Construction News visits the testing and R&D facility of a leading manufacturer to see how industry products are put through their paces against freezing temperatures, intense humidity and – crucially – fire.
The performance of building materials is under scrutiny now more than ever.
The Grenfell Tower fire has seen national media put the intricacies of external cladding and its fire properties under the microscope, while raising questions about how materials are tested and whether Building Regulations are fit for purpose.
Construction News recently paid a visit to one manufacturer’s research and development facility in Avignon in the south of France to see how materials are engineered and tested to ensure they meet specifications.
This facility, run by Etex Building Performance, the company that owns the plasterboard brand Siniat and the fire protection specialist Promat, has a wide range of testing stations to run its products through, as well as a large furnace to test fire properties – an area of great concern within the building community at the moment.
Before seeing the facility itself, though, Etex Building Performance business development director Nicola Chapman explains the rationale behind how the products are developed before the testing phase begins.
“We need to find ways to change how we build. For us, job productivity is key,” she says.
Etex Building Performance Siniat Promat Avignon plasterboard 2
“A lot of the time we create new solutions on paper that are hard to install. So we wanted to go to a real job site and understand what really happens, as here in the lab we’re great at theory and testing products.”
To that end, the company teamed up with the Building Research Establishment to conduct a time-and-motion study into plasterboard installation. The BRE has also been in the spotlight over recent weeks through its role in testing cladding for the government as part of the investigations surrounding the Grenfell fire
The Etex-BRE team chose a non-high-rise residential project in London with a number of standardised solutions and high levels of repetition across many small apartments.
“A lot of the time we create new solutions on paper that are hard to install. So we wanted to go to a real job site and understand what really happens, as here in the lab we’re great at theory and testing products”
Nicola Chapman, Etex Building Performance
BRE spent just under 280 hours observing the work that was done on site, looking at value-added activities (where actual building work was being done), non-value-added activities (time taken preparing materials, such as cutting) and wasted time (where workers were doing nothing due to errors, or while waiting for something else).
BRE found that value-added activity made up only 58 per cent of the time spent on a site, with 23 per cent non-value-added and 19 per cent waste.
In particular, BRE split the installation of Etex’s products into a number of detailed steps, observing each step on average eight times, and then assigning each step a length of time taken to carry it out.
“That’s incredibly valuable for us because we can see specifically where we can save time,” Ms Chapman says. “If we can take away one of those processes, we know exactly how much time that will save on a job site, and what that will mean for the installer or the main contractor.”
This information then informs what kinds of products Etex uses. By developing a plasterboard that is stiffer than normal, for example, it enables the installer to put a larger space between the metal supporting profiles, making the installation more efficient.
“In comparing our standard system with 450 mm centres to the stiffer product with 800 mm centres, we saw a 27 per cent increase in the speed of installation – which if we applied it to all the apartments would have resulted in 200 hours of job-saving, just by substituting one plasterboard for another,” Ms Chapman says.
With these goals in mind, Etex has to make sure the products comply with regulations, as well as hitting the performance goals that it sets internally.
“Individual components can get good results in a furnace, but will perform differently in reality”
Sebastien Segura, Etex Building Performance
With fire testing currently at the forefront of the industry’s mind, CN was given a behind-the-scenes look at the centre’s universal furnace, which is used to carry out 40-50 fire tests a year on both vertical and horizontal systems representing walls, floors and ceilings.
Interestingly, the firm tests complete systems here: Siniat plasterboards with holes drilled through them for pipes, which are then fitted with Promat passive fire protection to create an entire system – with insulation behind it in some cases – that would be fitted on a building in real life.
Etex Building Performance Siniat Promat Avignon plasterboard 1
“Individual components can get good results in a furnace, but will perform differently in reality,” explains Etex fire expert Sebastien Segura. “Here, the PVC pipe will melt inside the partition, but the fire-stopping material expands as the temperature increases to fill that hole and stop fire spreading.”
This is important, Mr Segura says, as if you drill a hole through a fire-rated material, you have then created a break in that fire protection that will need to be mitigated against.
The company pre-tests its systems here before they are certified externally for use on projects, using the R&D facility to prove that they work internally before going through the process of certification.
It wasn’t just fire testing on show, though.
Etex also has what it calls a hotbox / coldbox, two large boxes that sit side-by-side and allow it to test its materials for thermo-efficiency, measuring heat transfer and vapour transfer.
The boxes were tailor-made for Etex’s requirements at a cost of approximately €700,000, and the company claims that it is the only facility of its kind in Europe that can test at such a large range of temperatures.
That range? The cold box can drop to -30 deg C, while the hot box can reach up to 50 deg C – with relative humidity at almost 100 per cent or 0 per cent depending on the test.
To carry out the test, Etex builds a wall inside a frame before sliding it into place, with the boxes completely enclosing both sides of the wall. It can also insert windows and doors into the wall to better understand what happens around those openings.
Etex Building Performance Siniat Promat Avignon plasterboard 3
“The tests can last from one to two weeks, and it’s important to be precise and accurate – it has to be a very stable temperature,” Ms Chapman says.
As well as the temperature-controlled boxes, there is an audio testing room to determine the acoustic performance of the boards, plus a climate chamber that can be used to simulate the climate of different countries.
During CN’s visit, we see one room full of plasterboard where rain is pouring down, with cycles of heat and rain over five months simulating the cumulative effect of climate on the boards.
This was just a small glimpse of the range of R&D testing that goes on among product manufacturers the world over.
And while the final causes of the rapid spread of fire at Grenfell are yet to be officially determined, there are certainly fears over the cladding and other materials used, meaning it is vital that contractors understand how their materials will perform when used in real life – particularly when combined with other materials in a system.
The testing at Etex’s Avignon facility is just one company’s approach to this – but it shows the time and effort that can go into making fit-for-purpose materials for our construction projects, and how carefully their real-world performance is considered.