SIKA WATERTIGHT SOLUTIONS ENSUREFor a £117 million shopping centre in Newport, a comprehensive range of waterproofing solutions from Sika has provided unrivalled waterproofing protection ensuring this major retail development is watertight and remains on track for completion.

The Friars Walk Shopping Centre in Newport, built by Bowmer and Kirkland Limited for Queensberry Real Estate, offers more than 390,000 sq ft of retail and leisure space which includes a 90,000 sq ft Debenhams Department Store, an 8 screen Cineworld cinema, a range of shops including Next, Top Shop and River Island, along with 12 family restaurants and a new 350 space modern car park and bus station.

For the expansive lower area of the building, engineers Waterman Consultants required a robust and durable waterproofing solution that could meet both Grade 3 of BS 8102:2009 and BS 8485 codes whilst at the same time being flexible for the different site details.

To meet the requirements, the specification included a dual system of more than 9,000m2 of the Sikaproof A08 system, a totally new concept in membrane barrier design, together with 3,300m3 of Sika Watertight Concrete to deliver outstanding levels of watertightness to the lower floor.

The membrane surface of SikaProof A is embossed with a grid pattern, which contains a sealant, and is topped by a thin layer of fleece which forms a mechanical bond to the concrete when it dries. The grid pattern is also unique. It offers additional protection, due to the integrated sealant, which bonds tightly with the surface of the concrete, forming mini watertight compartments.

Therefore, even if the membrane is damaged or pierced, moisture or pressured water cannot spread between the membrane and the concrete structure as it is contained within the small damaged grid square.

Sika Watertight Concrete, which was supplied by Lafarge Tarmac to Churngold Construction, is a high quality solution for below ground and basement construction that prevents water from migrating through the concrete. State-of-the-art Sika admixtures work within the concrete, firstly to reduce the water/cement ratio, thus increasing the density of the mix and minimising the size, volume and continuity of the concrete’s pores, and secondly, fill the remaining pores.

James Rivers, Churngold Construction commented: “These are great waterproofing systems which were sold very well to the design team through an outstanding technical detailing ability. I cannot speak highly enough of the team at Sika.”

To complete the system, construction joints were sealed with the SikaSwell jointing system, which consists of joint sealing profiles that expand on contact with water to seal any voids between adjoining concrete slabs.

The Sika Watertight Concrete system complies with BS 8102:2009 Grade 3 for habitable areas where no water penetration is acceptable, an essential consideration for the basement area. The system also complies with BS 8485 which ensures the membranes, including the joints, restrict the ingress of hazardous ground gases into the building.

With Sika’s comprehensive waterproofing system in place, this successful application has led to the engineers specifying the Sikaproof system on another major retail development in the heart of Oxford city centre which is a totally new concept in membrane barrier design due for completion in 2017.