May 1, 2024

How to Value a Loft Conversion

If you own the house or are the freeholder of your building, this guide is not for you. But if you’re a leaseholder with...

If you own the house or are the freeholder of your building, this guide is not for you. But if you’re a leaseholder with a loft space above your flat and are considering a conversion, read on.

Most likely, you do not own the loft space. Check your lease. It may prohibit alterations even if you own the loft. External parts typically owned by the freeholder can pose challenges too. Freeholders can charge a fee for granting permission to carry out works or even prevent it.


You’ll need to get:

  • comparable sales evidence of before and after loft conversions
  • detailed build costs obtained from quotes provided by contractors
  • a breakdown of professional fees

Note: a deduction will be applied to reflect the risks borne by the leaseholder during the build. Leaseholders usually bear all build risks, warranting a further deduction. 

Also note that party wall agreements and licences to alter should be considered too.

A chartered surveyor’s report goes into more detail in respect of these aspects but knowing them is important for any leaseholder contemplating a loft conversion so that they can argue their case with their valuer - but you will still need to engage an RICS Registered Valuer to make a formal valuation.


Once plans for construction work are being made, people immediately start thinking about how they’ll navigate planning permission requirements.

Planning permission often stands as a “big ticket” item in most construction projects because it determines what’s allowed and what isn’t. So where does it fit into our timeline?


Starting out on any project involves establishing basic principles of an envisioned scheme through design before subjecting it to viability assessments when progressing into more detailed planning.

Think planning requirements, structure, cost, build-ability and programme of works which all play key roles in decision-making before finalising a project.


Checking the planning viability of a project in its early stages might involve looking at permissions granted on similar projects in the area or consulting local authority planning guidance notes. Some building work on domestic properties falls under “Permitted Development” which means that you wouldn't need to apply for planning permission. The Government's Planning Portal holds detailed rules on Permitted Development.


Where planning permission is required, the next step will typically be “Pre-Application Advice” from the local planning authority (LPA). Local planning departments recommend this stage as it establishes a constructive dialogue between the applicant and the authority without risking failure of a full planning application submission.

The pre-application stage also allows the applicant to be informed of potential planning issues and identifies the planning policies that will guide the scheme during the time when you will actually seek planning approval. To request Pre-App Advice, an applicant must submit information about their scheme to the LPA and pay a fee. All relevant information needed for planners to provide detailed comments should be provided by your design team as part of your Pre-App submission. A comprehensive submission enhances the LPA’s ability to offer such insight. The LPA will then give written feedback and hold a meeting if necessary.

If you haven’t got the time to go through a pre-application process, then you may want to just plough straight on with full planning knowing that discussion will take place and design adjustments can be made via this route anyway.

The trade-off is that if planning permission is ultimately refused the prospects of being successful in another full planning application for the same project are diminished. This is why developers like to have an “off the record” decision in respect of whether their scheme is likely to get approval or not by way of pre-application.

Your own design team reviews and adjusts upon receiving feedback from LPA findings. Any changes made must then undergo scrutiny based on other viability considerations before finalising. Upon finalisation, you'll proceed to submit the full planning application, aiming to get planning permission for the development. Remember that it doesn't end there: most notices come with conditions that must be carefully reviewed and adhered to before, during and after construction.

Planning requirements

Planning requirements matter in everything related to design and construction. Though Permitted Development rules are generally straightforward it’s still advisable to apply for a Certificate of Lawful Use from your local planning authority so as to have confirmation that your proposed or completed work does fall within the Permitted Development category. During property sales when buyer solicitors seek confirmation of the property's planning status, this Certificate of Lawful Use will prove beneficial.