Do temporary buildings need an EPC?

A temporary building that will only be used for two years or less is exempt from the EPC rules in England and Wales. The harder questions are about portable and modular buildings that stay longer, site cabins, and temporary buildings that outlast their plan. For the general triggers that apply to permanent premises, see do I need a commercial EPC?

What does the temporary building exemption say?

GOV.UK's page on EPCs for business premises says you do not need an EPC if you can demonstrate that the building is "a temporary building only going to be used for 2 years or less". The legal source, regulation 5 of the Energy Performance of Buildings (England and Wales) Regulations 2012, covers "temporary buildings with a time of use of two years or less".

The government's guide to EPCs for non-dwellings describes the same category as temporary buildings with a planned time of use of two years or less. The word that matters is planned. The exemption looks at how long the building is intended to be used, which is why it pays to have that intention in writing at the outset: a project programme, a hire agreement or a planning permission that limits the period.

Is it a building for EPC purposes at all?

Before the two-year question, check whether the structure is a building in the EPC sense. Regulation 2 defines a building as a roofed construction having walls, for which energy is used to condition the indoor climate. The non-dwellings guide explains that this means fixed services for heating, mechanical ventilation or air conditioning, meaning services attached to the fabric of the building.

Hot water and electric lighting do not count. The guide says hot water does not condition the indoor environment and is not a trigger for an EPC, and that the same applies to electric lighting. So an unheated storage container or a cabin with lights and sockets but no fixed heating is not a building for EPC purposes, however long it stays.

Size can settle it too. GOV.UK exempts a detached building with a total floor space under 50 square metres, and the guide defines a stand-alone building as one entirely detached from any other building. A single detached cabin under 50 square metres is outside the rules on size alone, whatever its planned life.

Do site cabins and welfare units need an EPC?

Run through the tests in order:

1. Does it have fixed heating, mechanical ventilation or air conditioning? If not, it is not a building for EPC purposes.
2. Is it a detached unit under 50 square metres? If so, it is exempt on size.
3. Is its planned time of use two years or less? If so, it is exempt as a temporary building.

Only a structure that fails all three tests is inside the rules, and even then an EPC is only needed at a trigger point: when the building is erected, sold or rented out. A large, heated, linked cabin complex planned for a three-year project is the kind of case to check properly.

Do not confuse this with the Building Regulations. Schedule 2 to the Building Regulations 2010 exempts a building on a construction site that is used only during the works and contains no sleeping accommodation, and separately exempts a building not intended to stay where it is erected for more than 28 days. Those are Building Regulations exemptions with their own thresholds. The EPC exemption uses two years.

What about portable and modular buildings that stay longer?

Modular offices, temporary classrooms and similar units are not always temporary in the EPC sense. If one is planned to be used for more than two years, it does not fall within the temporary building exemption and is treated like any other building.

Approved Document L, the government's guidance on the energy rules in the Building Regulations for England, takes the same approach. It says portable or modular buildings with a planned service life of more than two years, whether on one or more sites, are not exempt from those energy rules. It also says placing an existing module on a new site counts as constructing a new building for Building Regulations purposes.

That matters because the EPC duty on construction applies when a building is erected. Under regulation 7A, the person carrying out the building work must give an EPC to the owner and notify the local authority, not later than five days after the work is completed. The non-dwellings guide adds that building control will not issue a completion certificate until it is satisfied this has been done. For new buildings generally, see EPCs for new commercial buildings.

Hire fleets are the grey area. Approved Document L treats a unit hired to several sites, each for less than two years, as needing to meet the energy rules because its overall service life is longer, and gives the hire agreement as an example of evidence of the planned time at each location. The EPC regulations only refer to time of use, without saying whether that means one site or the unit's whole life. If you supply or take on hired units that are heated and over 50 square metres, take advice rather than assume.

What if a temporary building stays longer than planned?

The exemption rests on a planned time of use of two years or less. Once the plan changes and the building is going to stay in use beyond that, the basis for the exemption has gone. From then on, treat it as an ordinary building: if it is sold or let, or forms part of premises that are sold or let, it needs an EPC like anything else on the site.

If a building was put up for a short project and then kept, check its position before any sale or letting of the site, rather than relying on paperwork from when it was installed.

Does a short lease make a building temporary?

No. The exemption is about the building's planned time of use, not the length of a lease. A six-month pop-up shop in a permanent unit is still a letting of a permanent building, and the EPC duty on renting out applies in the usual way.

MEES is different. The government's non-domestic landlord guidance says the minimum standard does not apply to a tenancy granted for a term certain not exceeding six months, unless the tenancy can be extended beyond six months or the tenant has already been in occupation for more than 12 months. That is a MEES rule, not an EPC exemption. The wider MEES position is on the MEES compliance page.

If your building does need a certificate, check what triggers the requirement and use the form on this page to request quotes from accredited assessors.

Sources

• Energy Performance Certificates for your business premises, GOV.UK, checked 19 October 2026
• Energy Performance of Buildings (England and Wales) Regulations 2012, regulations 2, 5 and 7A, legislation.gov.uk, checked 19 October 2026
• A guide to Energy Performance Certificates for the construction, sale and let of non-dwellings (updated 11 December 2017), Ministry of Housing, Communities and Local Government on GOV.UK, checked 19 October 2026
• Building Regulations 2010, Schedule 2 (exempt buildings and work), legislation.gov.uk, checked 19 October 2026
• Approved Document L, Volume 2: Buildings other than dwellings, 2021 edition incorporating 2023 amendments, GOV.UK, checked 19 October 2026
• Non-domestic private rented property: minimum energy efficiency standard, landlord guidance (last updated 5 May 2026), Department for Energy Security and Net Zero on GOV.UK, checked 19 October 2026

Common questions

Does a marquee or event structure need an EPC?

Not for a short event. A structure used for two years or less falls within the temporary building exemption, and if it has no fixed heating, mechanical ventilation or air conditioning it is not a building for EPC purposes in the first place.

Is the 28-day rule for temporary buildings the same thing?

No. The 28-day rule is a Building Regulations exemption for buildings not intended to stay where they are erected for more than 28 days. The EPC exemption is separate and uses a planned time of use of two years or less.

Who provides the EPC for a new modular building that is not temporary?

Regulation 7A puts the duty on the person carrying out the building work. They must give the EPC to the owner and notify the local authority not later than five days after the work is completed.

What evidence shows a building is only planned for two years?

Anything that records the intended period at the outset helps, such as a project programme, a hire agreement or a time-limited planning permission. Approved Document L gives the hire agreement as an example of evidence of planned time of use at a location.

Related guides

• Do listed commercial buildings need an EPC?
• Do places of worship need an EPC?
• Do workshops, industrial sites and farm buildings need an EPC?