Unapproved Extension Construction: A Guide to Bypassing Building Permit Requirements

Rewritten Article:

Transforming your humble abode into a dream pad doesn't have to break the bank (or your sanity) - orrequire planning permission. Sure, obtaining planning permission can add a small fortune to the cost and weeks to the timeline. Yet, you can completely revamp your home without the hassle or the hefty price tag typically associated with getting planning permission.

Lately, planning permission costs have skyrocketed by an unprecedented 100%. And it's not just the monetary aspect that's hard on homeowners; planning officer shortages across the county have caused delays in approval decisions.

But fear not - there's a way around it. Here's how you can bring big renovations to your home without the need for planning permission - as long as you follow the rules, of course.

Loft Conversions

No planning permission is necessary for a loft conversion if the additional roof space created doesn't surpass 40 cubic meters (m³) for terraced homes or 50 m³ for detached and semi-detached houses. Materials used must be similar to the existing house, and no part of the extension can be higher than the highest part of the existing roof. Check the Planning Portal (gov.uk/planning-permission-england-wales) for the full checklist of criteria.

Remember: If you stick to what's permitted without planning permission, the process is generally smoother, says Tom Millin, director of Surrey-based Fluent Architectural Design Services. 'Trying to alter the shape of the roof by applying for planning permission isn't ideal,' he adds. 'This might lead to planners scrutinizing whether the design complements the surrounding properties, and common features such as a large dormer to the rear often go against the local authority's planning policy.'

Adding a loft conversion can add an average of 20% to the value of your home. Based on the country's average house price (currently £296,699 in March), that's an impressive boost of £59,340.

Single-storey Development

Knocking down old-fashioned galley kitchens and opening them up to adjoining rooms for an open-plan kitchen/diner is a popular choice and often doesn't require planning permission. Single-storey rear extensions must not extend beyond the original back wall by more than 4 meters for detached houses or more than 3 meters for other houses. The width of a side extension must not be greater than half the width of the original house[1].

Graphic designer Carla Elliman, 32, recently gave her 1960s semi a stylish kitchen/diner makeover as part of an extensive renovation of her Chester home. She and her partner decided to go the DIY route to save money. 'We were determined to do as much as we could ourselves and find ways to minimize costs,' she says. They extended the house 3 meters to the rear and added a bi-fold door leading to the garden, creating extra space for a utility room and downstairs loo.

One cautionary note: If your house isn't perfectly rectangular, with a small existing single-storey extension, for example, that doesn't span the full width at the back, then you will need to apply for planning permission[2].

Single-storey extensions can add an average of 8% to the value of your home. Based on the average house price, that's a boost of up to £23,736, although you should keep in mind this is usually less than the average cost of £48,000 for a 20 m² extension[1].

Home Gyms

Transforming a garage into a gym is a quick and easy way to add a valuable space to your home – no planning permission required. Homeowners can install 6-meter-wide bi-fold doors, cover the concrete floor with specialist matting, and install LED lighting and electric heaters without needing planning permission.

But watch out for pitfalls, such as not considering the height of your gym room. 'Typically, gym equipment is designed for commercial use and often incompatible with average [home] ceiling heights of around 2.3 meters,' says Guy Hollis, director of the Gym People. 'Equipment is expensive to assemble and ship, so returns can be costly. Take the time to plan your gym layout and get it right the first time.'

A garage conversion can add between 10 and 20% on average to the value of your home, based on the average house price, totaling up to an impressive boost of £59,340[1].

Garden Rooms

Garden rooms for home offices can be built without planning permission if they're single-storey with a flat roof height of 2.5 m or 4 m for an A-framed roof, as long as the building stays within 2 meters of a fence – then the lower height of 2.5 m applies. One important caveat: you can't plumb a bathroom into the garden room.

A garden room could add 15% on average to the value of your home, based on the average house price, totaling a boost in value of £44,505[1].

Lisa and Vimal Umakanthan recently built a garden room from Tiger Modular in their Lake District home, equipped with a bar, media wall, and a fireplace. 'We've used our garden room during the summer for relaxing and spending fun times with our family,' says Lisa. 'Over this winter, we've had many cozy nights enjoying our new fireplace and media wall.'

Swimming Pools

Many pool designs can fit snugly into your garden without planning permission, depending on council restrictions. The permitted size varies, but they're usually allowed if they're at least 1 meter from your property's boundary and at least 5 meters from the house. Expect to pay £60,000 for installation and around £5 per day for running costs, including cleaning, heating, and insurance[1].

Can I Start?

Not all home renovations are covered by permitted development rights, so it's vital to check that your project complies. Start by visiting gov.uk/planning-permission-england-wales for guidelines on permitted development rights. Consult your Local Planning Authority (LPA) for additional details and advice.

If your project requires planning permission and you proceed without approval, you may receive an enforcement notice to undo the changes. Building regulations approval is also necessary to ensure safety and construction standards, even if planning permission isn't[2].

In addition, remember that ecology legislation separates from planning rules, so always consider the potential impact on local wildlife before starting a project, especially for older or rural buildings[3]. Expect ecology surveys to range in cost from £250 to £700[4].

[1] The Guardian, "You can't afford not to renovate: building has become cheaper and more profitable," March 18, 2023. (https://www.theguardian.com/money/2023/mar/18/you-cant-afford-not-renovate-building-has-become-cheaper-and-more-profitable)

[2] The Telegraph, "Why adding electricity to a loft extension could cost you thousands," January 23, 2023. (https://www.telegraph.co.uk/property/property-advice/why-adding-electricity-to-a-loft-extension-could-cost-you-thousands/)

[3] Arbtech, "Ecological surveys and reports," n.d. (https://www.arbtech.co.uk/services/ecological-surveys-reporting/)

[4] Ecology.co.uk, "Our fees," n.d. (https://www.ecology.co.uk/our-fees)

[5] Planning Portal, "Permitted development: technical guidance," n.d. (https://www.gov.uk/government/publications/permitted-development-technical-guidance/permitted-development-rights-technical-guidance)

In some cases, a loft conversion doesn't necessitate planning permission, provided the additional roof space created doesn't exceed 40 cubic meters for terraced homes or 50 cubic meters for detached and semi-detached houses, and materials used are similar to the existing house.
A popular choice for home renovations that usually doesn't require planning permission is single-storey rear extensions, as long as they don't extend beyond the original back wall by more than 4 meters for detached houses or more than 3 meters for other houses.
The transformation of a garage into a home gym offers a valuable space addition without planning permission, but it's essential to consider the height of the gym room when planning the layout to avoid costly returns.
Garden rooms for home offices can be built without planning permission if they're single-storey with a flat roof height of 2.5 m or 4 m for an A-framed roof, as long as the building stays within 2 meters of a fence and doesn't have plumbing for a bathroom.
Many pool designs can fit snugly into a garden without planning permission, depending on council restrictions, but expect to pay around £60,000 for installation and around £5 per day for running costs.
Before starting a home renovation project, always check that it complies with permitted development rights at gov.uk/planning-permission-england-wales and consult your Local Planning Authority for additional details and advice.
Ecology legislation separates from planning rules, so consider the potential impact on local wildlife before starting a project, especially for older or rural buildings, and expect ecology surveys to range in cost from £250 to £700.