With UK house prices at historically high levels, you may be considering making home improvements instead of moving house. This can make great financial sense when you compare the relative costs, but before you start knocking down walls or extending your living space you need to know what requires planning permission and what doesn’t.

When do I need Planning Permission?

Building something new, or making major changes to your home will often involve planning permission. Check our handy guidelines for the most common home improvement projects.

Planning Permission for Conservatories

Adding a conservatory to your home is considered a “permitted development” and does not normally require planning permission providing that it complies with the following conditions:

  • It doesn’t cover more than half your garden
  • It doesn’t extend beyond the rear wall of the property by more than 4 meters for detached houses or 3 meters for other properties. In 2013 the Government temporarily doubled the sizes quoted above so that until May 2019 you can extend up to 8 metres beyond the rear wall for detached properties and 6 meters for other house types as long as you participate in a Neighbour Consultation Scheme
  • The height does not exceed 4 meters (or 3 meters if within 2 meters of your boundary)
  • The roof tip is no higher than the eaves of your property

Even if you do not require planning permission your conservatory may still be subject to building regulations which is a separate matter. Building regulations are national standards which apply to most building types to ensure that our dwellings are safe.  Your conservatory will be exempt if:

  • It is built at ground level
  • Has a floor area less than 30 meters square
  • Has an independent heating system
  • Is separated from the original house by an external wall or external windows and doors.
  • Is at least 1 meter from the property boundary.

Most reputable conservatory companies will take care of planning permission and building regulations on your behalf.

Planning Permission for Loft Conversions

Planning permission is not normally required for loft conversions except where you extend or alter the existing roof space. In addition, as long as the volume of the loft conversion does not exceed 50 cubic meters (40 for terraced properties) and does not have any verandas, balconies or raised platforms it will be considered a “permitted development”.  Please note that different rules apply to loft conversions within flats.

As with conservatories, a loft conversion will still need to satisfy building regulations to ensure that it is structurally sound. You will require building regulations if:

  • You are planning structural changes to your property or removing or rebuilding a major part of a wall
  • You are converting that area into a living space with a permanent staircase, windows and electricity
  • You are re-roofing and using a different material
  • You are replacing windows or external doors
  • You are using cavity wall insulation

Planning Permission for Doors and Windows

You would not require planning permission when repairing or replacing windows and doors providing they are of similar appearance to those used in the construction of the property. If you are planning substantial changes, for example a new bay window or skylights, these may be subject to approval dependant on their specification.

Building regulations have applied to all replacement glazing since 1st April 2002.  If, however, you use an installer registered with the relevant “competent person” scheme such as FENSA, your registered installer can carry out the work to comply with building regulations but without involving local authority building control.

Planning Permission for Decking

Garden decking is exempt from planning permission and building regulations provided that the decked area is no more than 30cm above ground level and does not cover more than 50% of the original garden area. It is important to note that when calculating whether your project will cover more that 50% of the garden area you must include any other outbuildings and extensions that have been added to the property since its construction.

Planning Permission for Kitchens & Bathrooms

Installing a new kitchen or bathroom does not generally require planning permission unless it is part of a house extension. Any major renovation works that may include plumbing and/or electrical alterations will be subject to building regulations and therefore should be carried out by an appropriately qualified tradesman.

What happens if you carry out works without planning permission?

Whilst it is not a criminal offence to commence works without the appropriate consent it is considered unlawful and your local authority can take action to have the work brought up to the required standard at your own personal expense or even enforce demolition. Retrospective planning applications can be made but this is risky and can be very costly.

If no enforcement action is taken within 4 years of the project completion, a legal loophole renders the development lawful but this too is at your own risk. Please note that a change of use (other than change of use to a single dwelling) requires 10 years to pass before becoming immune from enforcement.

Listed buildings are an important exception to these general rules. Altering a listed property without prior consent is considered a criminal offence which can result in a hefty fine and, in extreme cases, prosecution and imprisonment.  We would of course always recommend doing your homework and obtaining the appropriate consent in advance.

With regard to building regulations, you don’t always need to get the approval yourself if you are using an installer registered with the relevant competent person scheme but you must ensure that the regulations are being met.

Getting further help and advice about applying for planning permission

If you are unsure whether your home improvement projects require planning permission or building regulations consent we would strongly suggest that you speak to your local authority planning and building control department. Our expert conveyancing team can also provide you with guidance and assist with any other property related matters.  Contact us today for a free initial consultation at a time convenient for you.


The Backhouse Solicitors Property Team

Tel:         01245 893400

Email:    info@backhouse-solicitors.co.uk

Web:     www.backhouse-solicitors.co.uk