Class R Permitted Development for Farm Buildings: Why It Won't Give You Class H Rights
Redundant farm buildings are one of the most valuable untapped assets on many holdings, and Class R permitted development rights make it possible to switch one from agricultural to business or light industrial use without a full planning application. But that quick route comes with a limit that catches farmers out: it does not carry the same extension rights as a building that reached commercial use through full planning. Getting this distinction wrong can leave a farm business boxed into a footprint it can never grow, at exactly the point diversification income matters most.
What Class R Permitted Development Actually Allows
Class R sits within Part 3 of the General Permitted Development Order 2015 and lets farmers change the use of an agricultural building to a business, storage, or light industrial use without submitting a full planning application. The building must have been used solely for agriculture as part of an established agricultural unit, and the change of use is capped at 1,000 square metres of floorspace on any one unit.
Rather than a planning application, the process runs through prior approval. The local planning authority still has to assess matters such as transport and highways impacts, contamination risks, noise, and whether the site is in a location where the change of use should reasonably be prevented. It is faster and usually cheaper than full planning, which is exactly why it is the first route most farmers consider when a shed or barn stops earning its keep.
Why Class R Doesn't Come With Class H Extension Rights
Class H, also in Part 3 of the GPDO, allows further extension of a building already in industrial or warehouse use. It sounds like the natural next step after a Class R conversion, but it only applies to buildings that reached that use through a full planning permission, not through permitted development.
That means a former agricultural building switched to commercial use under Class R stays capped at the footprint it had on the day of conversion. Any request to extend it later has to go through a fresh planning application in its own right, assessed against normal planning policy rather than treated as a simple extension of an existing permitted use. Farmers who assume the two rights stack together often find this out only once they need the extra space.
What This Means for Your Farm Business
The practical question is not whether Class R is useful, it clearly is, but whether it is the right route for a building you expect to outgrow. A yard or workshop that will only ever need the space it has today is well suited to Class R: it is quick, avoids planning fees, and gets a redundant building earning again. A building destined to become the base for a growing operation is a different case entirely.
Several well-publicised farm diversification stories in recent years have turned on exactly this point: a business outgrows the shed it started in, only to discover the footprint is fixed and a full planning application is now required to go any further, competing with every other application on the council's desk rather than sailing through as a simple extension. Deciding upfront whether to take the slower full planning route, precisely because it preserves room to grow, can save a farm business years of delay and a second round of fees further down the line.
How Foxes Rural Can Help
We work with farmers across England to weigh up permitted development against full planning before a single application goes in, drawing on RICS and CAAV-qualified expertise and a clear understanding of how CLA and NFU guidance applies to real farm buildings, not just textbook cases. If you are weighing up Class R against full planning for a redundant building, or you have already hit the Class H ceiling, call us on 01206 481981 or get in touch through our Contact page and we will talk through the right route for your site.