If your property was built before 1970, the chances are that your drains are made of something other than plastic. Depending upon the era in which the property was built, dig up your garden and it is possible that you could find clay, cast iron, asbestos cement or even pitch fibre drains. All of these substances were the chosen materials for underground drainage at one time or other in the past one hundred years. So why has PVC become the dominant force in UK domestic drainage manufacture?
Firstly, the material itself has properties that make it well suited to the rigours of a drainage system. PVC is now widely accepted as an excellent building product due to the fact that it is non-corrosive in nature – it is unaffected by most chemical, electrolytic and ionic corrosion, meaning that PVC pipes therefore can resist most kinds of acids, alkalis, oxidizing agents, oils and domestic effluents.
The smooth internal bore of a PVC pipe is achieved by using highly polished metal moulds in the extrusion manufacturing process. This smooth bore automatically provides a natural resistance to blockages, and enhances the flow rate of a pipe by as much as 30% when compared to other materials. Providing PVC drainage pipes are installed at a correct fall this ensures that the pipe itself is self-cleaning, making it an essentially maintenance free product.
PVC pipes are lighter than all of the alternative materials that have been used down the years. This has two advantages. Firstly, it is much easier to transport and store, making it a more economical material for builders merchants and DIY stores to handle and deliver.
Secondly, the comparatively high strength to weight ratio of the product means that it can be manufactured and utilised in longer lengths – 6 metres (20 foot) being the norm. This in turn means that the system can be assembled with far less joints required than with traditional materials 火炭通渠 , giving less opportunity for any possible leaks to occur.
PVC pipes also have self extinguishing properties, eliminating the need for any fire proof treatments, improving health and safety in terms of site risk assessments.
The one drawback that PVC pipe manufacturers have yet to fully resolve has nothing to do with its use – it is rather the public perception of what can be done with the material at the end of its useful life. Plastic is notorious for being a “non-degradable” product, and is often seen as environmentally unfriendly. In recent years however there is a growing trend for the use of recycled PVC in a variety of manufactured products.
The most notable success has been the growth in demand for recycled PVC garden furniture and traffic bollards, which have been adopted by a number of local authorities. Some companies are also now manufacturing UPVC windows made from recycled pvc products, although the high cost of cleansing and manufacture is currently a barrier to wholesale adoption of these products.