Are the sizes given the internal or external measurements?

The measurements given are the ‘middle measurement’ which are the dimensions of the structure without the external or internal finishes. Below is a table showing you the exact size of some popular garden room sizes (excludes any canopy on roof & decking areas).

We can build to any size you require but due to the way the sips panels are manufactured, it’s more cost effective to stick to these dimensions as there is less waste during the manufacturing process.