Fast and sustainable building concept

All the elements of this temporary building in the faculty courtyard in Delft were made exactly to size with an automated milling machine, so they fit together like Lego bricks. This makes it possible to construct completely error-free buildings.

The eight-meter high building is constructed of prefabricated wall and floor elements made of OSB boards with a layer of insulation between them. The exterior is finished with aluminium cladding and the windows are fitted with double glazing.

All the components, including the tongue and groove joints, were machined to 0.5 mm accuracy on an automated milling machine. This allowed for fast and accurate construction with a minimum of waste. ‘In principle, you can make any shape you like, and digital technologies also make mass customisation possible,’ explains designer Pieter Stoutjesdijk. ‘This may well lead to a revolution in the construction sector.’ The PD Test Lab building is a modular concept. Stoutjesdijk estimates that, with some practice, the building could be put up in about a week.

Thanks to the use of wood and sustainably produced OSB board, the PD Test Lab is a bio-based product. The entire facade can be reused. The aluminium cladding can be recycled and the wall and floor elements can be reused in other buildings. Some of the elements were used earlier for a pavilion at the 2017 Bouwbeurs construction industry trade fair. The overlapping roof elements click perfectly into the intermediate gutters. Together they ensure that the 60 degree roof is watertight. The substructure is constructed of waterproof chipboard. The temporary building rests on a scaffolding structure and a number of counterweights and wind bracing have been installed for stability.

The designer aimed to achieve a high level of perfection starting from the preparatory phase. All the elements were high-precision milled in various configurations. They fit so perfectly that no sealing, filler or PUR is required. In time, it is hoped that it will put an end to defect costs in the construction industry, which currently amount to some €5 billion annually in the Netherlands.

Learning factory for researchers and students

The PD Test Lab is a learning factory where students and researchers can experience the difference between practice and theory. This will help them to produce better designs.

Alongside the researchers who are leading the project, some 30 students are also helping to build the Test Lab. During the coming months, various groups of students can be found working there. Later, they will continue with follow-up research on specific products. For example, they will experiment with innovative solutions for facades, sunblinds and HVAC systems. Because the building has a modular design, it is relatively simple to make changes for specific product tests.

The product innovations that will be tested are mainly focused on digital construction, the circular economy and energy saving, explains researcher Tillmann Klein. ‘The construction sector is often accused of being conservative, but it is doing the best that it can. We want to expand the available opportunities.’ One area they are working on is the perfection of joints between structural elements. This could increase the reusability of modular elements and contribute to the circular economy.

Digitisation – 3D models, BIM, automated technologies etc – can be used to overcome a typical construction sector problem: that a building project generally involves more than one contractor. Errors are more likely to occur when several contractors have to work separately on a building. By designing elements with a computer and incorporating them in BIM models, the contractors in a partnership can communicate with each other more quickly and effectively, and potential errors can be detected in good time. In the Test Lab, students and researchers will assess to what extent the developments in digital design and detailing can be applied on the construction site.

Bringing teaching and working practice together

The PD Test Lab is a place where students of Architecture and the Built Environment can get hands-on experience and learn from their own mistakes. This is important, because the results of the designer’s work can only be tested once they have been built on site.

The PD Test Lab construction site sticks to the same working hours as any other Dutch construction site. The work starts at 7 am and the researchers and students continue to work in all weathers. This encourages them to think about changes to the working methods and the construction site conditions.

Working on a construction site also teaches them that some smart inventions do not always work in practice. For example, the poor weather during the initial stage of construction of the PD Test Lab had unpleasant consequences for the OSB wall and floor elements; the wet parts of the wood expanded, so that the tongue and groove joints no longer fitted together. Moreover, some of the boards that were delivered deviated slightly from the specified 18 mm thickness. The logistics of such a project can be considerably disrupted if your starting point is a maximum tolerance of 0.5 mm.

‘If we want to become the Tesla of the construction sector, we need to integrate engineering, design and production,’ explains researcher Marcel Bilow (Building Technology). ‘By getting practice with building ourselves, we get the feedback we need to optimise the process.’

The Product Development Test Lab will be used for at least a year. During this time, it will function as both a lab and an accommodation for 4TU BOUW. The project was start-funded with a 4TU Bouw Lighthouse grant in cooperation with TU/e and University of Twente. The costs for the project are €100,000. Half of this is for the account of 4TU, the other half has been put forward by the industrial partners displayed below.

Aldowa - FabFac - Festool - FMVG - Guardian Glass - Heco - IsoVlas - Lerobel Glass - Luning - Maasstad hout&plaat - ODS - PolyNed - Reynobond - Rojo - Rollecate - TheNewMakers - Triton - Verwij logistiek