The word prefabrication often conjures up images of the kind of modular housing built in London, Birmingham and Bristol after World War II, but off-site production is a concept now being embraced within modern construction too. As a means of improving the efficiency of a building project and reducing costs, the scope for prefabrication is expanding all the time. Here, Ken Percival, Managing Director for Potterton Commercial explains why prefabricated heating solutions are increasingly popular in the commercial arena.
In today’s ‘perform or pay’ climate, where most building contracts include a liquidated damages clause entitling the client to compensation should a project run over schedule, effective site management is crucial in protecting the profitability of a development. To reduce time spent onsite and make the construction process more efficient, many architects and specifiers are looking towards prefabrication as a way to minimise the risks, and costs, of delays.
In terms of the off-site production timeline, prefabricated heating solutions are relatively new but are poised to revolutionise commercial installations and replacements. Greatly reduced installation times mean jobs which could have taken up to a week to finish can now be completed in one or two days. This makes prefabricated heating units suitable for both commercial applications, where time is limited, and public sector buildings, where access to the site can be restricted such as in schools. With just external services to connect and distribution pipe work to operate once the module is in place, the plug and play concept is one that is appealing to those working to tight deadlines.
Aside from the simplicity of installation, another benefit of prefabricated heating solutions is the low risk factor. As the modules are prepared in a factory, the result is a high quality, engineered product. With the integrity of the prefabricated unit guaranteed, engineers installing the product do not need to be concerned with missing parts or components, or the on-site delays incurred. Each element of the system is fitted and checked before leaving the manufacturer. Time spent preparing the module or skid in the factory is much less than if the same components were put together on-site, thus also saving on the installation cost and keeping the project on schedule.
While the problem of skills shortages in the buildings and construction industry persists, off-site production allows site managers to employ fewer labourers as work which would have been completed on-site has already been done. In terms of prefabricated heating solutions, installing a system can be completed by fewer engineers – manpower is required to position the skid in the boiler room, but connecting the module is a simple job for just one or two engineers. By using fewer workers per installation, prefabrication saves on labour costs for the project, and means that operatives from different trades are less likely to be in each others way.
When specifying a prefabricated heating solution, the decision must be made early on in the process to ensure the product is correct for the application. Access should be a primary concern – how will the module be transported to the boiler room? Some units have forklift points and lifting eyes. Will the module fit through the doorway/opening to the boiler room? Most prefabricated heating solutions are designed to be appropriate for a standard doorway but potential problems may arise if the door is smaller. Can it be easily manoeuvred into position? Some prefabricated solutions have mobility features which allow for the clipping of wheels or mechanical skates to the frame to make transportation smoother. Site surveys and careful planning will ensure that access is not an issue.
Suitable for new builds, retrofit and refurbishment projects, and available in heat only and hot water and heating options, prefabrication has a lot to offer the modern building engineer.
Case study – Ipswich Hospital
In 2006, the recently extended Diabetes Centre at Ipswich Hospital was fitted with a prefabricated heating module – Potterton Commercial’s Paraskid. Senior Mechanical Engineer and consultant on the project, Robert Diamond from Ingleton Wood LLP, discusses why he chose a prefabricated heating solution:
“The Diabetes Centre at the Ipswich Hospital was recently extended; the size of the clinic was doubled from 276m2 to 636m2. The new extension was to include a new education and waiting area, as well as new clinical rooms, heated using an underfloor system. The existing heating system was not adequate to provide heating and hot water for the larger space and having discussed all the options for this NHS Trust project, we decided that a prefabricated solution would be the best specification. We looked at the prefabricated heating packages available on the market and decided that the Potterton Commercial Paraskid was the right solution for the job.
“As the hospital extension was to have a completely new plant room, commissioning and designing the installation to fit with the prefabricated module was simple. The boiler room was designed to match the dimensions of the Paraskid, offering a neat and tidy installation.
“We specified a Paraskid with two 80kW Paramount condensing boilers. The boilers are extremely high efficiency, condensing units which present improved fuel usage which not only reduces CO2 emissions and meets the requirements of Part L, but also offers the hospital savings on running costs. They are perfect for the new underfloor heating system as the lower floor temperatures mean a higher efficiency as the condensing mode kicks in.
“I had never specified a prefabricated heating solution before but the Paraskid ticked all the boxes for the Ipswich Hospital project. It was both cost and time effective and I would not hesitate to use a prefabricated heating solution again in the future, whether for a new build or refurbishment project.”
The Paraskid is a skid mounted package containing all of the components pre-assembled for simple on-site positioning and connection of a heating and hot water condensing boiler plant solution. Designed to meet the demands of both new build and refurbishment projects, the Paraskid is the first prefabricated boiler plant to offer two options – a heat only solution and a heating and hot water solution, which combines the Paramount boiler with a Heatrae Sadia Megaflo storage water heater. All models include control panel, pressurisation set and expansion vessel, modulating pumps, dosing pot, condensate neutralisation, and all pipework headers. These options, combined with the range of outputs available, give specifiers a comprehensive choice of Paraskid plant, making it a versatile prefabricated solution.