Broadway Plaza is a mixed-use development in Birmingham City centre, housing an array of eateries, leisure facilities and accommodation. The site encompasses the listed Old Birmingham Children’s hospital which in turn provided waterproofing challenges.
The Plaza had suffered severe water ingress through the main deck. IKO highlighted the poor condition of the existing waterproofing system to the main plaza, walkways, balconies and car park. Established and quantified saturation of the deck and the existing waterproofing system had failed due to non-dressed abutments, bonded to the substrate or bonded to the laps.
The scale of the work required a phased approach since the site needed to remain open to emergency vehicles, which also meant finished project needed to handle point loading and the compressive weight of the vehicles.
Water ingress had caused fire retardant paint to peel from the metal structure in the car park, some rust to the metal structure and ad hoc guttering had been added to divert water from within some of the accommodation blocks. Insufficient drainage was noted during large downpours and corrosion was visible to door thresholds of some of the outlets.
Solution and Installation
The existing waterproofing system was stripped to the concrete substrate and new drainage channels were introduced with falls directing water to the new high level drainage. IKO Permascreed was introduced as a temporary waterproofing solution. This provided the falls that were required with the previous screed being too wet to use. IKO Permascreed also provided a protective layer against gases rising from this screed that may have affected the additional liquid waterproofing system.
IKO Polimar FCS (Fast Curing System) Waterproofing System was introduced across the plaza terminating to brickwork, stanchions, lights and door thresholds. Exposed areas were treated with IKO FCS Balcony and Walkway System preserving the system while taking foot traffic. IKO Polimar FCS provided a feature on these details as well as a practical solution where construction provided a challenge.
The upper level of the car park’s cracks and fistulas were treated to elevate further degrading. IKO Polimar Fillers and Levelling Mortar were installed to take deflections from the surface. IKO Polimar FCS Walkway System was then applied.
Escalators were removed and staircases installed with an IKO Polimar FCS finish. Damaged kerbs, gutters, expansion joints or deck/substrate’s were correctly fixed to ensure satisfactory installation of the new waterproofing system.
A number of trees had to be removed as their roots were penetrating the waterproofing and this area was waterproofed with IKO Polimar FCS, then backfilled using IKO enertherm XPS insulation board to raise the areas to the desired level followed by a geotextile membrane, coarse and fine aggregate, completed with the final paving.
The project was delivered on time and on budget, with the FCS provided in ICB containers to reduce site waste.