Amenity space standards and useable outdoor space

Private amenity space standards for flats are set locally, and they almost always have two parts: a minimum area per dwelling, and a requirement that the space be useable. The area is easy to show on a drawing. Usability is where schemes get refused, and the single dimension that decides it is balcony depth. A 5m² balcony at 1.2m deep and 4.2m wide meets an area standard and will not take a table and two chairs. The same 5m² at 1.8m by 2.8m will.

Policy wording varies between authorities, so the first task on any scheme is to read the adopted standard rather than the one you remember.

What local standards usually require

Typical adopted standards set a minimum private outdoor area per flat, stepped by bedroom count or occupancy, with a separate communal requirement where private provision falls short. The London Plan sets a minimum of 5m² of private outdoor space for one and two person dwellings and an extra 1m² for each additional occupant, with a minimum depth and width of 1.5m.

Outside London, standards sit in the adopted local plan or a design supplementary planning document, and they differ considerably. Some are expressed per dwelling, some per bedroom, some as a percentage of the site area for communal space. Some require ground-floor flats to have a defensible private garden rather than a terrace.

Three questions answer most of the policy work: what is the minimum area per unit, what minimum dimension applies, and is communal space acceptable as a substitute or only as an addition.

Houses are usually treated separately, with a garden depth or area standard, and the nationally described space standard deals with internal area only, not external.

Balcony depth and whether it is useable

The furniture test is the one that matters. A table 800mm square with chairs pulled out needs roughly 2m of clear depth. A bistro table with two chairs needs around 1.5m. Below 1.5m a balcony becomes a place to stand, a drying space and a planter ledge, which some residents value and most policies do not count as amenity space.

Deduct the obstructions before calculating area. An inward-opening door sweep, a structural column, a heat pump condenser unit, a riser cupboard and a required maintenance zone all take space out of the useable area, and a drawing that ignores them overstates the provision.

Projecting balconies bring thermal bridging and overshadowing of the flat below. Inset balconies avoid the bridging and lose daylight to the room behind, which can be the difference between passing and failing a daylight target. Semi-inset is the usual compromise.

Winter gardens, meaning enclosed balconies with openable glazing, are accepted as amenity space by some authorities and not by others. Where they are used to deal with noise or wind exposure, the justification should be explicit and the openable area stated, because a sealed winter garden is an internal room.

Communal space against private space

Communal space works where it is overlooked, accessible to every resident, usable for more than circulation, and maintained. It does not work where it is a strip of mown grass between a car park and a boundary fence.

Where policy allows communal provision to make up a private shortfall, the usual conditions are that the communal space is at least a stated area, that it is directly accessible from the common parts rather than through a private unit, and that it receives a minimum amount of sun.

Roof terraces count as communal space in most policies, with the usual caveats about access, balustrade height, wind exposure and overlooking of neighbours. Lift access to a roof terrace is a practical requirement where any resident may need it, and retrofitting a lift overrun is expensive.

Maintenance has to be funded. A service charge mechanism and a management company should be identified at application stage, because an officer who cannot see who will cut the grass will condition a management plan anyway.

Overshadowing of the space provided

Area and depth mean little if the space never sees the sun. The BRE guide's test for amenity areas is the proportion of the space receiving at least two hours of direct sunlight on 21 March, and the reference value is half the area.

Apply it to private balconies as well as to communal gardens. A north-facing balcony on a deep courtyard elevation will fail, and in a dense scheme some units will inevitably be north-facing, so the honest approach is to report the result, say which units fall short, and show the compensating communal provision rather than leaving the officer to find it.

An Overshadowing Study covering the communal and private spaces, with a sun-on-ground plot at the equinox, is the usual evidence. Where neighbouring gardens are affected, that work belongs in the Daylight and Sunlight Assessment instead.

Child play space alongside amenity space

Play space is a separate requirement and should not be double counted with amenity space. London policy uses a child yield calculation per unit mix and requires 10m² of play space per child, with doorstep play for under-fives within the development.

Outside London, many authorities apply a threshold above which on-site play provision or a commuted sum is expected, often set in the local plan or a developer contributions document. The calculation basis differs, so check whether it runs on unit numbers, bedroom counts or population yield.

A Play Space Assessment sets out the yield calculation and the proposed provision by age group. Doorstep play for the youngest age group has to be visible from the dwellings, which constrains where it can go.

Roof terraces and their planning issues

Three issues come up repeatedly. Overlooking of neighbouring gardens and windows from a raised terrace, which is answered with set-backs, screens and planters rather than with a condition. Wind, which on anything tall enough to need a wind assessment can make a terrace unusable for much of the year. And noise, where a terrace above or beside bedrooms generates complaints that lead to hours restrictions.

Design the terrace with a 1.5m to 2m planted buffer inside the parapet where overlooking is an issue, and show the sightline sections. A Wind Microclimate Assessment is normally expected on taller buildings, and the terrace should be tested against the comfort criteria for sitting rather than walking.

Evidencing compliance on the drawings

1. Produce an amenity space schedule listing every dwelling, its occupancy, the required area, the provided private area net of obstructions, the minimum dimension and the communal area allocated.
2. Show the useable area hatched on each floor plan, with the door swing and any plant drawn.
3. Dimension the critical depth on at least one balcony of each type.
4. Include a sun-on-ground plot for 21 March for communal spaces and a note of which private spaces fail the two hour test.
5. Reference the adopted policy by number and state the standard being applied.
6. Set out the play space yield calculation separately.

That schedule is what the case officer will use, and producing it yourself prevents them producing a worse one. A Design and Access Statement should carry the design reasoning behind the layout, with the schedule as an appendix rather than buried in narrative.

Browse all 66 PlanScope report types and start a draft.

This is general guidance rather than legal advice. Check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.