The 45m² garden home planning exemption in Ireland, explained

What the exemption actually allows

Since 27 July 2026, Irish homeowners have been able to build a permanent, detached, habitable dwelling in the rear garden of their main residence without going through a full planning application — provided it meets a specific set of conditions.

This is a genuine change. Previously, a habitable unit in your back garden almost always required planning permission, with the delay, cost and uncertainty that involves. The exemption removes that step for units that fit within defined limits.

The size limits, and why 32m² is the floor

The exemption applies to units between 32m² and 45m². The upper limit is the one everyone focuses on, but the lower limit matters too — a smaller unit doesn't automatically qualify under this exemption simply by being smaller. If you're building something under 32m², you're likely looking at a different set of rules entirely, such as those covering garden rooms and home offices, which are not habitable dwellings.

To put 45m² in context: that's roughly the size of a modest one-bedroom apartment. Enough for a bedroom, bathroom, and a combined living and kitchen space. It's a real dwelling, not a shed with a bed in it.

Height limits — the detail that catches people out

There are two different height limits depending on your roof:

• 4 metres if you have a pitched or tiled roof
• 3 metres for any other roof type — including flat roofs

This matters more than it first appears, because many modern modular garden homes and pods are designed with flat or very shallow roofs for a contemporary look. That design choice drops your permitted height by a full metre. If you're comparing suppliers, ask what the finished height will be including the base it sits on — a unit that's 2.8m tall sitting on a 300mm base is 3.1m overall, and that's over the limit.

The 14-day notification — don't skip this

Exempt does not mean invisible. You must notify your local authority at least 14 days before work starts. This is not a planning application and it isn't something they approve or refuse in the normal sense — it's a notification. But it is a requirement of the exemption, and skipping it undermines your position if a question arises later.

Practically: build the 14 days into your timeline. If your supplier has a delivery slot booked, work backwards from that date. Some suppliers will handle the notification paperwork for you — worth asking, because it's one less thing to get wrong.

What still applies — this is the big one

This is the single most misunderstood part of the new rules. "No planning permission required" gets read as "no rules apply," and that's wrong. Your garden home still needs to meet requirements covering structural safety, fire safety, insulation and energy performance, ventilation, and drainage.

In practice this means the cheapest possible unit is rarely the cheapest overall. A structure that isn't built to habitable standard may satisfy nobody — not Building Control, not your insurer, and not a future buyer of your house.

The 2030 deadline

The exemption is time-limited: it currently applies to homes built between 27 July 2026 and 31 December 2030. That's a real window, not an open-ended right. Whether it gets extended is unknown — plan on the basis of the rules as they stand, not on the assumption they'll continue.

The part nobody tells you about: getting it into the garden

Here's where most people get caught out, and it has nothing to do with planning.

Buying the unit is one job. Getting it into your back garden is a completely separate one — and often a harder one. A 45m² modular home is a large object. Your side passage is probably not wide enough for it.

There are three distinct services involved, and — this is the bit that catches people — they are usually three separate hires from three different companies:

• Delivery and transport — a haulier brings the unit to your property, usually dropping it at the gate or driveway. Often arranged through the seller. Getting it any further is not normally included.
• Siting and placement — manoeuvring the unit into its final position on the base. Requires side access wide enough to physically get the unit through. The haulier may do this if access allows.
• Crane hire and lifting — if there's no side access, you hire a crane firm separately to lift the unit over the house, wall or fence. This describes most urban and suburban gardens in Ireland.

Crane firms lift. They don't normally deliver. That's the single most common misunderstanding here — people assume booking a crane means the unit turns up too. It doesn't. You arrange transport, and you book the crane, and the two need to be coordinated to arrive on the same day.

Crane hire is not a trivial cost, and it's not something to discover on delivery day. Before you commit to buying, get someone to assess your access — a crane firm will usually do a site access assessment, and some suppliers include this.

And before any of that: the base

Your garden home needs something to sit on. The main options are a concrete slab, or ground screws — metal screws driven into the ground supporting a timber subframe.

Ground screws have become increasingly popular for garden buildings because they need very little site preparation, install quickly, work well on sloping or uneven ground, and can be adjusted to level. Concrete remains the more traditional choice and suits larger or heavier units. Which is right depends on your soil, slope, drainage and access — a groundworks contractor should assess rather than assume.

Whatever you choose, the base needs to match the unit's footprint precisely and be ready before delivery day.

The order to do things in

1. Check your garden actually works. Rear garden of your main residence, enough space, and — critically — think about access for delivery.
2. Get an access assessment. Find out early whether you need a crane. It changes your budget significantly.
3. Choose your unit. Confirm the finished height including base, and that it's built to habitable standard.
4. Sort the base. Groundworks contractor, concrete or ground screws, sized to the unit's footprint.
5. Notify the local authority. At least 14 days before work starts.
6. Book delivery and siting. Coordinate so the base is cured and ready before the unit arrives.

Common questions

Where to check the rules yourself

Don't take this page as the final word — verify against the source:

• gov.ie — for the statutory instrument and Department of Housing guidance
• Citizens Information — for plain-English summaries of planning rules
• Your local authority's planning department — the only place that can tell you how the rules apply to your specific site, and who you must notify anyway