You have found out that a solar installation on your house was never notified to Building Control, and now you want retrospective Building Regulations approval for the solar panels. You cannot buy a certificate after the fact the way an installer self-certifies on the day of the job. What you can do is apply to your local authority Building Control for a regularisation certificate, the formal route for signing off work that was carried out without consent. It is not automatic, and it is not only a job for your electrician.
The mistake most people make is treating this as one problem, usually the grid connection. It is really three separate tracks: the Building Regulations side (the electrical connection into your consumer unit), the Distribution Network Operator side (telling the network you have generation), and the structural side (the weight and fixings of the panels on your roof). Sort them in that order and each track has a clear owner and a clear fix.
The AC connection into your consumer unit is the notifiable part. Fix: a regularisation certificate from local authority Building Control.
A separate body from the council. G98 (under 3.68 kW AC): file the late notification yourself. G99 (larger systems): contact the DNO about the existing connection, not a simple late form. Building Control does not tell the DNO.
The roof has to carry the load. Usually a requirement, not a separate application, but be ready to evidence it if asked.
Can you get retrospective Building Regulations approval for solar panels?
Yes, within limits. For solar electrical work carried out on or after 11 November 1985, you apply to your local authority Building Control for a regularisation certificate under Regulation 18 of the Building Regulations 2010. They inspect the work, can require you to open up or test parts of it, and issue the certificate only once it complies. You cannot self-certify it after the fact.
Three things about that certificate are worth knowing before you start. It is available only from the local authority Building Control body, not from a private registered building control approver, because only the council can regularise past work. It covers Building Regulations, not planning, so it does nothing about any separate planning issue. And Regulation 18 states plainly that the certificate is “evidence (but not conclusive evidence)” that the work complies, so it settles the paperwork rather than guaranteeing the installation is beyond question.
First, inventory what you actually built
Before you phone anyone, write down the as-built system. Building Control and any electrician you bring in will ask for the same details, and having them ready shortens every conversation.
- Inverter make, model and AC rating, plus its ENA type-test reference if you have it.
- Panel count and total DC capacity in kilowatts.
- How the AC side reaches the consumer unit: a new dedicated circuit and breaker, or something else.
- Whether a battery is part of the system, and where it sits.
- The roof fixing type and whether the panels are on a pitched or flat roof.
- The install date, which decides both the enforcement window and whether the work falls after the 1985 cut-off.
- Any paperwork you were handed: an Electrical Installation Certificate, MCS certificate, or a DNO acceptance letter.
That last line often changes the picture. Many people who think nothing was ever done find a DNO letter in a drawer, or an installer’s certificate that was never passed to Building Control. What is missing is usually the building-regs sign-off, not every record.
Which part of a solar install was notifiable in the first place
In England and Wales the Building Regulations trigger for solar is the electrical connection, under Part P. Adding a new circuit at the consumer unit is notifiable electrical work. Mounting the panels, running the DC strings and siting the inverter are not, on their own, a separate Building Regulations application. If the job also replaced the consumer unit itself, that was separately notifiable in its own right.
So when a survey or a solicitor says there are “no Building Regulations for the solar panels,” it almost always means the electrical connection was never certified, not that the panels themselves are unlawful. That matters, because it points the fix at the right place: the consumer-unit connection and its certificate, not the racking on the roof.
The roof still has to carry the extra load under the structural requirements, and Building Control can ask you to show that the fixings and the roof structure are adequate. For a normal pitched-roof domestic array that is usually a question you answer with evidence rather than a second application, but do not assume it away if your roof is unusual or the array is large.
The regularisation route, step by step
Regularisation is a real, defined process, not a favour. Work it in this order.
- Call local authority Building Control first. Describe the system before you apply. They will tell you their fee, what evidence they want, and whether they can act on an installation this old.
- Submit the regularisation application with a description of the work and any plans you can produce, plus the fee. Council fees vary widely, often a few hundred pounds for small domestic electrical regularisation and sometimes more; get the current figure from your own authority before you budget.
