Commercial Object Bečmen – Waterproofing of Roof Skylights Using “Sikalastic 641”

Following the request of the investor’s representative, a site inspection of the roof was carried out, focusing on several glass skylights integrated into the roof panel system. During the inspection, the investor reported recurring water ingress at the skylight–roof panel interfaces.

Existing Conditions

A detailed assessment confirmed that the original sealants at the junctions between the roof panels and the skylights had significantly deteriorated over time, resulting in active leakage.

Below is the condition of the skylights prior to intervention:

Proposed Solution – Sikalastic 641

The recommended solution was the application of Sikalastic 641, a one-component polyurethane liquid-applied membrane.

Why This System

This membrane provides long-lasting waterproofing even in complex scenarios, such as:

• remediation of aged and failing joints between various roof components (sheet metal flashings, HVAC units, roof panels, penetrations, etc.)
• waterproofing of irregular shapes
• sealing transitions between different materials
• waterproofing of difficult-to-access roof details where conventional sheet membranes cannot be installed

More information is available in the related publication:
Waterproofing with the liquid membrane “Sikalastic 641”

Reference Projects – Similar Works

Examples of projects involving waterproofing of individual roof details, penetrations, hard-to-access joints, and full roof areas include:

• Office Building – Nova Pazova
• Auto Service Facility – Zemun
• Coca-Cola Zemun – Roof Penetration Waterproofing
• Office Building – Dobanovci
• West Tower – Belgrade
• Coca-Cola – Skylight Waterproofing
• Agrounik – Šimanovci
• Medius – Nova Pazova
• Residential Building – Belgrade
• Commercial Facility – Borča
• Residential Building – Surduk
• Metro Horeca Center – Parapet Waterproofing
• DRÄXLMAIER – Waterproofing Maintenance
• Commercial Facility – Šabac
• METRO Horeca – Terrace Repair
• Roof Terrace Rehabilitation – Liquid Membrane
• Medius Plus – Stara Pazova
• DDOR Novi Sad – Headquarters
  …and many other successfully completed projects.

Execution Methodology

Substrate Preparation

Before applying the membrane, the following steps were performed:

• thorough cleaning of all surfaces
• removal of loose or deteriorated material
• application of the appropriate primer

Substrate preparation and primer application:

Membrane Application

After the primer cured, two reinforced coats of Sikalastic 641 were applied, incorporating Sikalastic Reemat Premium as reinforcement.

Finished appearance of the skylights after the works:

Performance

This waterproofing system provides:

• reliable elimination of leakage
• long-term durability
• optimal performance when applied according to manufacturer specifications