Garden office guide: setup, costs, electrics and broadband

What size you need

• One person, desk only: 7 to 9 m².
• One person with a sofa or meeting chair: 12 m².
• Two people, or office plus gym: 16 m² or more.

Here's a 4 × 3 m office with a desk facing the side wall, out of the glare from the doors:

Planning for a garden office

A home office is one of the uses the garden room exemption is designed for, including working from home for your employer. It must meet the usual rules: up to 30 m², 25 m² of garden left, behind the house and within the height limits. See the planning guide.

The line is crossed when it becomes a business premises, with clients visiting, staff working there or signage. That needs planning permission. See running a business from a garden room.

Broadband and Wi-Fi

Wi-Fi from the house often struggles to reach the end of a garden, especially through brick or block walls. Options, from most to least reliable:

1. Ethernet cable laid in the same trench as the power supply, with a Wi-Fi access point in the office. Outdoor-rated cable in a duct, run while the trench is open, costs little.
2. Point-to-point wireless bridge: a pair of small outdoor antennas between house and office.
3. Mesh Wi-Fi with a node near the back of the house.
4. Powerline adapters, which work only if the office is on the same electrical supply, and results vary.

Power, lighting and heat

• Electrics must be done by a registered electrical contractor, who gives you a completion certificate. It is the law. See electrics for a garden room.
• Plan sockets at desk height for monitors and chargers, plus one for a heater.
• Use daylight LEDs for winter afternoons, and an outside light on the path.
• For heat, an electric panel heater on a timer, or an air-to-air heat pump if you also want cooling in summer. See heating a garden room.

Comfort for a full working day

• Glare: place the desk side-on to the main glazing, not facing it or with your back to it.
• Summer heat: a south-facing glass front overheats. Blinds, roof overhangs or tinted glass help.
• Sound: for video calls, add soft furnishings and acoustic panels so the room doesn't echo.
• Ventilation: trickle vents or a window that opens, to keep air fresh and avoid condensation.

What it costs

Add electrics, heating and a base if they aren't included. See extras and hidden costs.

Tax relief for working from home

You can't claim tax relief on the cost of building a garden office. But if you work from home for an employer, Revenue lets you attribute 30% of your electricity, heating and broadband costs to remote working, apportioned by the days you work from home. Your employer can instead pay a tax-free allowance of up to €3.20 a day. If they pay less than your costs, you can claim the difference as Remote Working Relief.