How to unlock up to 1.6 million homes through Permitted Development rights

The government aims to deliver 1.5 million homes during this parliamentary term, with a potential target of 370,000 homes annually—a total of 1.85 million over five years. A shortage of existing planning permissions threatens to delay progress, especially early in the term. One practical solution is expanding Permitted Development Rights (PDR), allowing detached homes to be converted into semi-detached units without full planning permission. This policy offers an efficient way to meet housing demand while supporting sustainability, affordability, and gentle urban densification.

A Scalable, Practical Solution

By extending PDR, detached homes meeting specific criteria could be swiftly converted, reducing the delays often caused by traditional planning processes. This aligns with initiatives like Street Votes, which promote moderate densification and has gained support from groups traditionally in opposition to each other. PDR already allows for certain extensions and conversions with little opposition. Expanding it to include detached home conversions offers a scalable, adaptable solution to the housing shortage, particularly in high-demand urban areas. It is also preferable to the conversion of barns or office spaces, which are often located in isolated or less suitable areas.

Ensuring Quality Through Clear Criteria

The Room to Grow policy would apply strict criteria to ensure quality:

  • Location: Homes must not be in Conservation Areas, Areas of Outstanding Natural Beauty (AONBs), or open countryside.

  • Space: Each unit must provide 58 sqm of internal space, meeting national standards for a 2 storey home. Existing PDR rights for extensions can be utilised. Plots would need to be at least 8 metres wide at the point of the principal elevation to ensure adequate space for two homes to be created side by side.

  • Design: Only minor external changes to principal elevations, such as new porches, would be permitted to maintain neighborhood aesthetics.

  • Garden & Parking: Each unit must have at least 50 sqm of garden space, with more for larger homes, and parking provisions based on proximity to public transport.

  • Energy Efficiency: Converted homes must meet high energy efficiency standards, including low-energy heating systems and solar panels where practical.

These criteria ensure that conversions enhance the quality of life for residents and integrate seamlessly into existing communities. The conversion process would allow all primary living spaces to remain on the ground floor which effectively eliminates any concerns in relation to neighbouring amenity. The policy could begin delivering homes within the first year of implementation.

Potential Impact: 1.6 Million Eligible Homes

Of the 4.8 million detached homes in the UK, 1.6 million could be eligible for conversion under this policy. If 20% of these homes are converted, it would create 320,000 new homes—equivalent to around one year’s housing need. While not all eligible homes will be converted, there could be an initial surge when the scheme is introduced. Even with this intervention, the supply of detached homes would remain robust, as only 1 in 3 is expected to meet the criteria.

Cost-Effective Conversions

Residential conversions are a cost-effective option and often only require internal modifications and minor external changes, making this a swift and affordable solution to the housing shortage. For homeowners, this policy offers financial benefits: they can release equity, generate rental income, or sell part of their property to clear debts or help the next generation purchase a home. This is especially advantageous for those who are asset-rich but cash-poor, allowing people to create homes that suit their changing needs while remaining in their communities and reducing ongoing costs. Notably, there are around 25 million empty bedrooms in Britain currently. 

Economic Benefits for Local Communities

Expanding PDR benefits local economies by creating opportunities for small builders and contractors, who are often focused on extensions but could shift to new home conversions. It also increases demand for architects, designers, and planners as homeowners explore conversion options. This decentralises wealth from large developers, ensuring more economic gains flow into local communities.

Diversifying Housing Supply

This policy diversifies housing options by focusing on converting detached homes into smaller, affordable units in established neighborhoods. Unlike large greenfield developments, it offers housing that meets the needs of those who prefer urban living.

Promoting Economic Equity

Converting detached homes into semi-detached units in high-demand areas makes housing more affordable, making homeownership more accessible and addressing housing inequality. This promotes economic equity across different demographics, ensuring housing is available to first-time buyers and young families.

A Politically Savvy Solution

This policy provides a clear path to meeting housing targets early in this parliamentary term. It reduces the burden on Local Planning Authorities, which often face resource constraints. Expanding PDR is a progressive, forward-thinking solution that delivers homes quickly, supports SMEs, and ensures the UK’s housing stock is fit for the future.

By offering a practical, cost-effective, and scalable solution, this policy, or a variation of it, will help tackle the housing crisis while promoting economic equity and sustainability— surely key priorities for our housing strategy.