Garden Rooms with a Bathroom in Ireland: Costs, Plumbing & What to Consider

A garden room gives you somewhere to work, exercise or enjoy a little space away from the house. Adding a bathroom can make that space much more convenient, especially when you spend several hours there at a time.

But choosing a garden room with bathroom facilities involves more than finding room for a toilet and basin. Water supply, drainage, hot water and ventilation all need to be considered, alongside the building’s layout and intended use.

For some households, a compact toilet and hand basin will do the job. Others want a shower after a workout, or are considering accommodation for a family member. Those uses can lead to different designs, budgets and planning requirements.

This guide explains the decisions to make before ordering, what affects the cost and how to get a quote that covers the complete project.

Choosing your bathroom facilities

Start with how you will use the building on an ordinary day. A garden office used throughout the working week has different requirements from a gym used for an hour in the evening.

A garden room with toilet facilities may be all you need if the priority is avoiding repeated trips back to the house. Adding a shower is worth considering when you can identify a regular use for it.

Be clear about any intention to sleep in the building from the beginning. A bathroom does not, by itself, make a garden room suitable or authorised for residential occupation.

How much does a garden room with a bathroom cost?

The total budget has three main parts: the garden building, the bathroom fit-out and the work needed to connect the services. Check all three when comparing quotations.

The garden building

As examples from Loghouse’s Studio Eco range, published prices checked in September 2026 are:

These are starting prices for the building packages, not completed garden rooms with bathroom facilities. The product pages identify plumbing and electrics as additional work. Finish choices also affect the price.

The listed packages include assembly and ground-screw foundations where ground conditions are suitable. Confirm the specification, bathroom layout and any site-related additions for your chosen model before ordering.

Bathroom fitting and connections

Guides to building costs published by Loghouse for its Dublin Studio product.

These are indicative categories for quotes – the actual work categories will be confirmed following a site survey. The quotation will provide clear details of the work to be done and any overlap, in addition to VAT.

Remember to ask for the final VAT-inclusive offer price for the specific project (building, fixtures and connections) in question.

Why the same bathroom can cost more on another site

The cost for the same bathroom fittings on a different site will also be influenced by the location of the bathroom in relation to the rest of the site.

A connection to a short route across accessible ground is a different job to a connection under a finished patio, requiring consideration of drainage levels, access to excavations, making good of surfaces, etc. Likewise, the need to pump sewage may add significantly to the cost of connections.

Two different households with identical bathrooms will have differing costs for the bathroom alone. For example, one household may have short runs of accessible ground, whereas the other has longer runs across lawn. The cost of lifting and reinstating the path would not be included in a comparison of the bathroom fittings alone.

Water supply and drainage

If possible, establish where water will come into the room and where wastewater will go before deciding on the position of the garden room; the most attractive corner of the garden may not be the easiest to connect to.

Bringing water to the room

The supply route should be assessed by the installer for the garden room to determine the most appropriate route, adequate water pressure and flow, isolation to the supply and adequate protection against freezing.

A decision must also be made regarding hot water facilities for hand washing or regular showering. This will influence the overall system design, and the installer must ensure that this is all properly coordinated with the main electrical supply to the building.

Taking wastewater away

If you intend to fit a toilet, the connection type to the foul-water sewer will need to be a foul-water connection, not a connection to a nearby rainwater drain as this can lead to untreated wastewater being put into the environment.

Your installer will assess the existing drainage for your garden room. If your existing drainage flows downhill through suitably sized pipes, then this will be the preferred method of drainage. If however, the levels in your garden prevent gravity drainage, then a pumping system will need to be considered and assessed.

There are a variety of wastewater lifting systems available for use with garden rooms which are equipped with WCs. These need to be suitable for the fixtures which are to be used as well as the discharge. Note the requirement for maintenance access, power supply and what to do in the rare event that the pump fails to operate.

Contact Uisce Éireann early in the development process if the proposed work involves a new connection to public water supply or wastewater assets or modifications to an existing connection.

Homes with a septic tank

Check if the current system will be sufficient for the intended use of the new garden room, and check the condition, capacity and suitability of the septic tank of the current treatment system and obtain a competent opinion as to whether any upgrades are required. The EPA’s domestic wastewater guidance can assist with the assessment and design of wastewater systems for homes.

Making the layout work

Floor plans for Garden Rooms with bathrooms show how both spaces will function after partition walls and fittings have been installed.

This plan needs to show the internal dimensions of the space, and how there will be room for the bathroom to open, for a person to stand at the basin and turn around, and for movement around the room.

Think about privacy when positioning the bathroom door and window, particularly in relation to a desk or seating area. Plan the lighting and storage too, with space to keep towels and cleaning products within easy reach without cluttering the room.

