Case Study: Low Pitched Tile Roof Repairs Using Torch-On Waterproofing

Location: KwaZulu-Natal, South Africa

Project: Waterproofing of a Low-Pitched Tile Roof Using Torch-On

Issue: Insufficient Roof Pitch for Standard Tile Underlay Waterproofing

Overview:

Target Roofing & Waterproofing was commissioned to address waterproofing issues on a low-pitched tile roof. Traditional tile roofs require a minimum pitch of 16 degrees for under-tile membranes to function effectively. However, in this case, modifications to the building structure resulted in a roof slope below the required threshold, leading to a higher risk of water ingress. A more robust and long-term waterproofing solution was necessary to protect the structure from leaks and potential damage.

Problem Diagnosis:

Upon inspection, the team identified several issues:

  • Inadequate drainage due to the shallow pitch, preventing proper water runoff.
  • Existing underlay was ineffective, leading to leaks.
  • Potential for long-term water damage if the situation was not remedied with a proper waterproofing system.

Given these factors, the best course of action was to upgrade the underlay with a high-performance, seamless waterproofing system that would enhance the roof’s durability and water resistance.

Solution Implementation:

To ensure long-lasting and reliable waterproofing, the following steps were taken:

  1. Installation of 18mm Shutter Board:
  • A sturdy shutter board was laid across the entire low-pitched roof area, creating a solid and stable base for waterproofing.
  • All joining areas were reinforced with bracing supports to maintain structural integrity.
  1. Torch-On Waterproofing Application:
  • A 4mm torch-on waterproofing membrane was applied across the surface.
  • All lap joints and cross joints were fused together using torch-on fusion, ensuring a seamless, watertight barrier.
  1. Counter Batten and Batten Installation:
  • Counter battens were placed over the trusses to allow for effective water drainage over the waterproofing system.
  • Tile battens were installed over the counter battens, ensuring that tiles could be securely fitted while reducing the risk of future leaks.
  1. Final Tile Reinstallation:
  • The roof tiles were carefully repositioned and secured to complete the restoration process.

Outcome:

  • The torch-on waterproofing system now provides a highly durable and watertight underlayment, eliminating previous leakage issues.
  • The counter batten system ensures proper water drainage, reducing the risk of pooling and moisture buildup.
  • The reinforced structure with shutter board and bracing enhances the stability and longevity of the roof.

The project comes with a 10-year guarantee, although the system is expected to last significantly longer with proper maintenance.