Completed in 2017, AMR Mazda underwent significant redevelopment of their well-established dealership in Stanmore. At AMR Mazda they are committed to providing Superior Service and Quality to all their customers. This was reflective in their choice of contractor. BMH Constructions was awarded the prestigious project in conjunction with their preferred concrete supplier Holcim. Discussions started on the critical roof slab detail. Enhanced compressive strength, resistance to chemical attack, reductions in chloride penetration and carbonation, prevention of sulfate attacks and the capability to self-heal cracks up to 0.5mm were all essential requirements from the client.

Penetron Admix was chosen as a stand-alone system to provide waterproofing and durability to the roof slab of the structure. Also utilized as a customer and employee carpark. A critical element as the offices and showroom underneath required maximum protection.

On the day of the pour, high heat, strong winds and unforeseen mechanical issues at the batching plant meant that the construction team were set for a range of challenges. Premature moisture loss, cold joints and plastic shrinkage cracking were all bound to cause issues to the slab. As a result, there were many performance highlights that Penetron Admix and its crystalline technology had to demonstrate. As the supporting photos show, the slab did crack. However, the majority self healed following the chemical reaction of the Penetron Admix and the introduction of secondary water.

Several months later, there were 3 persistent cracks that required extra attention. These cracks were border-line on the 0.5mm limit of the Penetron Admix. A recommendation was made that a coating of Penetron crystalline slurry would be worked vigorously in to the crack and then water cured. This in-turn sealed these cracks with no further issues on site.

Client: AMR Mazda
BMH Constructions
Concrete Supplier: Holcim

Areas Treated: Roof slab car park

Products Used