S.I. No. 340 of 2026 · in force since 27 July

Find out if your back garden qualifies. In about a minute.

Ireland's planning rules changed in July. A detached, habitable home of 32–45 m² can now go in a rear garden with no planning permission — if you meet every condition. We check all of them and write the letter you have to send.

Check my garden Free. No sign-up. Nothing to install.
32–45 m²
the size band Class 3A covers — there is a floor as well as a ceiling
1,591
days until the exemption expires on 31 December 2030 — work must be finished, not just started
14
days' written notice to your local authority before you can break ground

What the exemption actually allows — and what it doesn't

Most write-ups only cover the first column. The second is where people get caught.

✓ Allowed

  • A detached, habitable dwelling of 32–45 m² in your rear garden
  • No planning application, no waiting for a decision
  • Occupied by your household, or as a home office or studio
  • You notify the council; you don't ask permission

✕ Not allowed

  • Short-term letting is prohibited outright — Condition 19 of the regulations
  • Selling or subdividing it away from the main house
  • Anything under 32 m² or over 45 m², counting existing sheds and garages
  • Independent water, power or drainage connections
  • Investment or rental properties — owner-occupied principal residence only

! The exemption covers planning only

Building Control Acts and the Building Regulations still apply in full — structure, fire safety and Part L energy performance. Getting the planning side right does not make the building compliant. Any supplier who tells you otherwise is selling you a problem.

What it costs

Nothing. There is no account, no trial, and nothing to buy on this site.

What you get, free

  • Every Class 3A condition tested against your own measurements
  • Both statutory notices explained, including the Commencement Notice most write-ups omit
  • A covering letter drafted to go with your council's own notification form
  • Emailed to you if you want it, or printed straight from the page

Why it's free

We design and supply energy-efficient garden dwellings and the heating and solar that goes in them. This checker exists because we would rather meet people at the point where they are working out whether they can build at all, than sell to someone who finds out too late that their plot does not qualify. If you never speak to us again, the checker still works.

Manufacturers and installers

If you sell garden rooms or modular homes in Ireland, your customers are asking you this question right now. You can put the checker on your own site, under your own branding, and keep the enquiry.

Two lines of HTML:

<div data-breakground="your-company"></div>
<script src="https://breakground.build/embed.js" async></script>