By James Mead, projects director at Saint-Gobain Weber.
If you ask most people what their house is made of, the chances are they’ll tell you it’s made of bricks. In fact, around 70% of the UK’s new homes are built with a brick façade proving that this traditional style has retained its popularity since 7000BC, when the people of Jericho made the first bricks from mud and dried them out in the sun for hardening.
Today’s bricks are kiln dried and are much heavier than a mud brick – so the costs in terms of freight, emissions, weight, space, and storage are significant. The other pressing issue with bricks is bricklayers: They’re in very short supply and laying bricks is such a skilled craft, it takes a long time to gain the experience to do a decent job.
With a call for bricklayers to be added along with lorry drivers to the Government’s Shortage Occupation List, and existing bricklayers charging a premium, we need to find a way to construct buildings that are traditional in style but modern in construction.
Those building homes in the social housing sector also have another concern: the Government’s Affordable Homes Plan, delivered through Homes England, specifies that the projects it funds must contain a minimum of 25% MMC. It also sets a measure against which MMC projects will be assessed – the Pre-Manufactured Value (PMV). This is the financial proportion of a project’s gross construction cost through pre-manufacturing. To pass Homes England’s MMC test you need to have at least a 55% PMV.
To calculate a building’s PMV, each element that is delivered through an MMC process or product will add to the overall percentage. There are seven categories awarding percentage points. For example, in category one is ‘Pre-manufactured 3D primary structural systems’ like a volumetric modular housing unit. This will give you the highest percentage. In category three ‘Pre-manufacturing components (non-systemised primary structure) components’ – such as beams, staircases or trusses would also boost your percentage.
Category six deals with building products and systems that reduce labour on site and improve productivity. One area where it’s easy to specify a PMV improving element is using a modern alternative to traditional brickwork.
Encouraging MMC in the private sector
Of course, it’s not just in the social housing sector where the principles of MMC and increasing the use of off-site manufacturing are important. Private housing developers must also adopt MMC to play their part in the fight against climate change.
The construction industry is responsible for 38% of CO2 emissions, so any products that can reduce both wastage and HGV deliveries to sites are going to make a huge impact on this figure. MMC also addresses labour shortages by using products made in factories without the need for specialist skills, and off-site manufacturing reduces construction waste which accounts for 59% of waste produced in the UK.
Traditional in appearance, modern in application
Saint-Gobain Weber has developed weberwall brick to help bridge the gap between traditional and modern methods of construction. We have developed a façade alternative that gives the appearance of brick but can be fitted without the need for specialist labour on site. Once applied, it feels and looks just like the real thing.
Ideal for developments or refurbishment projects where planning permission requires a brick façade, weberwall brick is lightweight and quick to apply taking around 17 minutes to install 2sq m. Cladding the equivalent area in brick slips takes just under an hour and when the whole build is taken into account it can be up to 50% faster than using a traditional brick slip
The lightweight brick slip system can be applied directly to the substrate with a specially formulated render. It is then pointed in the same way as a standard brick so, once installed, looks no different to traditional masonry.
It can be programmed into CAD systems to minimise waste and is designed for use with the most commonly used MMC systems so ideal for steel, wooden frame and panellised systems. weberwall brick forms part of BBA approved systems and is suitable for new build or refurbishment projects where it can give a building a completely new look.
If developers are going to truly grasp MMC to combat the housing crisis through centralised funding, they are going to need to adopt creative and innovative solutions to increase their project’s PMV whilst conquering the multiple difficulties posed by today’s construction industry, weberwall brick is certainly up to the challenge.