Think about how easily people can enter and move around the shower room. If someone has limited mobility, discuss their needs early so the doorway, shower access and layout can be designed to suit them.

It is also worth checking whether positioning the bathroom on the other side of the building would simplify the drainage connection. A small change to the layout could reduce the amount of excavation and pipework needed outside.

Ventilation, waterproofing and comfort

If you are adding a shower, plan the ventilation from the outset. SEAI’s guidance recommends mechanical extraction to remove moisture directly outdoors, helping to reduce condensation and mould. Ask your installer where the extractor will be positioned and how fresh air will enter to replace the air being removed.

The shower area also needs proper waterproofing beneath the tiles or other finishes. Confirm which waterproofing system will be used and whether it is suitable for the garden room’s construction. Particular attention should be paid to corners, joints and the points where pipes pass through walls or floors.

For comfortable year-round use, consider insulation and heating alongside the bathroom fittings. The room should feel warm on a winter morning and allow moisture to clear after a shower. Ask your installer how the plumbing will be protected against freezing during cold spells, especially when the garden room is not being used.

Planning considerations in Ireland

The intended use matters as well as the building’s size. Ireland’s exemption rules changed on 27 July 2026, and ordinary garden outbuildings and habitable garden dwellings fall under different provisions.

Garden rooms for use alongside the main home

Under the amended Class 3 exemption, qualifying garden outbuildings can have a combined floor area of up to 30 m². This total includes relevant sheds and other outbuildings already on the property. Conditions also apply to the building’s height, location, external finishes and the amount of private outdoor space left available.

The building must support the enjoyment of the main home, for example as a home office or hobby room. This exemption does not cover sleeping or residential accommodation.

A garden room with a toilet is therefore not automatically exempt because it falls within the size limit. Its intended use, design and position must also meet the relevant conditions. Read the Class 3 regulations.

A garden bedroom with bathroom facilities

If you intend to use the garden building for sleeping or as a home, make this clear at the design stage so the appropriate planning requirements can be checked.

The separate Class 3A exemption provides for qualifying garden dwellings of 32–45 m². Relevant existing Class 3 outbuildings also count towards the 45 m² combined limit, so the space available for a new dwelling may be reduced.

Conditions cover utility connections, access, remaining garden space and the dwelling’s relationship with the main house. You must notify the planning authority at least 14 days before work begins, and the dwelling cannot be used for short-term letting under this exemption.

These are some of the key requirements, rather than a complete checklist. Adding a bedroom and bathroom does not automatically qualify the building for exemption—the full design and site must meet all applicable conditions. Read the Class 3A regulations.

Planning exemption also does not remove the building regulations and building control requirements for an auxiliary dwelling. The Department’s information note explains this separately.

Before committing to a design, have its intended use and site checked. Where exemption is uncertain, ask the local authority about a Section 5 declaration.

What to include in your quote

When comparing garden rooms with a toilet or shower, ask for an itemised quote that clearly sets out:

• The building, foundations and agreed internal layout.
• Bathroom fittings, installation and finishes.
• Water supply, wastewater drainage and any pumping equipment.
• Hot water, heating, electrical work and ventilation.
• Excavation and the cost of restoring lawns, paving or other affected surfaces.
• The total price including VAT, with any exclusions or separately charged work clearly identified.

Can the bathroom be ready for use at the same time as the main build of the garden room? Will there be separate stages of connection of all services? Who will be coordinating the various trades?

Frequently asked questions

Can I add a bathroom to an existing garden room?

In very rare cases it might be possible to add a bathroom to an existing garden room but it will always be subject to the same assessment criteria for a new build: suitable layout, sufficient structure, adequate service routes and intended use. When comparing like with like, be sure to include the cost of any additional works required to the main structure as well as the costs for the additional fixtures and fittings required for the bathroom.

Is a toilet and basin cheaper than a full shower room?

A toilet and basin installation needs much simpler bathroom fittings than a shower room, although you will generally need to cost the connection to external services in full regardless of whether you omit the shower.

Will a bathroom work at the end of the garden?

You can locate bathrooms at the end of the garden, but you’ll need to consider drainage levels, water supply, and access for installers. It’s best to check these factors before finalising a location.

Can I sleep in a garden room because it has a bathroom?

A bathroom installed in a garden room does not automatically mean that you can use the room as a bedroom, as it will need to comply with local planning regulations for the intended use.

Discuss your project with Loghouse

To create your ideal garden room with bathroom facilities, start with creating a brief that clearly outlines the intended use of the room, the facilities needed, and potential locations within the garden.

Explore our Eco Garden Room range and then speak to the team at Loghouse to discuss the various models and internal layouts and to organise a site visit to produce a specification and free quote for your proposed Garden Room. Please forward photographs, approximate floor dimensions and intended use.