Buying a loft conversion with no building regs?
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A loft with dormer windows post conversion. SAM Conveyancing discuss the importance of Building Regs for Loft Conversion and what you can do if you're buying a house without building control sign off.

Building Regs for Loft Conversion

(Last Updated: 18/06/2024)
21 min read
Key Takeaways
Buying a house without building regulations for a loft conversion is a major issue.
  • The loft conversion may not be legally habitable.
  • The property may not be worth the full asking price.
  • Indemnity insurance exists to protect against the risk of repercussions from the Local Authority.
  • You cannot use indemnity insurance if the local authority is already aware that the loft conversion is non-compliant.
  • You may still be able to buy the property with certain conditions, but it's important to understand the risks.
  • Building Control authorities cannot grant letters of regularisation for loft conversions - and other works - finalised before 11 November 1985, when the Building Act came into force.

Can a loft be used as a bedroom?

Sellers often create a new bedroom in the attic, to turn unused space into living space and add value to the property without changing the house's footprint. Loft conversions can increase house prices by as much as 20%. This makes them particularly appealing in areas where planning permission for an extension may be difficult to obtain or in a crowded area where there simply isn't space between existing buildings to create another room.

However, much like a garage conversionthe seller and their estate agents should not market a loft conversion without building regulations as a bedroom if it does not have a building regulations completion certificate.

Skip ahead to read the regulations required to sign off a loft conversion.

Do you need a loft conversion survey?

Our RICS Surveyors will inspect the loft as part of a Level 2 or Level 3 Home Survey. We have a nationwide panel of experienced local RICS surveyors who can help check the quality of your loft conversion.

If your surveyor has already identified a suspected regulatory breach, our independent structural engineers can assess the converted loft and outline the remedial works required without notifying the local authority.

Why are non-compliant loft conversions a problem?

Building regs exist to ensure our homes are safe. If work is non-compliant, there is a reasonable chance that the loft room, or even the whole building, is dangerous and at risk of collapse. Even if you are confident the non-compliant works do not pose a safety risk, if they were completed less than a year ago, the local authority may force you to remedy the building work, often at great expense.

Lenders will not grant an offer without a valid indemnity policy against the risk of action from the Local Authority, and they will revalue the house based on the actual number of legally habitable rooms. If the work is not remedied to make the loft a legally habitable room, these issues will resurface whenever you come to sell or mortgage the property.

You cannot put tenants in a loft room which isn't legally habitable. You may face legal repercussions, especially if they suffer any injury due to the breach. Having a loft conversion without building regs sign-off may also invalidate any building insurance, so you wont be covered if the new loft collapses.

What are my options if I still want to buy the house?

Understandably, many buyers will pull out at this point and find another house which is less hassle. However; if you are attached to this one, you do have some options.

Option 1: Indemnity Insurance & Negotiation

If you can get insurance and your seller will adjust the price to meet the lender's valuation, you may choose to proceed with the purchase. This is the simplest and cheapest option, but you may still be moving into an unsafe home.

Option 2: Indemnity Insurance & Cash

If you can get insurance and your seller will not adjust the price, you may choose to buy the house anyway by making up the shortfall in the mortgage offer with your own cash. This is a risky option as you may find you'll have lost money by paying above the property value, and you'll still have the added cost to re-do the works to make it a safe and legally habitable space.

Option 3: Structural Engineer & Surveyor

With the seller's consent, our expert structural engineer can carry out an intrusive survey to identify whether the works are compliant with 'Part A: Structure' and advise on remediation costs, if required. You will still need your RICS surveyor or an architect to inspect the other aspects of compliance, such as insulation, fire safety, and stair dimensions; if your RICS surveyor is required to conduct an intrusive inspection of these elements, this may increase their fee. You will need written consent from the seller.

They will not notify the local authority, so if the works are not compliant, you could still get insurance for the purchase. However, your solicitor will be obligated to inform the lender, who may withdraw or adjust their offer.

