Garden Home
FAQs.

A Garden Home is a permanent, detached dwelling located in the rear garden of an existing principal house.

“Permanent” excludes caravans, mobile homes and other temporary structures. “Detached” means separate from the principal house. “Compliant” means addressing both the applicable planning rules and the separate Building Regulations and Building Control requirements.

“Garden Homes can create smaller, independent homes within established communities while making thoughtful use of existing land, services and infrastructure.” — Cathal & Paul

Similar homes are known internationally by many names.

• Accessory Dwelling Unit (ADU)
• Backyard cottage
• Carriage house
• Coach house
• Garden cottage
• Garden suite
• Granny cottage or granny flat
• Guesthouse
• Infill house
• Multi-generational home
• Secondary suite or secondary unit
• Tiny home

A marketing name does not determine whether a structure is lawful to occupy as a dwelling in Ireland.

The Class 3A exemption came into operation on 27 July 2026. It can allow one qualifying permanent, detached auxiliary dwelling in the rear garden of a principal house without a full planning application.

This is not automatic permission for every garden or every 45 m² unit. Conditions cover matters including ownership and occupation of the principal house, planning history, floor area, existing garden structures, retained open space, height, boundaries, access, services, use and advance notification to the planning authority. Building Regulations and Building Control requirements still apply.

The exemption is time-limited: qualifying development must be commenced and completed within the statutory period ending 31 December 2030.

Start with a preliminary garden assessment →

Ireland has a substantial housing shortage and a continuing need for additional homes. The Housing Commission’s 2024 report estimated an underlying housing deficit of approximately 212,500 to 256,000 homes as of the 2022 Census. Later Department of Housing analysis of ESRI research indicated structural demand averaging about 44,000 homes annually from 2023–2030 and suggested that roughly 50,000 new homes a year could be required when unmet demand is considered.

Garden homes will not solve the housing shortage alone, but suitable, compliant projects can add well-located homes within existing communities.

“Ireland needs housing solutions at many scales. Well-designed Garden Homes can make a meaningful contribution, one suitable property at a time.” — Cathal & Paul

We will survey your garden, help you choose the right Garden Home, negotiate the best price, manage delivery and installation, and keep you in compliance with the regulations.

We aim to offer a flexible service, and you can choose some or all of the following.

Start with your free site review

As a broad early guide, complete project costs might range from approximately €70,000 to €150,000 or more. The actual figure depends on size, design, structure, finishes, site access and what the quotation includes.

We will confirm what is included and excluded: survey, design certification, foundation, transport, crane, services connections, kitchen, bathroom, heating, and furniture.

A habitable dwelling should not be compared with a garden office, playroom, cabin or other product that was not designed and compliant for permanent residential use.

Privacy should be considered from the first site layout, not added at the end. Options can include:

• Orienting the home and its principal windows to reduce overlooking.
• Locating entrances, terraces and paths carefully.
• Using suitable boundary treatments, fencing or lattice screening.
• Adding hedges, trees and layered planting where appropriate.
• Using obscure glazing, privacy glass or window film in suitable locations.
• Providing curtains, blinds and other internal screening.

The solution must also respect daylight, outlook, fire safety, access and any applicable planning conditions.

Not automatically. A new dwelling must address Part L of the Building Regulations and will require a Building Energy Rating where applicable, but its final rating depends on the complete design and verified construction.

High levels of wall, floor and roof insulation, airtightness, efficient heating and hot water, suitable ventilation, high-performance windows and doors, and renewable-energy systems can all contribute.

No. Some products that resemble homes are designed only as garden offices, leisure rooms or non-habitable cabins. Appearance, price or a supplier’s description does not establish compliance for residential use.

We will confirm that your garden home is compliant with planning and building regulations.

“A permanent home is too important for vague assurances.” — Cathal & Paul

Ireland’s Building Regulations are organised into Parts A to M, with no Part I. The relevant Technical Guidance Documents address:

The parts that apply and the required Building Control submissions, certificates and supporting records must be determined for the specific project by competent professionals.

Under Revenue’s current published guidance, a self-contained unit adjacent to—but not attached to—the main residence cannot qualify for Rent-a-Room Relief. A detached Garden Home should therefore not be advertised on the assumption that its rent will fall within the €14,000 relief.

“A Garden Home in a high-demand area can still offer an income opportunity without Rent-a-Room Relief. In Scenario A of our €20,000 annual-rent example, €16,212.80 remains after tax and PRSI, before cash expenses. Explore the assumptions in our Taxation Guide.” — Cathal & Paul

Read Revenue’s current guidance →

• Planning enforcement: unauthorised development or use may lead to enforcement, alteration, cessation of use or removal. Statutory time limits and exceptions are fact-specific, and retention is not automatic.
• Fire and building safety: inadequate escape, fire resistance, separation, structure or services can put occupants and neighbours at risk.
• Sale and finance: missing planning or compliance records can delay or affect a sale, mortgage, refinancing or estate administration.
• Insurance: cover depends on policy wording, disclosure, use and compliance. A claim may be disputed or refused where material facts were not disclosed or policy conditions were not met.

Start with a garden assessment →

The Class 3A exemption, in effect since 27 July 2026, makes adding a permanent, detached garden home to your rear garden more straightforward. No planning application is required where all the exemption conditions are met.

The exemption expires on 31 December 2030, and qualifying works must be commenced and completed within the relevant period. We strongly recommend exploring your options early so there is time to assess your garden, choose your home and arrange delivery and installation.

Check your garden