From factories to abandoned warehouses developing a brownfield site can be daunting. It will always involve dealing with buildings or land that has had a previous life, or multiple lives. But with the right approach you can successfully build new homes on brownfield sites. Transforming these sites can bring huge environmental, social, and economic benefits, as well as be looked upon favourably by planners.
What is a brownfield site?
Brownfield sites are land that has already been developed in some way, but that is now considered redundant, underutilised or in need of re-purposing. We are developing one site for five houses, that was previously home to 20 garages and an outdated office building. Brownfield sites are often tucked away in towns and cities but also crop up in rural areas. Garden plots do not count as brownfield sites.
The challenges of developing brownfield sites
Brownfield sites rarely come without risk and can throw up a myriad of unforeseen challenges and surprises.
Often having previously been home to industrial or commercial buildings, they can be hazardous and in need of decontamination and/or demolition, which can be costly. Sites may be awkwardly shaped or located and pose design challenges. Some have limited access or working space, and some are still attached to other buildings.
Brownfield sites are often surrounded by other sensitive buildings, such as homes, offices, or shops, adding further complication (for example, the need to avoid dust, noise or congestion).
Brownfield land can be more challenging than the buildings on it. There is almost always contamination in brownfield land (even if only from a demolition process). This contamination is often hazardous—asbestos, heavy metals and hydrocarbons commonly appear in the soil of such sites. Harmful gases to consider include methane, carbon monoxide and the radioactive gas, radon.
Hazards in the land can often be hidden. There may be a network of services/utilities/drainage, old storage tanks, foundation structures, or made ground (fill that is mainly rubbish). It is not uncommon for archaeological remains to present, even if historic checks have been made. If these are of significance, they can cause a development to be held up or halted completely.
While brownfield sites can be easier to get planning permission for, it’s likely there’ll be complex planning requirements that must be followed.
The benefits of developing brownfield sites
Investing in the development of a brownfield site is a more responsible and sustainable approach to repurposing land. Doing so not only helps protect and preserve greenfield sites, but new ecology-friendly features (such as tree planting, gardens, ponds, bird boxes and bee bricks) increase biodiversity in what were often previously poor habitats.
Further environmental benefits come when new homes built on brownfield sites are highly energy-efficient and are fitted with renewable energy generation and air-source heat pumps, electric vehicle charging points and systems to reduce water waste.
Building on brownfield sites also offers social and economic benefits to the surrounding cities and towns. Redevelopment of brownfield sites can improve the safety and look of neglected buildings while preserving the traditional character of the area, can inspire community regeneration and local employment opportunities, and reclaim derelict land for housing and new social areas.
The use of brownfield sites is encouraged by the UK Sustainable Development Strategy, which promotes social progress and equality, environmental protection, conservation of natural resources and stable economic growth.
How to ensure the benefits outweigh the challenges when you’re looking to build new homes on brownfield sites
With a considered, systematic approach that holds sustainability, safety, and attention to detail at its heart, the potential of brownfield sites can be unlocked for the benefit of everyone.
Developing brownfield sites requires vision. Rather than a blank canvas, they often throw out unique challenges, and opportunities, that demand creative thinking and determination to build something out of the ordinary.
Brownfield sites must be thoroughly assessed and (preferably) intrusively investigated before any development can be considered. The usual process is for an environmental consultant and/or a geotechnical engineer to carry out a site visit (for a Site Walkover Survey) to get a general impression of the situation.
This is followed by a Phase 1 Assessment, a desk-based study that considers land quality and assesses a wide range of data sources that will inform what previous impacts there have been on the land. The outcome of this assessment is usually a series of recommendations for further specific tests, the results of which then allow engineers and designers to formulate a strategy to tackle any issues that are detected.
If contamination is discovered, as it was at our development in Weston-Super-Mare, contaminated ground can be removed and replaced with clean soil, which must then be independently certified as uncontaminated and approved by the Planners before work can continue.
In the case in Weston-Super-Mare, we also pumped out a hidden, buried oil-tank and backfilled it with concrete to neutralise it. This site had large areas of poor-quality made ground that was unsuitable for normal foundations and meant we were forced to use expensive piled foundations that had to be installed very close to neighbouring homes.
Working closely with specialists is key. From sound engineers to geotechnical surveyors to structural engineers and piling contractors, investing in, and responding appropriately to expert advice will help ensure the success of your development.
Do you need planning and building expertise to help realise the value of your brownfield site development? Talk to us.