to expand or contract according to the prevailing weather conditions, EPDM is highly resistant to extremes of temperature in the range -50°C - 150°C. Wind and standing rainwater does not compromise the surface and EPDM insulates heat effectively meaning internal rooms are cooler in summer and warmer in winter.

The EPDM Rubber Roof is then finished with steel trims around the soffits to protect the edges.  The Soffits provide a 600mm overhang to provide further protection from the elements and the facias are 200mm deep.

Internally within the roof section we install 25mm Celotex and again tape it to make it air tight.  This is then covered over with plaster board, plastered and decorated.


All our Windsor garden offices and garden rooms come with Ogee guttering in brown, black or white.


Each of the Windsor range of garden rooms come with a full electrics pack, which includes a consumer unit, internal spots, double sockets and porch lights with two switches

Standard Specification at a Glance

  • External Clad - 10mm x 190mm Cedral Weather Board maintenance free cladding in a range of beautiful colours – Marley Link
  • 6 Layer Fully Insulated Heavy Duty Floor - Damp proof course underlay, 3” x 2” pressure treated bearers, another layer of 3” x 2” pressure treated bearers at right angles, 25mm Celotex plus 18mm OSB moisture resistant sheeting, underlay and an engineered Oak floor.
  • 8 Layer Fully Insulated and Lined Wall Specification – Cedral Weather Board cladding, 25mm cavity battens, 11mm moisture resistant OSB sheeting, breathable membrane, 3” x 2” framing, 25mm Celotex, plaster board and a plaster finish. This gives an overall wall thickness of circa 165mm (6.5”). The Oak floor options available are in the gallery below or can be viewed via this link Oak Floor Options
  • Mono Pitched Roof – Mono Roof sloping from front to back. Cedral Weather Board barge boards hide the fall of the roof and the guttering when viewed from the front.
  • Ground Work – There are a range of options, Concrete base, timber base or existing hard standing.  For more information please click here or contact us for advice.
  • Double Doors – The Contemporary Garden Room doors are 1200mm wide white uPVC double glazed doors. We can also supply a range of colours if required.
  • Windows – The standard two double glazed are white uPVC windows supplied with each building are 1965mm high x 760mm wide and also come in a range of colours, please ask for range of colours and associated costs.  Other sizes are available on request and you can purchase additional doors and windows depending on the size of the building.
  • Insurance recognised locking system to doors and windows – The doors have a multi-lock system and the windows have locking handles
  • Colour Options – The doors and windows come in a range of colours and are available on request.
  • Skirting, Architrave & Coving – MDF primed skirting, architrave and coving are Included. 
  • FSC Sustainable timber – All timber is from Scandinavian certified and sustainable forests.
  • Breathable Barrier – This built in barrier is an essential element of the structure to keep the damp out of the building and allow the timbers to breathe.
  • Lighting – The building will be supplied with chrome GU10 down lights, the number will depend on the size of the building.
  • Sockets and Consumer Unit – The sockets and switches come with chrome face plates.  The Consumer unit comes with three switches, 6amp for the lights and 16amp for the sockets and a spare.  It also has an RCD built into it.  Again the number of sockets depends on the size of the building and more can be purchased if required.
  • Roof Overhangs – The Mono roof comes with a 600mm standard overhang all-round the building and the soffits are 200mm deep. The soffits and facias are normally reduced in size on smaller buildings.
  • Guttering – All our garden offices and garden rooms come with guttering Ogee guttering in brown, black or white.

Available Optional Extras

  • Rounded corners
  • 4 or 3.0m wide patios doors
  • Bi-Fold doors
  • Aluminium door and windows
  • MDF moisture resistant tongue and groove (T & G) interior walls
  • Part MDF moisture resistant (T & G) walls and part plaster
  • Partitions and internal doors
  • Additional doors and windows
  • Colour up-grade on uPVC doors and windows
  • Up-grade to Rationel doors and windows
  • Fireproof internal plaster board to satisfy Building Regulations
  • Internal Vapour Barriers to satisfy Building Regulations
  • Decking
  • Gazebos
  • Bathrooms & wet rooms
  • Kitchen & utility rooms
  • Partitions and bedrooms

 Finance and Funding Options

  • Garden Retreat can provide either Hire Purchase or Finance lease options and there is also a large amount of other funding resources available. Please click here for more information on Finance and Funding Options

Planning Information

If you require planning information we are happy to advise and support, please click here for further information.

All prices include installation, VAT, the only additional cost would be delivery which is listed in the table below.

For further information please either complete the contact form below or call one of our team.

Prices & Sizes

















































































  *Other sizes are available and all prices include delivery, installation and VAT*


Contact Us

Contact us for more information.