Plastic: not just a pipe dream

Richard Eddy of Polypipe offers advice on the best way to specify and use plastic-based systems on brownfield development sites.

This year, the housing crisis has been high on the news agenda, following the release of the Government’s highly anticipated Housing White Paper, and with housebuilding being a key issue in the recent elections. One of the Government’s key recent initiatives has been to propose a Brownfield Register, so developers can secure ‘planning permission in principle’ on previously used sites from local authorities.

While brownfield sites have been pushed for over 20 years by various governments and departments, progress has been slow, with issues such as land remediation costs and design issues hampering developments. But, every year that passes with usable plots of land lying dormant, the pressure to get building increases as the demand for new houses creeps up. As reported in 2014 by Building Consultancy Daniel Watney, there are 10,000 hectares of brownfield land suitable for housing around England alone, which would support 467,000 homes.

Many developers are reluctant to take a risk on brownfield sites unless there is the opportunity to dictate more favourable terms at the outset of building, such as allowing higher density developments to increase the viability of a project. Often, the existing infrastructure in and around the site needs to be upgraded and developed to provide new modern access to previously used sites, which adds to the outlay of any project.

Many developers are reluctant to take a risk on brownfield sites unless there is the opportunity to dictate more favourable terms at the outset of building, such as allowing higher density developments to increase the viability of a project. Often, the existing infrastructure in and around the site needs to be upgraded and developed to provide new modern access to previously used sites, which adds to the outlay of any project.

One of the biggest issues facing developers at the outset of a brownfield site development is getting the drainage system right, in order for new housing units to be able to connect into existing sewerage networks.

Brownfield sites can cause headaches for designers and contractors alike, but using materials such as plastic piping can produce quicker installation times, onsite design flexibility and long term durability, offering developers the peace of mind to push ahead. Using plastic systems can also help to mitigate the prohibitive costs associated with building on brownfield sites, and can offer practical solutions to complex design challenges.

Assessing the ground conditions across a brownfield site is, unsurprisingly, a crucial place to start. It is important that the topography of the ground is fully evaluated and that damaging chemical elements such as petroleum residues and tar deposits are removed during remediation.

By using products that hold the correct approvals, the risk of chemical degradation to the product is vastly mitigated. Plasticbased foul and surface water drainage pipes are designed to accommodate normal ground movement, and are tried and tested in all conditions to meet the required industry standards.

Importantly for brownfield sites, many plastic products are fully adaptable and compatible with existing drainage and sewer systems that may be encountered within brownfield sites, and are designed with a wide range of easy to use fittings and ancillaries. In addition, using plastic piping is ideal on sites where developers need to rely more on components manufactured offsite. Due to the often restrictive space of brownfield sites, transporting ready-made sections of a system to be installed directly onsite can make a big difference.

Plastic is inherently lightweight, helping to reduce the costs of major plant equipment required on site, which also helps to improve health and safety conditions for contractors.

Once the below ground system is installed, the resulting housing units will benefit from the huge variety of above ground drainage options plastic piping can provide. Whether in an individual house unit, or in a high rise building project, the advantage of plastic plumbing is that its use can ensure the development can continue at speed

For hot, cold and heating applications, plastic plumbing is incredibly versatile. Almost all eventualities of a building design can be accommodated using plastic piping, offering longer pipe lengths and coils with trusted fittings technology that reduce the need for more complex jointing techniques and hot works associated with traditional materials such as copper. With the construction sector bracing itself for a skills shortage over the coming years, plastic-based solutions will be invaluable to ensure a smaller workforce can keep a project on track.

Polybutylene pipe provides users with many benefits, and greater flexibility. It is ideal for most domestic hot and cold water plumbing and heating systems, offering exceptional durability and long-term performance, which has seen it become the preferred material choice for today’s building projects.

Polybutylene has excellent resistance to freezing temperatures, which helps it to maintain durability in heating and water applications. This means that in the rare instance that water freezes within the pipe, the risk of a burst is greatly reduced. One further advantage is the high corrosion resistance of plastic piping, meaning that the use of hard or soft water, depending on your location, will not cause a long-term issue.

As more people want to move to major towns and the Government continues to push developers to find solutions to use brownfield sites more regularly, supply chain manufacturers will continue to promote time saving, cost saving systems that can make life onsite easier for contractors. Ensuring that a drainage system is correctly installed on site is one of the key components of getting a brownfield site development off the ground. Using materials such as plastic offers greater flexibility and adaptability to conditions on the ground, without the risk of product and system failure.

Richard Eddy is below ground drainage product manager at Polypipe.