Resealing Expansion Joints at Meadowhall Centre in the U.K.
In spite of all of its design and engineering awards, Meadowhall Centre had a problem. Over a decade of traffic had exposed the reality that the Suffix complex's parking structure was leaking. Unfortunately, this situation was not unique. Car parks all over the world are leaking every day primarily due to the use of the outdated sealing technology inherent to extruded rubber sealing glands which are failing to meet the performance standards necessary to seal the gaps and keep structures watertight. Fortunately, this common problem has an available solution in the form of precompressed coated-foam sealants.
We understand that movement joints in car parks and other structures are necessary to handle thermal and structural expansion shifts. The most modern of today's movement joints allow for increased performance while greatly reducing installation time. Expansion joints (also known as movement joints) have advanced beyond compression seals and are now available as feature-rich precompressed coated-foam expansion joints. These watertight primary seals fit the conditions of today's new and refurbished car parks by being traffic-durable, adaptable to varying structural conditions and are much simpler and quicker to install.
It needs to be watertight
The primary performance failure of many earlier expansion joint designs is the inability to remain watertight. Given the reality of rain or snow at anytime, water leaks and drainage are a constant test of the movement joint's ability to maintain a seal based on expansion, material degradation or product composition. A movement joint is as good as its weakest link, or in this case anywhere that it allows moisture to pass through a sealed surface. EMSEAL, which has had great success throughout the UK with its coated foam DSM System, points to the basic tenant of providing a movement joint that is "Watertight by Design."Â
The DSM System product line combines a factory-applied and cured silicone bellows with a microsphere-modified acrylic-impregnated expanding foam sealant backing. These coated-foam products are an infused cellular foam material coated with a high-grade trafficable silicone coating tested for durability under continuous UV, water, and air pressure differential exposures typically experienced in car parks and larger structures. Continuity of seal and continuity of thermal insulation throughout changes in plane and direction are hallmarks of the DSM System. In addition, the products' ability to maintain watertightness while handling curves and directional changes further sets it apart from extruded rubber seals.
Ease of Installation
Additional significant advantages to precompressed coated-foam movement joints are the non-destructive nature of their installation and also the quickness with which they can be installed. Because the joint is held in place by the backpressure of the foam there is no need to anchor or to hold the joint in place by inserting any fasteners into the substrate walls or surface blockouts. The integrity of the substrates is never compromised. Back-pressure maintains the seal and ensures that the silicone bellows is never under tension from the effects of joint movement. The backpressure also allows for the necessary continuous expansion and contraction of the joint avoiding the constrictive problem of compression-set common to extruded rubber seals. And the pliant nature of the foam structure adapts well to inconsistencies in the substrate conditions.
Peter Cowlard, Technical Director at Makers Construction Limited, recently spoke of their experience with precompressed coated foam movement joints on the Meadowhall Centre car park refurbishment project. "The structures have expansion joints in them and the finished waterproofing is asphalt," he says.
"The original joints were renewed about eight years ago and they have subsequently failed. These were a compression-type joint, which was glued in place using proprietary system and a nosing of polyurethane. They all subsequently failed. The client was looking to renew all the joints and looked around the marketplace for a suitable jointing system."
"Looking round the world some 15 years ago we came across EMSEAL, and it fits a bill with us as a contractor in that we can rely on the product and our name at the end of the day is attached to it. We find it easy to install and it's getting good acceptance from our client base. Within the range of EMSEAL joints, there's something that fits nearly every application we come across. The ease of application is a real boon."
Makers approached Meadowhall with the EMSEAL system and, after assessment and investigation, the EMSEAL system was adopted for the works. Makers is now installing metres of the DSM joint to the centre's car parks, meaning the shopping centre's car parks will no longer leak.
For more information about EMSEAL's innovative and expanding product lines, please contact EMSEAL at techinfo@emseal.com or call 508-836-0280 or visit the EMSEAL corporate website at www.emseal.com.
