The SIG I-House System, based on the storey-high aircrete panels, delivers a complete house shell with weathertight roof and wrapped in insulation in just one week and is the result of a unique collaboration between H+H and SIG Off-Site. It is one of a number of building types being trialled by Barratt Homes who are keen to experiment with new methods of construction that offer improved speed of build.

Context

Norton Farm, located less than a mile from Bromsgrove town centre, south west of Birmingham, is a development shared between Barratt Homes and David Wilson homes, consisting of a total of 316 units.

Product supplied

The SIG I-House System is being used for 164 of the Barratt Homes development plots.

The Norton Farm development is part of Barratt Homes’ final trial stages of the SIG I-House System which has seen several other developments completed across the Midlands.

Each unit is constructed by a three man gang and a crane operator from SIG Offsite. This has solved one of the critical challenges faced by Barratt Homes in the Midlands, with a shortage of skilled labour creating a delay in construction. A crane lifts each Celcon Element into place where is it secured using a fast-setting mortar specifically created by H+H for use with Elements.

By using the I-House System the external brick façade has been taken off the critical path allowing the ground floor, first floor and roof to be completed, finished and wrapped in insulation prior to bricklayers arriving on site.

A bespoke scaffolding system has been created to allow bricklayers enough space to operate while the scaffold remains in place.

The walls achieve a U-Value of 0.27W/m2K - similar to that in a traditional build - with roofs achieving 0.8W/m2K and floors 0.2W/m2K.

Outcome

“It’s simply one of the best offsite systems we’ve seen. It’s basically block-work erected in a different way which gives us flexibility on site. If you require any design alterations while on site, you can treat it like a traditional build – if you need an additional window suddenly, you can do it; timber frame can’t be altered due to the structural calculations changing.”

- Steve Cartwright, Director West Midlands, Barratt Homes Construction