As the Garden Museum launches a campaign to increase the right to sunlight in public gardens and open spaces, LPG Director Helen Monger explains the importance of natural light, and efforts being made to defend it.
In June 2021, a development application for 8 Albert Embankment, adjacent to the Garden Museum, was turned down at the planning inquiry. The proposed 26-storey luxury flats would have overshadowed Old Paradise Gardens, one of many parks listed on the London Parks & Gardens Inventory. This historic little public park once formed part of the churchyard of St Mary’s Church, in which the Garden Museum is housed today, and was one of the first parish spaces to be converted into a park under the Metropolitan Open Spaces Act of 1881.
The Garden Museum had objected to the application on the basis that the high-rise flats would have plunged the park into 22 hours of shadow, for half the year; but although the application itself was rejected, the Museum’s reasons for objecting were ignored, along with many others. The inquiry found that the proposals were ‘compliant with current guidelines which require two hours of sunshine per day as measured on 21March’. Staff and researchers at the Garden Museum were shocked by the revelation that standards for amenity space were so poor. On 21 March 2022, they launched a campaign to address this issue in planning policy, supported by the LPG.
Why does natural light matter?
Guidance set by the British Research Establishment Trust (BRE) states that, on the Spring Equinox, sunlight must fall on a public garden for a minimum of two hours on at least half of the amenity area. The original intention of this guidance may have been well-meant, but the ‘two-hour rule’ has become a guide for planners across the UK who seek to deliver no more than this basic minimum.
The Garden Museum’s publication, The City that Sold the Sun, articulates the importance of access to quality green spaces with natural light. Professor Sir Sam Everington, a GP in Tower Hamlets, states that half of his patients are deficient in vitamin D, which is produced by the human body as a response to sun exposure. Vitamin D deficiency can lead to a loss of bone density, and at the extreme end of the scale this can lead to rickets and cause bone deformities in children. Tower Hamlets is an area of high deprivation, and is one of the most densely populated areas of the UK; the health impacts of lack of sunlight fall more harshly on already deprived communities.
As well as human concerns, there are real issues with lack of daylight for horticulture and nature more widely. Growers need more than six hours of sunlight per day to grow vegetables, and shaded gardens can support a less diverse range of plants. Lack of sunlight also influences temperature, and therefore insect activity; many major pollinators require a certain temperature before they can become active.
Tall buildings not only shade parks from daylight, but create issues of light pollution at night too. Government guidance on light pollution states that “artificial light provides valuable benefits to society, including through extending opportunities for sport and recreation”, but that it can also “be a source of annoyance to people, harmful to wildlife and undermine enjoyment of the countryside or the night sky” (1).
One rule for us and another for them?
High-rise development brings both lack of sunlight during daytime hours and light pollution at night, yet the current thrust of UK development policy is to deliver a denser urban environment. This naturally leads to proposals aiming to build upwards, but the placement of multi-storey buildings is restricted by efforts to conserve landmark views across the capital. Since 1937, the City of London Corporation has operated a policy known as the ‘St Paul’s Heights’ to protect a number of famous views of the Cathedral. More recently, the London View Management Framework has defined protected views across London’s cityscape; indeed it was because of the view from Primrose Hill that the planning inquiry turned down proposals for 8 Albert Embankment.
Tall buildings not only
shade parks from daylight,
but create issues of light
pollution at night too
Local Authorities, however, must reach stringent targets set by central government and provide necessary housing, and this often leads to the identification of specific areas for tall building development clusters – with a resulting tacit acceptance of loss of access to daylight in these areas. Mathew Frith, Director of Policy and Research at the London Wildlife Trust, points out that clusters of tall buildings also cause additional cooling and disruptive wind-tunnelling effects, which provide a more hostile growing environment and can kill plants through desiccation and windburn.
The introduction to the Government’s Rights to Light (2) research published by the Law Commission in 2015 begins by defending the human need for natural light: Natural light inside buildings is immensely important for comfortable living and working. We like and want natural light in our kitchens, and at our desks; people like to have a window seat and most people thoroughly dislike a windowless room. The amount of natural light that a window lets in depends upon what is outside that window, and particularly upon the proximity of other buildings.
However, the report goes on to prioritise development over this need: The legal system recognises the value of natural light inside buildings, but because available space is finite it has to strike a balance between the importance of light and the importance of the construction of homes and offices, and the provision of jobs, schools and other essentials.
Although these statements relate to natural light in buildings, it is clear that the deprioritisation of natural light is applied to green spaces as well as to dwellings.
Setting new standards
There is limited quantitative evidence to demonstrate the need for access to sunlight; this is the challenge thrown at those campaigning for better protection in the planning process. All the authors of the Garden Museum’s report accept that their evidence is in part anecdotal, but they suggest a precautionary approach on the basis of this evidence. Our environment is too fragile and too important to lose through lack of prior consideration.
On that basis, the campaign has called for the GLA to amend its guidance. The following statement has been suggested by the LPG as an amended policy.
All developments should seek to maximize access to natural daylight in public open spaces for the benefit of everyone. In general it is expected that public open spaces should receive a minimum of six hours on at least 50% of the area at the equinox. It is expected that all developments should demonstrate how they will protect:
• daylight for more than two hours on all parts of a children’s playgrounds and other outside sporting facilities such as fitness areas, football pitches etc, to maintain the amenity value; and
• the future sustainability of existing horticultural planting schemes based on an ecological assessment of biodiversity and climate value, in accordance with the Natural Capital Accounting methodology agreed in the Mayor’s London Plan.
There will also be a presumption against supporting a proposal which:
• reduces existing daylight access below the six-hour limit; or
• further reduces access to daylight in a space which already fails this standard.
George Hudson, Green London Curator at the Garden Museum, said: “We are grateful to have the support of London Parks & Gardens in our campaign to protect London’s green spaces from being cast into shadow by new tall buildings. Recently, our campaign has attracted the attention of assembly members at City Hall, and we are in conversation with them. The importance of sunlight is often understated, if not forgotten about completely.”
The LPG will update members on the progress of the campaign, and will continue to support this policy initiative.
2 https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment data/file/391683/44872 HC 796 Law Commission_356_WEB pdf