Roofspace Solutions’ innovative off-site manufacturing (OSM) product i-HouseTM – which guarantees a waterproof dwelling in five days – is being implemented in a Lovell Homes site in Norwich. The result is a 35% timesaving compared to traditional building methods.
Leading partnerships housing expert, Lovell Homes, prides itself on transforming communities across the UK. As part of its commitment to innovative residential construction and regeneration projects, it chose to embrace i-HouseTM OSM technology by Roofspace Solutions during the building of its latest development.
Crown Meadows in Norwich comprises two, three- and four-bedroom homes. Construction began in June 2020 and is planned to complete in two years – or possibly sooner as Roofspace Solutions’ i-House can create a watertight standard house shell in under a week, while combining quality, speed and safety.
In addition to speed, Lovell Homes specified i-House in 15 of the 69 Crown Meadows plots as part of its aim to reduce waste and dust, while also minimising the risk of accidents.
A new way of working
The i-House uses a bigger and lighter variant of the aircrete block, which are lifted by crane and assembled in a similar sequence to a timber frame build. This results in a much faster construction process than a traditional build.
Intended for domestic property construction of up to three storeys, i-House consists of inner leaves of external cavity walls, separating walls, floors, lintels, cavity closures, insulation and roof trusses, with the inclusion of soffit and fascia for the internal skin of the property.
Roofspace Solutions is working alongside supplier H+H to design and produce the large-scale Celcon Elements, which are manufactured from the same material as the aircrete blocks. This gives them the same advantages, such as outstanding thermal performance and reduced heat loss at thermal bridges.
Manufactured with a width of 600mm and a thickness of 100mm, Elements are designed to be craned into place onto a bed of mortar on standard foundations. Blocks are joined using thin-joint mortar with 2mm (3mm) joints, providing an extremely airtight finish.
The fact that the solution is manufactured off-site, and larger elements are constructed prior to being delivered to the site in Norwich, means less waste and dust is created for workers. This results in a safer and cleaner working environment. Furthermore, workers on site are not exposed to chemicals.
Crucially, as the homes are watertight in under a week, it has increased Lovell Homes’ construction programme, allowing internal trades to begin their work sooner than with a traditional build.
With the additional consideration of building during the time of Covid-19, the OSM solutions enhance Lovell Homes’ stringent social distancing protocols. At the Crown Meadows site, approximately four builders will be able to build six houses in four weeks, with i-House increasing the output per person.
The i-House package also includes floor cassettes and JJI-Joists provided by Pasquill, sister company of Roofspace Solutions, due consistency of quality and supply and a nationwide delivery service. A total of 60 cassettes will be provided to the same 15 OSM plots on the Crown Meadows development, with each home’s first floor containing an average of 3-4 cassettes.
The Pasquill cassettes, which are made with chipboard and softwood, are ideal components to work alongside the i-House as they facilitate faster timescales and dramatically speed up the erection process. This increasingly popular method allows the contractors to install the floors in one day with little on-site work required.
The cassettes are also installed with Pasquill’s JJI-Joists, also known as I-beams, to create ‘quiet’ floor solutions and consistent dimensions provide extra stability. They do not need insulation to gain compliance with Building Regulation Part E (sound) when installed at 400mm centres and above. They are lightweight, stable, easy to run services through and cost effective.
Building better results
Paul Terry, Managing Director of Roofspace Solutions, said: “The construction industry is facing many challenges. The only way we will be able to ‘build back better’ and meet government and industry targets for housebuilding is by working together and embracing new technologies.
“The Crown Meadows development is coming along well, and we’re glad that Lovell Homes is already experiencing the time-saving benefits from i-House and Celcon Elements. We’re enjoying working on this project with a developer who has such high standards and look forward to seeing the site completed.”
Chris Gray, Senior Construction Site Manager at Lovell Homes, said: “I believe Crown Meadows will be a much quicker build, from start to finish. Of course, it’s difficult to compare like-for-like, but recently a plot went from being a concrete pad to us laying the roof tiles within two weeks – everything fits like a Lego set!
“Based on the success so far, it’s now our ambition to bring in the development a few months ahead of schedule. For the construction industry, it’s another tool to help us get the job done well and meet the demand for housing – while reducing waste and accidents on site.
“The fact it allows us to make a property watertight so quickly has immediate benefits, such as completing the show home quicker, allowing us to drum up local homebuyer interest sooner. Overall, I think this is a flexible solution that would have really useful applications during the winter or further north, where it typically rains more.”
Roofspace Solutions has been part of the Saint-Gobain Group since 2018, as part of its Off-Site Solutions division.
For more information on i-House, click here