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Converting A House Into Two Flats: Costs And Planning Guide

11 August 2019
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Eugene Kim

Converting A House Into 2 Flats

More and more homeowners are converting their homes into flats. And it is quite apparent why – the ever-growing demand for flats in London. More homeowners now realise that splitting their property into units helps them increase rental income and increase property value. So how do you convert your house into flats and what are the expected costs? The following guide should help you in this regard.

Planning Guide

If a house has to be divided into multiple units, it will be required to obtain planning permission. 

  • If it is a listed building, you may need listed building consent. Make sure to contact the local planning authority before starting work. 
  • If the building is in a conservation area and the conversion involves demolition, it will be required to apply for planning permission for relevant demolition.

Building or Flats Regulations

When a property is converted, it is required to get approval under the Building Regulations. It is required under the Housing Act 2004 for sub-divided buildings to meet standards. Houses that involve multiple occupation should also be licensed. Fire escape concerns will also need to be addressed, requiring you to consult the Fire Service.

Convert House into 2 Flats Cost

The cost of converting a house into flats depends on the property. The factors influencing the costs include the following:

  • New house design
  • Size of the property
  • Condition of the house
  • Number of flats to be converted to

A standard conversion should cost around £25,000. It can involve installing central heating, walls, and bathrooms. When it comes to budgeting for the conversion, it will be required to take many factors into account. This includes:

  • Planning approval from your local planning authority
  • Approval for building regulation
  • Finance for development
  • Installation of new utility meters (electricity, water, and gas)
  • New heating systems and boilers
  • New bathroom and kitchen
  • Sound deadening/tests
  • Building second entrance

If the existing building is sound and the existing bathroom and kitchen can be used, you should expect the cost of conversion to be in the range of £15000 to £25000. The cost of decoration can be additional.

Such a conversion project can be considered to be a major and complex development project. Whilst its scale can vary, you should expect it to take up to 6 months to be completed. 

Market research

If you are thinking of converting your home into flats, make sure that you have conducted a market research to determine the demand for flats in your area. The part of the property that you will be converting should also be well planned. 

Get professional help

When it comes to applying for planning permission, it is best to seek professional guidance. A reputable service can help you with your planning strategy. They already have experience with the processes and know what the planners are looking for – from qualitative principles to the minimum space standards for conversions. The from the surrounding areas, neighbours, and amenities, everything can be addressed to ensure that your project gets approval.

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Eugene Kim

Eugene Kim, Founder and Managing Director of Extension Architecture, has led the firm for over 14 years, consistently delivering quality solutions. His dedication has been key to the company's growth and success.

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