Flexseal Flanges Are Going To The Zoo

By Admin


12th Nov 2015

Puddle flanges from the UK’s leading coupling manufacturer, Flexseal, have played their part in the engineering solution in the expansion of world-class attraction, Islands at Chester Zoo.  Crown House Technologies Limited, the services arm of the project’s contractor Laing O’Rourke, first specified the puddle flanges within the ventilation system for the Indonesian jungle house - the centrepiece of the project, Monsoon Forest.  They were so impressed that they further specified the same product within the water system of the new animal pools.

Chester Zoo is home to over 12,500 animals from more than 400 species, as well as housing exotic plants from across the globe.  The new attraction, dubbed Islands, features six different South East Asian island habitats and has added the equivalent of 7 full-size football pitches to the zoo’s area, at a cost of £40m.   It features a 450 metre river, along which visitors will be able to take a boat ride – a first for a UK animal attraction.   

Crown House Technologies Limited were commissioned to construct a complex technical package across the new area, including irrigation pipework, venting ducts, borehole water supply and treated water piping. 

The Indonesian jungle house, Monsoon Forest, at 100m x 40m, is now the UK’s largest ever indoor zoo exhibit, housing Sumatran orangutans, Sulawesi crested macaques and Sunda gharial crocodiles in an indoor subtropical rainforest.  “It’s vital that the temperature and humidity levels within the jungle house remain within tight tolerances, to provide the right atmosphere for both the animals and the plants which form their habitat” explained Philip Ashton, Project Manager for Crown House Technologies Ltd.

The ventilation system consists of a 2.5m x 2m concrete duct which encircles the building.  Large spigots act as chimneys and extend from the main duct into outlets in the animal enclosures.  The air is extracted through vertical concrete shafts, treated in a plant room and recirculated. Each spigot consists of a single piece, especially constructed by external mains specialists Sant’s Fabrications to direct the air flow correctly.  They are then installed into a pre-fabricated hole in the concrete duct and encased in concrete.  Flexseal’s puddle flanges form the seal where the spigot meets the main duct.

“To keep total control over the system, we needed to create a water and airtight seal,” continued Philip.  “Sant’s Fabrications could have bespoke fabricated each one, but with over 30 puddle flanges within the ducting, this would have been costly and time consuming.”  Instead, Crown House Technologies discussed the project with contacts from Fusion Provida, their chosen merchant, to find an off-the-shelf solution.  Flexseal provided samples of its puddle flange, so that Sant’s could prove the fabrications would work and they could be tested by Crown House before specification.

William Sant, Owner of Sant’s Fabrications, commented, “We found it was easy to incorporate the Flexseal flanges into the fabricated piece and we’re convinced that they offer the best seal possible.  Using the Flexseal puddle flange also made our part of the job quicker, ensuring the products were on site swiftly and there was no risk of hold ups with construction for Laing O’Rourke.”

“The air ducting system was an early challenge within this project.  We then moved on to construction of the pools for the Sumatran tigers, giant Asian forest turtles and Sunda gharial crocodiles.  These pools form part of the diverse habitat for these animals” stated Philip.  “The benefits of the puddle flanges for this part of the project were clear.  Along with Sant’s Fabrications, we introduced the product to Nautilus, the specialist contractors for this area, who are worldwide experts in zoo water enclosures.”

The water system for the pools included skimmer pipes to top up the pools and sumps to take the detritus away.  The puddle flanges required for these applications were of a smaller bore to those used on the ducting system.  Moreover, the same airtight and watertight quality was required, from a cost-effective, readily-available product.

“I’ve over 30 years’ experience in this type of work, constructing many venting and chimney systems,” said Philip.  “This project meant thinking slightly differently.  For example, instead of sealing the system for fire and noise reasons, we had to be sure the seals would prevent insects such as cockroaches from entering the ducts.  Thinking differently has led to using different products, but now that we’ve been introduced to the Flexseal puddle flanges, I believe that there will be other instances where they are useful in cast solutions.”

For more information on pipe connection solutions, please see or call Flexseal at 01226 340888.

Tags on this post: ventilation