Daylight and sunlight report in Merton

Merton's houses and long gardens

Merton is a borough of houses: 60.4 per cent of households live in a house or bungalow and 55.6 per cent own their home. Detached homes across the borough sell for an average of 2,338,085 pounds, so owners tend to extend rather than move, and neighbours defend their light.

Houses on generous plots tend to have long rear gardens, and the Greater London Authority's land-use survey put domestic gardens at 27.2 per cent of the borough. A big garden is not a free pass for a tall extension. Overshadowing of the neighbour's garden is one of the tests, and a two-storey side extension on a north-facing boundary can cast shade over the best part of an adjoining lawn.

The council's Borough Character Study shapes what officers expect on a street. We read it with the checklist, so that the form we test is a form the borough already supports.

Heritage controls in Merton

Merton has 28 conservation areas, and Historic England lists 243 entries in the borough, with 3 scheduled monuments. Check the council's own planning map for your road before you assume permitted development rights apply.

Inside a conservation area officers look closely at roof form and height, and a lower roof is also the simplest fix when the daylight result is marginal. If your house is listed the design may have little room to change, and then the report becomes the evidence that explains why the proposal is acceptable as it stands.

Merton's record on householder applications

Merton decided 759 householder applications in the latest published year and granted 92.9 per cent. Only 85.2 per cent were decided within eight weeks or an agreed extension, so allow for slower handling and make the application complete from day one.

Smaller schemes of up to nine homes were decided less quickly still, with 82 per cent on time. A report that satisfies the checklist at the first look takes out one reason for a delay. If the scheme is larger than a house extension, our planning consultant service in Merton can run the wider application.

How we produce the report

A measured survey of your house and the neighbours' elevations gives the window positions and heights. We build a three-dimensional model of the street as it stands, add the proposal and run the tests: vertical sky component at each affected window, average daylight factor in the rooms behind them, annual sunlight hours where orientation requires it, and hourly shadow diagrams for gardens.

The report sets out each result in a table and explains the shortfalls in plain English. London policy asks for appropriate light in context, and the BRE guide is advisory, so a few modest shortfalls in a dense street can be acceptable if the argument is made. A second technologist, not the one who built the model, checks the geometry before issue.

Our planning drawings in Merton come from the same model, so the report and the drawings never disagree about a ridge height.

Fee and next step

There is no list price, because the quote depends on the number of windows to test and the site. You receive a fixed fee after the free constraints check. Send us the address and a sketch.

Our daylight and sunlight overview describes the method, and the architectural drawings page for Merton lists the rest of what we do in the borough. Nearby boroughs ask for different things: see Sutton and Lambeth.