Knowledge Base
Planning, regulations and construction, explained.
Topic 09
Garden rooms, porches, driveways and other small works
Permissions and practical considerations for garden rooms, porches, driveways and other smaller home improvements.
13 articles
Outbuildings and annexes
01Garden rooms, offices and gyms: size, height and boundary limitsA garden room, home office or gym can often be built without a planning application if it is incidental to the house and meets every permitted-development limit. Its use, position, overall height and the amount of garden already built over matter as much as its floor area.02Can someone sleep or live in an outbuilding? Ancillary use explainedA new outbuilding intended as a bedroom or living annexe cannot normally rely on the incidental-outbuilding permitted-development right. Using an existing lawful building as accommodation within the same household is a different question from creating an independent home, and must be assessed on its facts.03Granny annexes: planning, building regulations and CILA newly built detached granny annexe normally needs planning permission and building regulations approval. CIL may apply even to a small new dwelling, but a qualifying residential-annexe exemption can be claimed before work starts; it is separate from biodiversity net gain exemptions.04Building regulations for outbuildingsSome small detached outbuildings without sleeping accommodation are exempt from most building regulations. The main tests concern floor area, whether the building is detached, storeys, distance from the boundary and construction materials; electrical and certain water-supply requirements can still apply.
Front of the house
05Porches: when they need planning permissionA porch outside an external door of a house can be permitted development if its external ground area is no more than 3m², its height is no more than 3m, and no part is within 2m of a boundary with a highway. Those planning limits are separate from the building-regulations exemption.06Front driveways and permeable pavingA new or replacement front driveway can often avoid a planning application if it is permeable or drains naturally to a permeable area within the property. More than 5m² of impermeable surfacing without that drainage arrangement normally needs planning permission, and vehicle access needs a separate check.07Dropped kerbs: getting council approvalObtain approval from the highway authority before creating or widening a dropped kerb across a public footway. Planning permission may also be needed; in Epping Forest District, Essex County Council deals with the highway crossing while the district council handles the planning question.08Fences, walls and gates: height limitsA new fence, wall or gate can normally be permitted development up to 1m high beside a highway used by vehicles, or up to 2m elsewhere. Listed-building connections, withdrawn permitted-development rights and the difference between replacement and demolition can change the answer.09Bin and bike storesA permanent bin or bike store in front of a house normally needs planning permission because the ordinary outbuilding right excludes that position. Some small movable storage is not development, while a rear-garden store may qualify for permitted development if every relevant condition is met.
Energy upgrades
10Air source heat pumps: the permitted development rules (changed May 2025)An air source heat pump can be permitted development if it meets the equipment, location and noise conditions. Changes from 29 May 2025 removed the general 1m boundary setback and widened some allowances, but they did not remove the need for a site-specific compliance check.11Solar panels: permitted development, conservation areas and listed buildingsSolar panels can often be installed without a full planning application, including on some properties in conservation areas, but the location and property type are decisive. Rules changed on 27 August 2026, and listed buildings, particular protected locations and some installations requiring prior approval need separate checks.12EV chargers at homeA home EV charger serving lawful off-street parking can often be installed as permitted development, subject to equipment limits and site restrictions. Charging across a public pavement is a separate issue, with new planning provisions confirmed to take effect on 21 October 2026.13Air conditioning units: planning and building regulationsAir conditioning is not banned in homes, but a fixed installation can need planning permission and building-regulations approval. A cooling-only unit cannot rely on the domestic air source heat-pump permitted-development right, while a qualifying reversible heating-and-cooling system may do so.