Garden Rooms Technical Data


A well-insulated building will help keep it warm in winter and cool in summer. The degree to which elements of your garden room limit the heat transfer is measured by its U value. The lower the U value the more efficient the building is.

Using a 100mm thick SIP panel for the walls and 150mm for the roof and 75mm PIR in the floor we can achieve U-values of between 0.2 and 0.3 in these elements. If higher insulation rates are required a thicker SIP panel or PIR board can be used, however in the case of the floor and roof insulation the floor to ceiling height could be reduced. Limiting the amount of window area is an alternative way of improving insulation levels as the window U-values are higher and less thermally efficient.

Limiting air leakage through the structure is an important way of reducing heat loss. Our construction techniques and close control of fabrication will significantly limit any air leakage through the building fabric.


The Garden Room will effectively be a sealed box, to provide fresh air for the comfort of the occupants and stop the room ‘sweating’ either trickle vents to the windows or a wall vent will be provided.

Saunas need additional ventilation with an inlet and outlet to ‘dry’ the room following the sauna experience. We provide an inlet incorporated into the floor drain and a shuttered outlet at a high level.


To provide the firm foundation needed to ensure no future movement our rooms come with either concrete pad foundations or galvanised steel ground anchors, depending on the ground conditions.


We use an insulated timber base that is suspended above the ground providing the important air passage below, keeping the timbers dry and protected from rot.

Walls and Roof

By using the SIP panels in these two elements we achieve high levels of insulation as well as a strong frame.

Exeter sauna steam room