- Provide electrical test evidence. Building Control officers do not usually test wiring themselves, so for the electrical work they will want an inspection and test report from a registered electrician. Some authorities only accept a report from a contractor on their own approved list, so ask before you pay for one.
- Expect them to open up covered work. Regulation 18 lets the authority require you to lay open the work, make tests and take samples so they can judge compliance. Be ready for that access.
- Do any remedial work they specify. If the installation does not meet BS 7671 or the structural requirements, you fix it first. There is no version of this where a non-compliant system is certified as-is.
- Receive the regularisation certificate once the authority is satisfied. Keep it with the rest of your pack.
Be honest with yourself about the total. You are paying the council fee, an EICR from a registered electrician, and whatever remedial work the inspection turns up. The remedials are the wildcard: if the original work was substandard, regularisation can cost more than the install ever saved, and it can force you to alter or redo the work. That is the inspection doing its job, not the process failing.
There is no fixed statutory timescale for a regularisation certificate. Once you apply, the pace is set by how quickly Building Control can schedule an inspection and how much remedial work the EICR turns up, so treat it as several weeks rather than a same-week fix. That timing is exactly why the regularise-versus-insure decision matters when you are mid-sale, and it is covered below.
The evidence only a professional can produce now
Some documents you can gather yourself. Others can only come from a qualified person, and knowing which is which stops you wasting time.
The original Electrical Installation Certificate can only ever be issued by whoever carried out and tested the work at the time. If you never got one and cannot get one, that door is closed. The realistic instrument now is an Electrical Installation Condition Report, an EICR, from a registered electrician. It reports the current condition of the installation and codes any faults, and it is the evidence Building Control usually leans on to decide whether the electrical work can be regularised. There is no single national form that says “submit an EICR”: your own Building Control team sets the evidence list, and some authorities ask for more than others. An EICR is not itself a Building Regulations certificate, and it does not replace the regularisation application; it feeds it.
If the system includes a battery, the bar is higher again, because battery storage in a dwelling is covered by the fire-safety rules in BS 7671 Amendment 4 and PAS 63100, including where the battery can sit. If your roof loading is ever questioned, the sign-off that carries weight is from a structural engineer, not from you. Treat both as jobs to hand over.
The DNO side is a separate fix
Your Distribution Network Operator is a different organisation from the council, and Building Control approval does not notify them. If the generation was never registered with the DNO, that is its own task, and a homeowner can do it without an installer.
For a single-phase system up to 3.68 kW AC the route is G98, which is connect-and-notify: it is meant to be filed within 28 days of commissioning, but if you are already past that, a late notification is still far better than leaving the network with no record. Above 3.68 kW AC the route is G99, which is normally an apply-and-approve process before connection; regularising an existing larger system is a conversation to have directly with your DNO. Either way, the DNO record and the Building Regulations certificate are two different pieces of paper, and you need both if both were skipped.
One more piece of paper that regularisation does not fix is MCS. An MCS certificate can only be issued by an MCS-certified installer at the time of the job, so a system that was never MCS-certified cannot be certified after the fact, and that closes the standard Smart Export Guarantee route for paid export. Regularisation settles Building Regulations, not MCS or export payments, so treat that as a separate question if getting paid for export matters to you.
What happens if you leave it
Contravening the Building Regulations is a criminal offence under section 35 of the Building Act 1984. The courts can impose an unlimited fine and, in principle, imprisonment. Prosecution is usually taken against the person who carried out the work, the installer or contractor, rather than a later owner, though it can fall back on you if you commissioned the work with no contractor in the frame. Separately, since 1 October 2023 a section 36 notice requiring you to alter or remove non-compliant work can be served up to 10 years after the work was completed, up from the old 12-month limit. That 10 years runs from the install’s own completion date, not from October 2023, so an older system can still sit inside the window. Routine council enforcement against a domestic solar array is uncommon, but sale and conveyancing make the missing certificate real even when nobody knocks on the door.
