Consumer Unit in Cupboard Dangerous? How to Box In?

There are a few things that you need to consider in order to establish if your consumer unit is safe or not. If you have not built the cupboard yet but wish to then there are other considerations too.

• Ventilation and Air Flow
• Accessibility and Working Space
• Is there a fire risk
• Wiring Regulations
• Materials of construction
• Allow sufficient space
• Provide Ventilation
• Consider Professional Installation

Ventilation and air flow: Consumer units generate heat, especially if there's an electrical fault. Proper ventilation is important to prevent overheating. If you enclose the unit in a cupboard, ensure there's adequate ventilation to dissipate heat. Also ensure that the consumer unit is not located in an airing cupboard with a hot water tank or boiler as this will add additional heat to the surroundings and prevent the consumer unit from being able to dissipate its own heat quickly and safely.

Accessibility and working space: Consumer units and fuse boxes need to be accessible for maintenance, inspection, and in case of emergencies. Blocking access to the consumer unit could impede the ability to turn off power in case of electrical faults or emergencies. When an electrical fault occurs, the electrician nearly always needs access to the consumer unit in the property. Access to the main switch is particularly important as this isolates the whole electrical installation and is necessary in an emergency to operate. 

This is difficult enough where furniture is required to be moved or possessions from the garage if the fuse box/consumer unit is installed out there. When the consumer unit is installed into a small cupboard, often access becomes nearly impossible and the cupboard may have to be destroyed in order to access the consumer unit and the wiring inside.

Is there a Fire Risk: We cannot ask if a CONSUMER UNIT IN CUPBOARD is dangerous without considering how it is installed. Poorly installed consumer units or enclosures that are not fire-resistant can pose a fire risk, especially if there's a fault or overheating. Is a plastic consumer unit illegal? This question and many more are answered in our massive consumer unit article here.
Consumer unit boxes should have a good fitting lid to them with all fixings intact such that the lid or face of the consumer unit is adequately secured once installed. If your consumer unit lid is missing, broken or has holes in it then it may require replacing, normally the consumer unit itself needs to be replaced if this is the case. Small holes can often be filled safely by electricians however.  

If you're planning to box in a consumer unit, here are some steps to follow to ensure safety:

Consult Local Wiring Regulations: Check your local electrical codes and regulations to ensure compliance. Different regions may have specific requirements regarding the installation and enclosure of consumer units. In the UK we adhere to B7671 wiring regulations and follow its guidance. Failure to do so could lead to failure to comply with the law and severe danger. The requirements of Part 5 of BS7671 on Selection and Erection of Equipment in particular must be adhered to. Your electrician will be best placed to advise you on the wiring regulations and any requirements that must be adhered to.

Suitable Construction Materials: Use fire-resistant materials to construct the enclosure. Materials like metal or fire-rated wood are commonly used. Ensure that the materials used are suitable for electrical installations. Using sub standard materials to construct an enclosure is likely to result in problems later on. Great care should be taken whilst constructing the enclosure not to drill into any cables whilst attaching the enclosure to the walls or ceiling. Surrounding a consumer unit and buried in the walls are very often a multitude of cables and installation of a boxing in enclosure can often lead to cable damage. If you are not sure if there are cables around your consumer unit that are hidden then contact your local electrician to advise.

Allow Sufficient Space: Some common sense is required here.  Ensure that there's enough space around the consumer unit to facilitate maintenance and cooling. Follow manufacturer guidelines for clearance requirements. We regularly see consumer units that have had to be modified or part of their lid removed in order for the consumer unit to be accessible because a cupboard has been built around the consumer unit and caused problems for access or working space to the unit itself. 
Also, don’t pile all your stuff on top of the consumer unit. Its not a good idea to completely cover an electrical enclosure and circuit breakers that generate heat and require some air flow in order to work safely. Ensure that the cupboard door of the enclosure doesn’t foul the consumer unit or prevent its cover from being removed. This is an all-too-common occurrence unfortunately.

Provide Ventilation: Install vents or grilles to allow airflow into the cupboard to prevent overheating. These vents should not compromise the fire resistance of the enclosure. If possible, ensure the cupboard is ventilated and not too small for the consumer unit. These units need to dissipate heat under normal working conditions and extra heat under fault conditions. Without adequate space around the unit there could be an increased risk of fire.

Consider Professional Installation: If you're unsure about how to safely box in the consumer unit, it's advisable to hire a qualified electrician to do the job. They can ensure that the installation meets safety standards and regulations. They will advise if boxing in the unit is possible or is likely to cause damage to wiring systems surrounding the consumer unit. Remember that cables are not always where you think they will be and there are safe wiring zones around electrical equipment and accessories that need to be adhered to! 

Is a consumer unit in cupboard dangerous then?

If you are still unsure if your consumer unit is safe or not then its best to consult an electrician that will be able to advise you if anything is necessary in order to improve safety. 

Most consumer units are ok in a correctly built cupboard but some cupboards are just not right for the consumer unit for all the reasons mentioned above.

Common Questions

Can an electrician move a consumer unit?

YES. Although, the cost may surprise you. Whilst an electrician can move a fuse box or consumer unit there is a good chance that the consumer unit will have to be swapped for a completely modern and regulations compliant consumer unit when it is moved. 

I promise its not us trying to make money and fabricate jobs, there is every chance that the wiring regulations will dictate a swap is necessary when extending several circuit and moving the installation from one place to another. There may also need to be a large junction box installed somewhere near the original consumer unit in order to safely enclose the extended cables. 

It is possible to completely remove any sign of a consumer unit and relocate without a junction box but this is likely to involve a lot or work and cost significantly more than having a junction box on display. Cables will need to be accessed from above and below the existing consumer unit and several junctions made under the floor or in the ceiling. 

Such junctions will also need to be compliant with the safety wiring regulations BS7671 and be maintenance free if they are not accessible. 

Can I fit a consumer unit myself?

The short answer is no. There are so many requirements in order to make sure that a consumer unit and the circuits connected to it are safe that there is no chance that anyone other than an electrician could safely install a consumer unit. 

Some understanding is needed here when considering what is involved in a consumer unit change. For instance, it is not simply removing an old consumer unit and screwing a new one to the wall. Where a consumer unit is changed, the whole wiring installation MUST be tested in accordance with BS7671 wiring regulations and the results recorded on an Electrical Installation Certificate. 

Such testing is only likely to be understood by a qualified electrician, not to mention the tools required to carry out such work are beyond the financial reach of the average DIY person. 

The installation itself contains certain requirements such as correctly torquing the circuit breaker and other connections within the consumer unit and this again is likely to only be safely carried out by an electrician. 

Do you need building regs to change a consumer unit?

A consumer unit swap needs to be notified to building control BY LAW and failure to do so could result in unwanted consequences. An electrician is likely to be a member of a competent person’s scheme such as the NICEIC and as a result, should be able to notify the work to building control for you.