KHIA ID: 4689
Industry: Buildings & Structures (BSTR)
Application: RPA-Roof Problem Areas (RPA)
Substrate: Asphalt and concrete
Customer Location: College, Cambridge, UK
Application Date: August 2013

Belzona® 4131 (Magma Screed)

Belzona® 3131 WG Membrane)

Belzona® 9231 (Surefoot Aggregate)

Problem: The asphalt roof was leaking underneath the concrete slabs, causing water damage to the rooms below. To repair the roof the College was planning to remove the concrete slabs, replace the asphalt roof and then reinstall the concrete slabs.
Photograph Descriptions
  1. Leaking balcony roof with paving slabs
  2. Close up of paving slab edge
  3. Gaps between  slabs filled with Belzona® 4131
  4. Balcony roof coated with Belzona® 3131 system with 3rd coat incorporating Belzona® 9231 aggregate anti-slip system
Application Situation
An asphalt balcony, used as a walkway, covered with concrete slabs.
Application Method
Application was carried out in accordance with Belzona Know-How System Leaflet RPA-6. The gaps between all paving slabs were cleaned and filled with Belzona 4131. A fully reinforced Belzona® 3131 system was then applied to weatherproof the area. This was followed by a further coat of Belzona® 3131 blinded with Belzona 9231 aggregate to create a non-slip walkway.
Belzona Facts
To replace the leaking asphalt roof with new asphalt was expensive, would expose the building to the weather and would take over one week. The Belzona system meant the existing roof substrate stayed intact, the roof coating was completed in 3 days and new Belzona non-slip surface provided additional safety.