Types of garden rooms that can be constructed under permitted development without planning permission.

The term garden room encompasses a host of detached garden buildings from swimming pool enclosures, office or study room, gym room, hobbies room in fact anything you want really provided it can be classed as an ancillary use.

And there perhaps lies the rub. Many Planning Departments determine any large buildings compared the original dwelling or plot not to be of an ancillary use. Also, garden rooms containing too many facilities that could form the basis of an independent dwelling or contain sleeping space usually fall outside of what is considered to be an ancillary use.

However, some garden room suppliers have experienced alternative interpretations from some Local Councils that permit annexes under Class E of the GPDO. The definition these councils use for determining ancillary use is whether or not the proposed garden room has a high dependency upon the main dwelling. Therefore, it could be argued that a garden building containing bedrooms and washing facilities for example but does not have a kitchen still has a high dependency upon the original dwelling and is therefore of an ancillary use.

Regretfully, most Planning Departments are not that liberal with their thinking and usually jump on any avenue or excuse to class a detached Class E garden room building as not being ancillary.

The term ancillary is not just restricted to its use. Ancillary can also mean in size and scale of the new garden room so hence large garden buildings on plots containing small dwellings may not be considered ancillary.

For a diagram of the restrictions affecting detached garden rooms click here.