Installing electricity in a shed or log cabin can allow for use throughout the year with heating and lighting. There are no shortcuts when it comes to a safe electrical installation, which should be carried out by a professional.
With the rapid increase in the use of garden buildings over the last few years, many of us are asking whether it’s possible to install electricity. An electrical supply to a shed can allow for lighting during the winter months or provide power to tools and other garden equipment. If the shed is going to be used as a workshop, electricity can power a small heater to keep warm when inside.
The challenge with installing electricity into a garden shed is that it’s often not a quick process. Laying a cable and installing sockets inside can be time-consuming, as well as expensive. For any electrical installation, a qualified electrician is required to ensure the work is completed safely.
For a quick solution, many will be wondering whether it’s possible to use an extension lead to power a shed, instead of installing sockets. Let’s take a look at our recommendations and the alternative options for powering a shed.
Can I run an extension lead to my shed?
It’s okay to use an extension lead to power a shed on a temporary and short-term basis. A permanent solution requires an SWA cable professionally installed.
If a shed requires temporary power, such as if you’re having a clear-out and require lighting, it’s fine to use an extension lead. Another example would be using power tools on a temporary basis for a project that also needs an electrical supply at the shed. During all of these, the extension lead can be turned off and wound up when not in use.
However, for permanent and frequent use, such as heating and lighting, an extension lead is not suitable. Anything that requires the extension lead to be permanently connected and left in position would be better served with an electrical installation.
Extension leads are designed with temporary use in mind and permanent use could push them above their designed operating conditions, leading to safety issues.
Challenges of powering a shed with an extension lead
Extension leads are great for powering garden equipment such as mowing the lawn during the summer. But they can pose a number of challenges when left out permanently, as would be the case when used to power a shed.
The outer insulation on the cable of an extension lead is designed to protect against damage that could expose the live wiring. Being left exposed to the sun for an extended period over many months can lead to the UV & weather conditions beginning to break down the cable.
While burying the cable underground may sound a good alternative, this can also lead to further challenges. Underground, the cable is vulnerable to attack from insects and rodents that can soon eat through the outer insulation, potentially leading to over-heating. An underground cable can also not be inspected regularly, making it difficult to ensure the cable is in full working order. Whilst you know where the cable is now, someone else in the future may not and could begin digging and cut through the thin outer insulation of the extension lead. If the cable is not rated for direct burial, it is not suitable for putting into the ground.
An extension lead cable running down the garden doesn’t look great and also creates the risk of tripping over. While you may be aware of the cable, anyone else, such as kids playing could easily trip over and injure themselves. The cable could also become damaged and strained from frequent knocks and being stood on regularly.
Each extension lead will also have a power limit, overloading the extension lead with lots of items at the same time can cause over-heating. The safest way to use an extension lead is to only take it out when it’s needed for temporary use. Once it has been used, the extension lead should be switched off and put away until the next time it’s required.
What about building regulations?
Installing electricity to an outbuilding such as a shed falls under part P of the building regulations. While using an extension lead temporarily does not fall within this scope, any permanent installation will.
Under part P, the electrical installation of a consumer unit, fuse box, new circuit or alterations to an existing circuit is notifiable. Therefore the work will need to be inspected and approved by a building control body if the installer is not registered. An installer registered with the ‘competent person scheme’ can self-certify with building regulations.
Any electrical installation that has not been certified could add challenges if you come to sell the house in the future. Unsafe installations could also lead to over-heating or a fire that could be blamed on not following building regulations.
Alternative ways to power a shed
Installing a permanent electrical supply into a shed is possible and recommended if you require a frequent power source. There are several options to consider including running an underground cable from the main property.
Steel wire armoured cable
The correct way to install electricity in a garden shed is to use a steel wire armoured (SWA) cable. Unlike an extension lead, the armoured cabled is designed to protect the live wiring from damage while in the ground. If the cable is hit by a person digging in the future, the steel wire will protect against the cable splitting open. The steel wiring also prevents rodents from eating through the cable while it is in the ground.
The cost of armoured cable can be expensive and it is purchased by the metre. A shed further away from the house can cost significantly more to get electricity to if a lot more armoured cable is needed. A qualified electrician is required for the installation and they will be able to supply the cable as well.
The armoured cable is usually hidden unground and will require digging a trench to lay the cable into. To save costs, you can dig the trench before the electrician arrives. It’s common to bury the cable 60cm deep but check with the electrician first.
The armoured cable will connect directly to the fuse box in the house and terminate into a consumer unit inside the shed. Due to the cable thickness, it’s not possible to terminate into a plug and will require a suitable enclosure etc at each side. Different thickness options are available and an electrician will recommend a suitable size based on the power requirements. This type of installation can allow for multiple plug sockets inside a shed so there is plenty available to power a range of equipment at the same time.
For most use cases, mains power electricity will be required. But if just a small amount of electricity is needed, a solar panel on the shed roof could be suitable. Solar panel kits can be purchased and fitted onto the roof without needing professional installation.
Different power ratings are available up to 200W. Solar panels are great if only light is required in the shed and it is not being used to power any garden equipment. LED bulbs are very power efficient and the solar panel can provide enough power to light up the interior of a shed.
A battery is fitted with solar panels to store the electricity that has been collected throughout the day. When the lights are turned on, the power comes from the battery that has been charging from the solar panels.
Difference between sheds, cabins & other garden buildings?
Despite their structure and use varying slightly, getting electricity into any garden building is similar. For all of them, an extension lead is only a temporary solution and an armoured cable should be fitted from the house to the outbuilding for permanent use.
For log cabins, garden rooms and summerhouses, their use will often require more electricity. If the building is being used as a garden office or bar, a higher power requirement will be needed. An electrician may use a thicker cable that is suitable. Electric heaters are one of the biggest sources of electric use in a garden building and can use several times as much electricity as other common items.
Insulated garden buildings can allow the cabling for sockets to be hidden away inside the wall. During construction, a first fix can be carried out where the cabling is put into position before the insulation and interior wall lining is finished. The result is a clean install without the need for trunking to each socket.
In summary, an extension lead can be used to power a shed, but only on a temporary basis. For permanent electricity, an alternative power source is required. Leaving an extension lead in position for an extended period could result in damage to the cable or injury from tripping over.
A steel armoured cable is the best way to get electricity to a garden building. The installation should be completed by an electrician to ensure it is safe and meets building regulation requirements.