Promat contributes to the fire protection of timber high-rise residential building at Amstel waterfront.
As architects and engineers look for new ways to support the ambitions of the European Green Deal, they increasingly discover the potential of Cross-Laminated Timber (CLT). The Dutch real astate developer Lingotto, together with architectural office Team V and engineers from Arup, designed HAUT, a 73-meter high residential building in Amsterdam that prefers wood instead of traditional concrete walls and floors. Promat helped the design team and contractor to protect this landmark of sustainability against fire.
Wood is increasingly considered the magical building material of the future. While traditional building materials become scarce, trees can be replanted indefinitely and have a unique quality: they are able to absorb and stock high amounts of CO2 from the atmosphere. And that is exactly what we need to combat climate change. No wonder that progressive architects and engineers explore how they can integrate more Cross-Laminated Timber (CLT) into their innovative designs.
When Lingotto and the architects of Team V and engineers from Arup won the design competition for the City of Amsterdam to develop the new high-rise residential building HAUT along the waterfront of the Amstel in Amsterdam, they decided to make this an example of sustainable innovation. Inside the building they used load bearing CLT walls and CLT floors with a concrete topping. This will not only dramatically reduce the ecological footprint of the building, it also creates this unique feeling of well-being and comfort, associated with timber interiors.
A fire-safe design
A the question remains: how can you protect such a large-scale building and its inhabitants in case of fire? The engineers from ARUP designed a robust building that accounted for the increased fire load due to exposed timber, and also needed to address the risk that the timber walls of the building would potentially ignite each other, creating extended and unpredictable fire scenarios. This called for a clever multidisciplinary design approach and fire safety measures. Existing legislation in the Netherlands requires that, depending on the height and use of the building, main load-bearing structures be fire-resistant for up to 120 minutes and fire compartments for 60 minutes. As part of the overall fire strategy the building has multiple fire safety measures including a low-pressure water mist system throughout. Arup's fire engineers designed the building to account for fire scenarios which extended the duration of a fire due to the exposed CLT. This meant that the CLT walls needed to not significantly contribute to a fire in the compartment and would therefore need to be protected for longer than 60 minutes. Arup analysis resulted in a requirement for the CLT walls to not significantly contribute to the fire load in the fire compartment for at least 90 minutes. Although there are different ways to achieve this fire resistance, the best multidisciplinary solution for HAUT was to protect the CLT from charring for 90 minutes by covering it with a fire-resistant board.
A tested solution
When the design team and contractor looked for a partner to find feasible fire protection options that would comply with the design specifications for such an innovative project, the project managers also called upon the fire protection experts of Promat. Our fire safety engineers initially used a performance-based method to demonstrate that the Promat products would protect the CLT walls in the building for at least 90 minutes, making sure the timber walls would not exceed temperatures of 270°C. The products proposed by the Fire Safety Engineering team of Promat prescribed 2 layers of 12 mm PROMATECT®-100, mounted on a 50 mm metal C- and U-frame, filled with 40 mm (30 kg/m³) of mineral wool as a protective layer, which would fit the design teams specifications and clients ambitions.
A fire test was then carried out at the Promat Fire Lab which demonstrated how the proposed solution would perform. A CLT partition wall was tested for 90 minutes and was compared to a traditional plasterboard solution. When both panels were removed from the furnace, the difference in fire resistance was quite spectacular. While the plasterboard panel had burned away and the CLT wall was fully involved in flames, the PROMATECT®-100 panel was still in place and continued to protect the CLT wall from the fire without charring of the CLT.
“Promat has proactively used its product knowledge, experience and test facilities to provide innovative products and solutions for this spectacular building and demonstrated to meet the stringent Arup fire and acoustic requirements which can be built efficiently”.
Pascal Steenbakkers, ARUP Engineering
An efficient installation
A solution for passive fire protection should not only offer ultimate performance in case of fire, it should also be practical and offer an affordable solution for the building contractor. Therefore, the Promat team also visited the main contractor to demonstrate and discuss how the boards could be installed with the correct product specifications and with ease. During this training session, new demands arose. Would the board also be suitable as a protective layer in bathrooms? A uniform approach with only one type of board would save time for the contractor and offer extra protection to the building. Another test was done, which showed that the Promat board is also fit for wet environments like bathrooms and can be used as a basis for tiling. Combined with fire stopping products PROMASEAL®-AG and PROMASEAL®-A, the bathrooms and apartments now become firesafe compartments that are to contain the design fire scenarios and prevent the fire from spreading through the building.
"This was the first project in The Netherlands of this kind with Cross-Laminated Timber (CLT) and it presented a number of challenges with regards to structural fire safety. With the products of Promat, solutions were quickly presented and executed guaranteeing the integrity of the building structure and installation components throughout this stunning high-rise tower in Amsterdam."
David Hinterberger, Novio Firestop B.V.
In the meantime, the construction process in the building is on schedule and 10.000 m² of 12mm PROMATECT®-100 boards are being fitted into the HAUT building. This successful shared solution, found by experts, not only shows the eagerness of Promat to assist architects, engineers and contractors to develop sustainable building solutions. It also shows the need for a close partnership and coordination between designers, builders, contractors, and installers to come up with a firesafe solution that can be installed in time, within a fixed budget.
The project HAUT is a collaboration between Real Estate manager Lingotto, Team V Architectuur, ARUP fire and multidisciplinary engineering and main contractor: J.P. van Eesteren.
For more information on the installer of the PROMATECT®-100 partitions: AT Projecten and installer of the fire stopping solutions: Novio firestop.
