Daylight and Sunlight Assessments in Milton Keynes

In Milton Keynes the daylight question usually arrives in one of two ways. Either a small housing scheme of five or ten homes in Bletchley, Wavendon or one of the edge-of-city sites has drawn a request from the council, often because of mature trees on or around the site, or an extension in one of the older towns, Stony Stratford, Wolverton or Newport Pagnell, sits close to a neighbour's window. The grid-square estates and the newer expansion areas bring their own version: houses spaced more tightly than the city's original layouts, with gardens that need to get enough sun.

Trees come up more often here than almost anywhere else we work. Milton Keynes City Council protects its landscape structure carefully, and officers want to know that new homes beside retained trees will be well lit, so that the trees are not under pressure later. A report that models the trees properly, in leaf as well as bare, answers that directly. Our main daylight and sunlight assessment page explains what a report contains.

Recent daylight and sunlight assessments in Milton Keynes

Wavendon: seven shortfalls turned into a scheme that met the guidelines

Five new houses on a treed site at Wavendon, refused with light among the reasons. The developer needed to know whether the scheme genuinely worked, inside the houses and in the gardens, with a report that would stand up at appeal. With the trees modelled from the tree survey, seven rooms fell short, mostly through too little glazing rather than tree shade, and one garden fell just short beside a large retained ash. Extra living room windows, a rooflight, attic studies designated as storage and the removal of the ash brought every room and garden within the guidelines. The report was prepared for the appeal.

Duncombe Street, Bletchley: ten flats beside mature trees, modelled in leaf

A ten-apartment scheme already with the council, where Milton Keynes City Council was concerned that the nearby trees would leave the flats short of light. All ten apartments met the internal daylight and sunlight guidelines. To show clearly that the trees had been taken into account, we built the arboricultural survey into the model and tested the flats again on 21 June with the trees in full leaf, as well as on the standard March date. The final report answered the officer's concern directly.

Chepstow Drive, Bletchley: a pre-application check on ten new homes

At pre-application stage the council asked for a daylight and sunlight assessment of a ten-home site at Chepstow Drive, in particular how the first plot related to a house on Wincanton Hill. We tested internal daylight, the gardens and that neighbour. The Wincanton Hill house met the BRE guidelines, as the only affected window serves a non-habitable room. Inside the new homes most rooms met the targets; a first-floor bedroom and one other room fell short, and we advised enlarging the windows to both. The gardens were tested for sun on 21 March.

What Milton Keynes planning officers look for

Milton Keynes City Council decides applications against Plan:MK, the Local Plan for 2016 to 2031, adopted in March 2019. A replacement, the MK City Plan 2050, is in preparation; until it is adopted, Plan:MK applies. Its design policies expect development to fit comfortably with its surroundings and to protect the amenity of neighbouring occupiers, with loss of daylight and sunlight one of the impacts officers weigh.

For new housing, the council's New Residential Design Guide SPD covers layout and the spacing between buildings, which has a direct bearing on daylight. There is no separate householder extensions SPD, so extensions are judged against Plan:MK's general design policies. The technical benchmark is BRE BR 209 (2022 edition), and the BRE guide's advice on trees matters here more than in most places: our article on the BRE guidance on trees explains how they are treated.

The documents are on the council's planning policy pages and its adopted SPD page.

When you need an assessment in Milton Keynes

• Small housing schemes in Bletchley, Wavendon and the edge-of-city sites, especially where mature or protected trees are retained
• Resubmissions and appeals where light was among the reasons for refusal
• Pre-application requests to check how a new plot relates to an existing house
• Extensions in the older streets of Stony Stratford, Wolverton and Newport Pagnell, where neighbouring windows sit close to the boundary
• Infill houses within the grid-square estates and tighter plots in Broughton, Kingston and Oakgrove

How we work

We build a 3D model of your scheme, its neighbours and any significant trees, run the tests and share the results before the report is written, with practical fixes for anything that falls short. The fee is fixed and agreed up front, and the report usually takes 4–5 working days from final drawings. For neighbours, the tests are:

• Vertical Sky Component (VSC): how much sky a neighbouring window can see
• No-Sky Line (NSL), or daylight distribution: how far daylight reaches into the room
• Annual Probable Sunlight Hours (APSH): annual and winter sunlight to windows facing within 90 degrees of south
• Sun on ground: whether at least half of a garden gets two hours of sun on 21 March

For new homes we use the BRE 2022 internal daylight and sunlight method. Our VSC, NSL and APSH page and BRE guidelines page give the detail.

Frequently asked questions in Milton Keynes

The council is worried our trees will shade the new homes. How do you model them?

We take the trees from your arboricultural survey and test the homes in March and, where it helps, in June with the trees in full leaf, so the report addresses the officer's concern directly.

Why would a bedroom meet the target when the living room below does not?

Living rooms have a higher target than bedrooms, and upper-floor windows see more sky. Small changes to living-room glazing usually close the gap.

Light was one of our reasons for refusal. Can a report help at appeal?

Yes, if it is thorough and consistent. We test every room and garden, propose fixes, and report all the results so an inspector can rely on them. We do similar work in Cambridge.

Get a fixed-fee quote

Send us your drawings, tree survey and any council comments through our contact page, or get an instant figure from the price calculator. You can also call Nick on 01962 809155 or email nick@sunlightassessments.co.uk.