If the works are compliant, you will still need to instruct the local authority to send their own inspector to confirm this and issue a letter of regularisation.

Sellers prefer this option because if you choose to pull out of the purchase, they can find another buyer, and the local authority will not be made aware of the breach.

Option 4: Letter of Regularisation

With the seller's consent, you can skip the structural engineer and have the local authority's inspector assess the converted loft. If the works are noncompliant, an indemnity policy will not be a viable option, so you will not be able to purchase with a mortgage until the noncompliant works are remedied and a letter of regularisation can be granted, so the lender is satisfied that the building is safe and structurally sound.

Sellers are less likely to consent to this option, as they risk being unable to sell to you or to any other mortgage buyers until the problem is fixed, and they and their builder may face consequences for the illegal work.

NB: Any intrusive works are remedied at the seller's own expense, so they may be reluctant to consent to option 3 or 4. However, they will face the same issue selling to any other buyer who is doing their due diligence, so stand your ground and don't be pressured into taking unnecessary risks.

Do you need planning permission for a loft conversion?

Most loft conversions don't require planning permission because they fall under permitted developments, so buying a house with a loft conversion without planning permission isn't normally an issue.

Loft conversions do require planning permission if:

  • Your space addition is going to be equal to or greater than 50m³ (40m³ for a terraced home); or
  • You live in a listed building or conservation area; or
  • You are going to alter the roof height or shape

For more information, visit the Government's Planning Portal.

Can you sell a bedroom loft conversion which doesn't have the correct building control sign-off?

Yes, you can, although the issue may make your sale difficult, particularly if the buyer is using a mortgage.

You cannot describe a loft conversion that hasn't been properly signed-off as a bedroom; technically, this is a misrepresentation, which has serious repercussions. If you attempt to hide it, even if the estate agent describes the conversion as such and the mortgage valuation misses the issue, the buyers solicitor will likely find out during legal enquiries.

The mortgage lender will offer less, and may require the buyer to fork out for a structural engineer to assess the safety of the new room. Be honest with your buyers. If you are not willing to remedy the issue before sale, you may find the best solution is to sell to a cash buyer at a fairly adjusted price.

How do you find out that building control certification for a loft conversion is lacking?

You, your mortgage valuer, or your RICS home surveyor may notice visible breaches of the regulations; or, your conveyancing solicitor may find the necessary certificate is missing from the local authority search carried out during the legal enquiries stage, before they produce the final report on title.

Don't rely on the Mortgage Valuation Survey flagging up unauthorised building works

A standard inspection report assumes that everything is above board and leaves the solicitor to find out otherwise:

"5. In carrying out the inspection it has been assumed: (...)

e) That all Planning and Building Regulations and other consents have been obtained and complied with.

Additionally, within the 'Property Description' section, the reference to bedrooms merely presents a box for the numbered to be filled in:

Number of bedrooms: x

Advantages of getting a Letter of Regularisation

You get the 'gold standard' - your conversion gets the legal stamp of approval and can be designated property (e.g. you can describe the loft conversion as a bedroom loft conversion when you come to sell up). You can also rest assured that your conversion meets fire safety standards and is efficient from a thermal perspective.

Disadvantages of getting a Letter of Regularisation

The process is long and expensive, it can seriously disrupt or collapse a sale. If the works are non-compliant, they will not issue the letter of regularisation unless remedial works are completed. The Local Authority will be aware of the issue and you won't be able to get insurance, which means no mortgage.

For this reason, we recommend an inspection by a structural engineer to find out whether it meets regulations and, if not, how much work will be involved in fixing the problem.

Should I get building regulations indemnity insurance?

Insurance can cover both the buyer and lender against any financial losses should enforcement action be taken against them (or future owners of the property), it covers the market value of the property.

The seller usually pays the insurance premium of around £180 and £500, but it must initially be paid by the buyer and then reimbursed. It would not be the seller's interests to refuse this relatively small cost and delay the transaction.

