Renting out a Class 3A garden home

Can you rent it out?

The Class 3A exemption was designed to add homes, so letting is allowed. But the garden home stays tied to the main house. It can only be lived in alongside the main house, it can't be sold or split off as a separate property, and the main house must be the owner's home when the work starts.

Rent a room relief

Citizens Information confirms that a detached garden home of 32 to 45 m² that meets the exemption criteria can qualify for rent a room relief from 27 July 2026.

The main conditions:

• The main house must be your home for most of the year.
• Stays must be long-term, meaning more than 28 days in a row.
• The limit includes everything the occupant pays, such as money for utilities, food or laundry.
• Not your own child. Rent from your child, or your spouse's or civil partner's child, doesn't qualify.
• Go over the limit and you lose the relief entirely. All the rent, less allowable expenses, is then taxed.

Licence, not tenancy

Reports on the new rules say lettings are expected to work as licences, modelled on renting a room in your own home, rather than tenancies registered with the RTB. A licensee has fewer protections than a tenant, so be clear in writing about the terms, notice and what's included.

What isn't allowed

• Short-term lets, including Airbnb and holiday lets.
• Selling the garden home separately from the main house.
• Separate utility connections. Services must come from the main house.
• Fencing it off or adding a new entrance onto the road.

Practical points

• Utilities: because services run from the main house, agree how electricity and heating are paid, for example a flat monthly amount.
• Insurance: tell your home insurer someone is living there and paying rent.
• Privacy: the garden home needs its own access within your grounds, and you'll share the garden. Agree how that works.