Garden office electrics

The garden office electrics will play a key part in the usability of your building as a home office. This article covers the basic electrical set up and explains what is asked of you, the customer, but we advise you also read our lighting, heating, communications and security guides before deciding on your electrical specification.

Most garden offices come pre-wired as standard


Garden-office-electricsAll but the most basic garden office designs come as pre-wired units –  a garden office wouldn’t be very functional without an electrical supply!

In most instances garden office designs are built off site and then the modular components are but together on site. As part of this pre-assembly process all the cables for the power, light and heat are incorporated within the structure of the building, so that when the building is on site the system just needs connecting to the mains supply and testing by a qualified electrician.

A garden offices electrics need to comply with Part P of the Building Regulations

It is a legal requirement that any domestic electrical work is undertaken by a qualified electrician, and this includes connecting the electrical system of your garden office to your house’s mains supply.

Depending on the supplier you choose they may undertake this connection as part of the price and package they offer you. In many cases though the connection to the mains supply is a job for you the client to organize and pay for, this is because most companies don’t send an electrician to site with the installation team.

Whats involved in connecting the garden offices electrics to the mains supply?

A garden office is connected to the electrics of the house by a heavy duty armoured cable. This cable needs to be buried underground – approximately 500 – 750mm deep, a hazard tape is buried above it and then the trench is often back filled with stone before finally replacing the earth. This is to ensure that the cable is more than a spades depth deep, and if anyone should dig in the area in the future they will be warned of a cable by the stone and hazard tape.

Depending on how far your garden office is from the house will effect how long a trench will need to be dug, this is a labour intensive business, and if you want to cut down on costs maybe a job you could undertake yourself, but speak to the electrician who will advise you on the ideal depth of the trench and the route it should take.

Your electrician will connect one end of the armoured cable to the consumer unit in the office and the other end to your main fuse board in the house. The electrician will also add a earth rod to the garden office, this is inserted into the ground near the building and has a green and yellow cable running from it.

Once the office is connected to the mains the electrician will test the circuits, and once everything is complete will issue with a certificate showing that everything has been tested and complies with the Building Regulations.

A garden offices electrical connection is often a hidden cost

Because you get so much from a garden office supplier i.e. a whole building, and they are sold as complete packages, it is easy to overlook the cost of connecting the electrics, but it is a key aspect of making your building functional.

It is difficult to estimate the costs involved as the distance the office is from the house will impact on the amount of armoured cable needed, also you may need a circuit added to your fuse-box depending on your electrical set up. To give you a ball park estimate we would allow between £500 and £1000 for this job.

Garden office electrical specification

A lot of thought has been given to the basic electrical specification of garden office designs, designers have worked out the optimum number of sockets, lights and heating output for the size of the building and these make up the standard electrical pack offered.

It is worth thinking at the design stage if this standard specification is enough for you. Do you need a few extra power sockets for all your gadgets, or do you need to add data cabling to the spec? Adding extra sockets, lights and data cabling is relatively easy and cost effective at the design stage compared to when the building is finished.

High spec garden office designs are often finished with chrome or brushed steel face plates on the sockets and switches, but unless you see this stated in the specification assume the switches are white plastic – just like those used in a  house.

Most garden office designs today have flush electrical  fittings i.e. the face plates are flush with the wall and the cables hidden within the structure of the building, but there are still a few designs on the market that use surface mooted systems.

Some garden office electrical systems are in surface mounted track systems

Some garden office electrical systems are in surface mounted track systems

Surface mounted systems come in two versions a track system that runs horizontally along the wall – rather like you see in commercial buildings and hospitals, all the sockets and switches are located in this track, with the cabling behind. This isn’t the most aesthetic of finishes but does have the benefit that you can easily add sockets to the system as the cabling is accessible.

Some suppliers use surface mounted systems, the plastic conduit is visible and the sockets stand proud of the wall

Some suppliers use surface mounted systems, the plastic conduit is visible and the sockets stand proud of the wall

The second system involves running a narrow conduit which contains the cables around the building, leading to the sockets and switches which sit proud on the wall, again not considered the most aesthetically pleasing option today when clean lines are favored.

This article covers the basics of the electrical system of a garden office, we recommend you read our lighting, heating, security and communications guides which are all important aspects of your electrical specification.