Wavin Case Study I Hypérion Tower – Bordeaux, France - photo credit JP Viguier

The first wooden living tower in the country – a stellar example of creating climate-resilient cities

Have you ever heard of a wooden tower? This is the challenge embarked on by Eiffage Construction with the launch of the Hypérion Tower in Bordeaux (France). Borrowing its name from the largest tree in the world – the California redwood tree – the Hyperion wood frame tower is fitted with the new Wavin Tigris M5 press fittings and multilayer pipes.
Across Europe, contractors and pipeline installers are making the switch from water pressure to air pressure testing. Traditionally, pipelines are pressure tested by using water. But, as we strive to make our building spaces more sustainable and resilient, we seek more forward-thinking alternatives like air pressure testing – which can be a more secure pressure testing method, reducing the risk of both Legionella and water damage. 

First of its kind – made in France

As part of an urban renewal program in the heart of the city, near the Saint-Jean train station in Bordeaux, the players in this project took on the challenge of building the tallest wooden residential tower in France, more than 50 meters in height. In order to guarantee the wind and seismic stability of the structure, the foundation of the tower and the first three levels are constructed of concrete. This "backbone" is comprised of wooden framed walls from the forests of Corrèze.  Environmentally, wood is a bio-based and recyclable/renewable material which has the advantage of storing CO2 even after cutting, and of warding off the greenhouse effect. This year-long project is part of a low carbon footprint construction concept.

The Challenge: Water damage is a risk factor for wooden structures

And because of this, the structures are subject to the ravages of humidity. Furthermore, there is the health risk of Legionella. If pipes are not dried properly after water-pressure testing, Legionella bacteria can grow.

When you pressure test with air, you can skip the time-consuming drying phase, but also be 100% assured that no Legionella bacteria have been introduced to the pipes during construction.”
Don Elworthy , Senior Contracts Manager, Panks Engineers Ltd. (UK)

The Solution: Acoustic leak detection

The acoustic leak detection system is integral to the Wavin Tigris M5 and was decisive in the choice of this solution in order to limit any risk of water damage due to leakages. Wavin’s “Acoustic Leak Alert” (rather than the standard water leak alert) allows installers to detect any leaks caused by loose fittings on an entire system. With Wavin’s Tigris M5, any uncrimped fitting will make a hissing sound of up to 80dB – making it easier to locate the source of the leak. The Tigris M5 is the first – and only – fitting to be equipped with such a leak detection system.

The first part of the order, 5,000 meters of multi-layer pipes and the 840 Wavin Tigris M5 16-diameter fittings, supply the hot water/sanitary cold-water networks of the future housing units in the Hypérion Tower. Without welding or risk of corrosion, the sealing of these systems is safely ensured – guaranteeing reliable and durable connections, thanks to the robust design of the Wavin fittings. Additionally, the “Multi Jaw” functionality of the Tigris M5 fitting allows for greater flexibility in crimping tools (U, Up, H, TH and B compatible). It is in this context that Wavin, in collaboration with the various players, implemented the Wavin Tigris M5 solution within this innovative project.


The value of air pressure testing

Water damage is the second most frequent cause of loss during building projects. Pressure testing with air means you can be 100% sure that leaks won’t destroy electrical installations, new flooring or fresh drywall. Air pressure testing is done incrementally. Each air pressure test takes minimum of 130 minutes, compared to only 20 minutes for each water test. However, when you add the preparation time of a water test (the time it takes to get all air out of the system) and the fact that the whole installation needs to be flushed once per week, water testing is ultimately more unwieldy and time-consuming.

When testing with air, the pressure test is no longer a hiccup in the building installation phase. Leakage testing with air has several advantages such as: no risk of bacterial growth (Legionella) in the period between testing and using due to water stagnation. No messy work space and no more need for using dirty sprays. It’s quick, clean and safe as it already works at 0,15 bar, making it a perfect solution to check prefabricated installations. And the pressure test can also be executed during winter time – without the risk of freezing your pipes. Furthermore, there is no longer a dependency on early water supplies at the building site. A simple air compressor will do the job.”
Ruurd van Leeuwen , European Product Manager (Hot & Cold), Wavin

Building healthy, sustainable environments

The Hypérion Tower is designed to save 14.7 tons of carbon emissions per apartment – an epic step towards achieving a clean energy environment. For Wavin, it’s been a privilege to be a contributing force to such an impactful, sustainable building project. The Hypérion Tower is scheduled to be completed by May 2021.

Interested to learn more about the Tigris K5/M5 system, click here.

Project: Hypérion Tower – with housing units, shops, offices, parking
Location: Saint Jean-Belcier area, Bordeaux, France
Built area: 17.000 m²
Wooden tower: 7.000 m² / 98 housing units
Lower housing building: 5.760 m² / 78 housing units
Office building: 3.900 m²