The planning rulebook was rewritten this month, which has produced a fresh crop of confident claims about what you can and cannot build in your garden. Most of them are wrong. Here is what actually changed, plus two other developments worth knowing before you sign a garden room contract.
A new National Planning Policy Framework, and why it does not change your garden room
The government published a new National Planning Policy Framework on 17 August 2026, and its policies count in planning decisions from that date. The headline measures are a default “yes” for housing within reasonable walking distance of well-connected railway, tram and Underground stations, and stronger protection for pubs, where a developer must show there is “no reasonable prospect of a pub remaining viable” before converting one.
Neither touches garden buildings. Permitted development rights for outbuildings do not live in the NPPF at all: they sit in separate permitted development regulations, and those were not amended on 17 August. The limits that decide most garden room projects are unchanged. The building must be single storey, no more than 2.5m high if it sits within 2m of a boundary, not forward of the principal elevation of the house, and together with other outbuildings it must not cover more than half the land around the original house.
The practical point: if a supplier tells you the rules have “just changed” and you should order now, that is a sales line, not planning law. Check your own plot against the permitted development limits, and remember that conservation areas, listed buildings and some new-build estates carry extra restrictions that no national announcement removes.
Sources: National Planning Policy Framework, GOV.UK, MHCLG in the Media and Planning Portal, outbuildings.
3,841 construction firms failed in a year, which is a deposit problem
The Insolvency Service published its July figures on 18 August 2026. Construction recorded 343 company insolvencies in the month, up around 3% on June’s 332. Over the 12 months to July 2026 the industry lost 3,841 companies, 17% of all cases where an industry was recorded and more than any other sector.
Garden room suppliers sit inside that statistic, and the business model makes it sharper than usual: most take a substantial deposit months before anything is delivered. If the company fails in the gap, an unsecured deposit is usually gone.
How to protect yourself: pay the deposit by credit card where you can, because Section 75 of the Consumer Credit Act makes the card provider jointly liable for purchases over £100 and up to £30,000. Look the company up on Companies House and read the filing history, not just the reviews. Push for staged payments tied to delivery and installation rather than a large sum up front, and be wary of a discount offered specifically for paying more in advance.
Source: Insolvency Service commentary, July 2026.
Coming in October: the old wiring regulations are withdrawn
This one is not new this month, but the deadline is close enough to matter for anything being wired this autumn. The IET and BSI published Amendment 4 to BS 7671, the wiring regulations, on 15 April 2026. The previous version, BS 7671:2018+A2:2022+A3:2024, is withdrawn six months later, in October 2026, after a window in which both were valid.
Amendment 4 adds a new chapter on stationary secondary batteries, covering system design, bidirectional inverters, siting, ventilation and fire precautions, revises the rules for Power over Ethernet in section 716, and substantially rewrites the requirements for medical locations.
Why it matters for a garden room: the supply to a garden building is a new circuit, and it should be designed, tested and certified against BS 7671. If your installation is being certified this autumn, ask which version of the standard the electrician is working to and make sure the certificate you are handed matches. If you are also planning battery storage in or near the building, the new battery chapter is the part that applies to you.
Source: IET and BSI, Amendment 4 (2026) to BS 7671:2018.