The bite most homeowners actually feel comes at sale. A buyer’s solicitor asks for the completion or compliance certificate for the electrical work, its absence stalls the conveyancing, and the usual fallback is Building Regulations indemnity insurance. Be clear about what that insurance does: it covers the cost of council enforcement, it does not make the installation safe or compliant, and it is typically voided the moment you approach the council yourself. That is why the calm move is to decide between regularising and insuring, rather than doing both in the wrong order.
Talk to your solicitor about Building Regulations indemnity insurance first, and do not contact the council. Approaching Building Control usually voids the policy, and regularisation rarely fits a live conveyancing timetable.
Regularise. Book the EICR, phone Building Control, do any remedial work, and hold the certificate. This is the route that actually fixes the record.
There is also the plain safety point. An uncertified consumer-unit connection is exactly the work Part P exists to control. Whatever you decide on paperwork, an EICR from a registered electrician tells you whether the thing on your wall is actually safe, which is the reason the rules are there in the first place.
Scotland and Northern Ireland are different
Regularisation under Regulation 18 and Part P are England and Wales rules. Scotland runs a building warrant system, and unauthorised work there is dealt with through its own late completion and retrospective warrant process rather than an English regularisation certificate. Northern Ireland has its own building regulations again. If you are outside England and Wales, ask your national building standards body what the equivalent retrospective route is before you assume any of the above applies.
Frequently asked questions
Can I get a Building Regulations certificate for solar panels after installation?
You can apply for a regularisation certificate, which is retrospective Building Regulations approval, from your local authority Building Control. It applies to electrical work done since 11 November 1985. The council inspects the installation, can require you to open up or alter parts of it, and issues the certificate only once it complies.
Is an EICR the same as a Building Regulations certificate?
No. An Electrical Installation Condition Report describes the condition of the wiring and codes any faults. It is not a Building Regulations sign-off. Building Control usually asks for an EICR as evidence when regularising uncertified electrical work, but the regularisation certificate itself comes from the council, not from the electrician.
How much does a regularisation certificate cost?
The local authority fee varies by council and is typically a few hundred pounds. On top of that you pay for the EICR from a registered electrician, and for any remedial work the inspection turns up. Because the total depends on the condition of the installation, ask your own council and electrician for figures rather than trusting a national average.
Do I need building regs for the panels themselves or just the wiring?
The notifiable trigger for a normal domestic install is the electrical connection into the consumer unit, not the panels. Rooftop panels are usually permitted development, but the roof must be able to carry the load, so Building Control can still ask you to evidence the structural side if there is any doubt.
What if a previous owner installed the solar and never notified it?
You can still apply for regularisation as the current owner, or, if the issue only surfaced during a sale, deal with it through Building Regulations indemnity insurance. Do not do both in the wrong order: approaching the council usually voids the indemnity policy, so decide which route you want before you contact Building Control.
The next move
Write down the as-built system and dig out any certificate or DNO letter you already have. Book an EICR with a registered electrician so you know whether the installation is safe and what a council would find. Phone your local authority Building Control, which you can find through the GOV.UK council finder, describe the system, and ask about regularisation and their fee. If the grid side was skipped too, check who your network operator is and file the late notification yourself. Keep every document together, because the sale of the house is where all of this gets tested.
Sources
- The Building Regulations 2010, Regulation 18 (regularisation of unauthorised building work).
- GOV.UK, Building regulations approval: how to apply (regularisation from a local authority building control body only, work since 11 November 1985).
- Planning Portal, Regularisation and Failure to comply with the building regulations (section 35 prosecution, unlimited fine or imprisonment, prosecution usually of the person who did the work; section 36 notice up to 10 years after completion).
- GOV.UK, Find your local council (to reach local authority Building Control).
- Energy Networks Association, Find my network operator (identify your DNO for a late G98 or G99 notification).