Lenders will most likely insist that the buyer takes out this insurance to protect themselves in the event the local building authority carries out enforcement action (either by a Section 36 Notice or an injunction) and the building subsequently suffers from a loss in value because for example, the conversion has to be returned to the original loft space by order of a court.

Things to consider:

  • Most importantly, the insurance does not cover you against the loft conversion collapsing.
  • The insurance essentially protects you against local building authority enforcement action costs. However, the local building authority only has one year after the works have been put up to serve an enforcement Section 36 Notice (or four years for a new-build property)—yet it's a normal condition of this insurance that you can only get it after a year has elapsed (four years if the property is new-built).
  • The insurance may cover the homeowner against the local building authority taking out an injunction - which they may do at any time after the works have been constructed (there's no time limit), particularly if they believe a structure is unsafe. Read all the details of the insurance policy carefully.
  • The insurance may only be granted on the condition that a survey be carried out, typically by a Structural Engineer or an RICS surveyor. If either of these professionals provides evidence that the work is unsafe, then the insurance will not be granted.
  • You will not be insured if you've contacted the local building authority about retrospective building control sign-off for the unauthorised loft conversion.
  • You can't get this insurance if the local building control authority has already refused the offending works.
  • You can only get this insurance if the dwelling has been a residential home for at the previous year, at least.
  • Secrecy about these policies is a major feature. You cannot normally tell any third party that you have taken out the insurance; if you do, the insurance is invalidated.
  • You need consent from the insurer if you plan to do any further building works; this is because if you have to go through building control and have your works inspected, the local building authority may find out about the unauthorised loft conversion and then choose to act. Consent might not be given.

Advantages of getting Building Regulations Indemnity Insurance for an Unauthorised Loft Bedroom Conversion

If you can get it, it's normally going to be far cheaper than any other remedy. Most importantly, it's far quicker to obtain and so less likely to hold up a sale. This means negotiations between buyer and seller regarding who foots the bill are likely to be cordial, facilitating a purchase where it may not otherwise be possible. The insurance will still be valid for your buyers if and when you come to sell the property on.

Your conveyancing solicitor will provide legal advice on the indemnity insurance policy to ensure you understand the risks and implications.

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Disadvantages of getting Building Regulations Indemnity Insurance for an Unauthorised Loft Bedroom Conversion

As a buyer, you're not insured against the worst disaster of the conversion collapsing. Additionally, up to press time, no local authority has yet been granted an injunction to alter or take down a loft conversion, so given that you can't get cover for the initial 12 months, when a Section 36 Notice can be served, it's unlikely that you'll ever have a call on the cover.

Finally, taking out this insurance simply 'kicks the can down the road': when you come to sell, you still have the problem of an unauthorised loft conversion, which will come up with any potential buyers.

Worried about whether a bedroom loft conversion isn't building regulations compliant?

You should instruct experienced conveyancing solicitors from the outset who can discover this issue at enquiries stage. You are also well advised to book a RICS house survey because your RICS surveyor can raise suspicions if they think an installation isn't building regulations compliant. If this is the case, you may choose to pull out before it's too late, or instruct one of our structural engineers to carry out an intrusive inspection.

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Frequently Asked Questions
Andrew Boast of Sam Conveyancing
Written by:
Andrew started his career in 2000 working within conveyancing solicitor firms and grew hands-on knowledge of a wide variety of conveyancing challenges and solutions. After helping in excess of 50,000 clients in his career, he uses all this experience within his article writing for SAM, mainstream media and his self published book How to Buy a House Without Killing Anyone.
Caragh Bailey, Digital Marketing Manager
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Caragh is an excellent writer in her own right as well as an accomplished copy editor for both fiction and non-fiction books, news articles and editorials. She has written extensively for SAM for a variety of conveyancing, survey and mortgage related articles.

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