Garden Homes

Occupancy

Who can live in it.

This is the paragraph most people haven’t read, and it decides more about whether a garden home suits you than the size of it ever will. It is also the reason we would rather tell you now than after you have spent the money.

What the regulation says

Occupied in conjunction with the main house.

“The detached dwelling may only be occupied in conjunction with the main dwelling house and cannot be sold or subdivided separate to the principal dwelling.”

S.I. No. 340 of 2026 · Class 3A, paragraph 3

“The detached dwelling may not be used for the purposes of Short Term Letting.”

S.I. No. 340 of 2026 · Class 3A, paragraph 19

Those are the words, not our summary of them. A garden home built under this exemption is tied to the house in front of it. It is not a second property on the same site, and it never becomes one.

What it is very well suited to

The house that grows when the family does.

Read paragraph 3 again and what it describes is a household spreading out. That is not a limitation on the idea. For most of the people who enquire with us, it is the idea.

  • An adult son or daughter who can’t get near a deposit

    Their own front door, their own kitchen, their own life — without the two grand a month that would otherwise be going to a landlord, and without moving to the far side of the county to afford it.

  • A parent who shouldn’t be on their own any more

    Independent, with their own space and their own routine, but close enough that somebody notices if the lights don’t go on. For a lot of families this is the alternative to a conversation nobody wants to have.

  • Downsizing without leaving

    Some people build it and move into it themselves, and the main house takes the family. Same address, same neighbours, same view, far less to heat and maintain.

  • The space the house never had

    Somewhere to work that isn’t the kitchen table, a room for a family member home for a stretch, or the guest space that stops visitors taking over the house.

And it stays part of your property.

Because it cannot be sold or subdivided away, the value it adds is added to your home rather than split off from it. For a family planning to stay put, that is the point rather than a drawback.

Be straight about the limits

What it is not.

  • Not a short-term let

    Paragraph 19 rules it out in terms. No holiday lets, no short-stay platforms. If that was the plan, this exemption is not the route.

  • Not a separate property to sell on

    It cannot be sold or subdivided away from the principal dwelling. It is part of your home, permanently.

  • Letting it to a tenant is a question, not a given

    “Occupied in conjunction with the main dwelling house” is the wording, and how far it stretches to a long-term letting to someone outside the household has not been settled. Anyone telling you flatly that you can rent it out is going beyond what the regulation says. If rental income is the reason you are building, tell us at the start and we will set out exactly where that stands for your situation before you commit a cent.

We would rather lose the job than get this one wrong.

A garden home built on the assumption of rent that turns out not to be permitted is a very expensive mistake, and it is the homeowner who carries it. This is the sort of thing our exemption work is reviewed for, and it is why we ask what a unit is for before we talk about what it costs.

Money changing hands

If anyone pays you to live there, tax follows.

Whatever the arrangement ends up being, the moment money is paid for occupation there is a tax position attached to it, and it is not one we can answer for you. What we can do is point out the assumption that catches people.

Rent-a-Room Relief: announced in Budget 2027, not yet law.

Budget 2027 (6 October 2026) announced that Rent-a-Room relief will extend to new garden homes of 32 to 45 m² built under the exemption, with a tax-free limit of €16,000 a year from 1 January 2027. Until the Finance Act passes, it is an announcement. Do not budget on it until it is law and your accountant has confirmed it applies to you. More on Rent-a-Room relief for garden homes →

Beyond that, we are not tax advisers and we will not pretend otherwise. Rates, bands, reliefs and what is deductible all change, and they all depend on your own income and circumstances. Before you count on any figure, put it to Revenue or to your own accountant. That is not us passing the parcel — it is the only answer that is actually right for you.

Read it for yourself

The regulation, not our summary of it.

Everything on this page is quoted from or drawn out of the statutory instrument itself. It is short, it is in plain enough English, and it is worth twenty minutes of anyone’s time before they spend this kind of money.

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