Multigenerational Living in Ireland: Building a Garden Home for Parents

Multigenerational living in Ireland increasingly involves building an independent, detached granny flat in the rear garden rather than extending the main house. Under S.I. No. 340/2026, garden dwellings up to 45 m² are exempt from planning permission, allowing families to house ageing parents close by while maintaining privacy for everyone.

Why choose a detached garden unit over a house extension?

A detached garden unit gives both generations complete privacy and independence, avoiding the disruption of a major house extension.

Building an extension often means months of dust, noise, and living in a building site. You lose the use of your kitchen or living room, and the daily routine of the entire household is interrupted. A detached unit keeps the construction activity at the end of the garden. Your main home remains entirely untouched during the process.

It also provides a clear physical boundary that supports healthy family dynamics. Your parent gets their own front door, kitchen, and living space, allowing them to maintain their independence. At the same time, you keep your family home intact for your own children and daily life. You are close enough to provide care and support instantly, but separate enough to avoid living on top of one another.

We build these units using ICF (Insulated Concrete Formwork). This involves pouring a reinforced concrete core on site between two permanent layers of insulation. The result is a solid, permanent concrete home, not a temporary timber or steel structure. It feels exactly like a traditional house, offering excellent soundproofing and structural strength.

Do I need planning permission for a granny flat in Ireland?

You do not need planning permission for a detached garden dwelling up to 45 m² if you meet the conditions of S.I. No. 340/2026, effective 27 July 2026.

This specific exemption makes granny flats a highly practical option for families exploring multigenerational living. By removing the planning process, you save months of waiting and uncertainty. To qualify for this exemption, which currently runs until 31 December 2030, you must meet these exact rules:

• The unit must be located in the rear garden of the main home.
• At least 25 m² of private open garden space must remain after construction.
• The unit must have its own separate entrance.
• The owner of the property must live in the principal dwelling.

If your planned build exceeds 45 m², or if you do not meet all the criteria above, you will need to apply for standard planning permission. Even with the planning exemption in place, you must still comply fully with Building Control regulations, fire safety standards, and BER requirements. The structure must be built to the same standard as any new residential home in Ireland.

How much does a garden home cost?

Nua Living offers four fixed-price sizes starting at €69,000 plus VAT at 13.5% for a 25 m² studio, excluding site works, connections, and professional fees.

Knowing the exact cost of the building helps you budget accurately for the project. Our prices include the architectural design, the physical build, and full project management of the structure itself. We provide four distinct sizes to suit different garden dimensions and family needs.

The 45 m² option is particularly popular because it maximises the space allowed under the upcoming planning exemption. The 48 m² two-bedroom unit requires planning permission but offers extra space for a carer or visiting family members.

Remember that site works, utility connections, and professional fees are priced separately. Site works include clearing the ground, levelling, and laying the foundations. Connections involve trenching and piping for water, electricity, and sewage back to the main house or public mains. Because every garden has different soil conditions and distances to utilities, these costs are calculated after a site assessment.

How long does it take to build an ICF modular home?

The on-site structural build takes just 5 to 10 days once the foundations are ready.

Before the physical build begins, you need to allow time for the initial design phase, confirming your planning eligibility, and preparing the site. Once the groundworks and foundations are complete, the ICF construction method allows for rapid assembly. The hollow insulation blocks are stacked quickly, and the concrete is poured directly into the core.

Because the concrete cures inside the permanent insulation layers, the walls go up much faster than traditional block-laying. This speed reduces the amount of time builders spend in your garden.

This method also ensures exceptional energy efficiency, which is vital for keeping running costs low for an older parent. Ireland's nZEB minimum standard is BER A2. Nua Living homes are designed to reach BER A1–A0. The continuous layer of insulation eliminates cold bridging, making the home incredibly warm and comfortable year-round.

What are the steps to start a multigenerational living project?

The first step is assessing your garden space to confirm it meets the 25 m² remaining space rule and has suitable access for construction.

You need to measure your rear garden carefully. The new unit will take up a specific footprint, and you must ensure enough private open space remains for the main house. You also need to consider how builders will access the rear garden to pour foundations and deliver the ICF materials.

Next, you should review the utility connections. The new dwelling will need to connect to your existing water supply, wastewater system, and electricity. A professional assessment will determine the most direct and cost-effective route for these trenches.

Finally, you select the unit size that fits your parent's needs and your garden's capacity. We manage the process from that point forward, handling the structural design and the complete build.

Frequently Asked Questions

Can a granny flat be delivered on a lorry?

No. Nua Living builds permanent homes on site using ICF (Insulated Concrete Formwork). They are not prefabricated timber or steel boxes delivered on a truck.

Does the planning exemption apply immediately?

The exemption under S.I. No. 340/2026 comes into effect on 27 July 2026 and runs until 31 December 2030.

Can I rent out the granny flat to a stranger?

Under the planning exemption rules, the owner must live in the principal dwelling. The exemption is designed for family use, such as housing a parent, rather than commercial rental.

Are these units warm enough for an elderly parent?

Yes. Nua Living homes are designed to reach BER A1–A0, exceeding Ireland's nZEB minimum of BER A2. The ICF construction provides excellent insulation and eliminates cold draughts.

Ready to explore your options?

The best way to start is by confirming your garden's eligibility and getting a clear picture of the total costs. We offer a free, no-obligation site visit to assess your space, check utility routes, and discuss your family's needs. Check if your garden qualifies and get a fixed price today.