Janapriya Residential Complex Terrace

Project Overview

Scale: 38,000 sq ft across the rooftop terrace and external sidewalls of a multi-block residential complex by Janapriya Engineers Syndicate in Hyderabad.

The project brief required a durable waterproofing system across both flat terrace areas and vertical external walls, including parapet detailing and window-sill junctions — points where water ingress is most commonly reported in handed-over residential buildings.

Victoria Waterproofing was engaged after a site review and system specification discussion with the developer's site engineer. Method selected: torch-on SBS bituminous membrane on flat terrace areas, polyurethane elastomeric coating on exposed vertical surfaces.

Handover: August 2023. Two monsoon cycles without a single leak complaint as of December 2024.

Substrate Condition at Intake

The terrace slabs were in good structural condition but showed the typical issues of a construction-phase surface: form-oil contamination at several bays, shrinkage cracking at slab edges, and inadequate drainage falls at two roof outlets.

External wall surfaces presented variable substrate quality — areas of honeycombing at column-to-slab junctions, prior paint coatings of unknown adhesion, and two locations with active damp patches from internal sources. These were identified during a pre-application survey and addressed before waterproofing coats were applied.

Method Selection Rationale

The torch-on SBS system was selected for the flat terrace areas for two reasons. First, the developer's specification required a system with a documented service life of 15 years minimum, which SBS modified bitumen meets and polyurethane coatings do not always achieve under Hyderabad UV and thermal cycling conditions. Second, the terrace was to remain accessible for maintenance — the two-layer torch-on system with a mineral-surface cap sheet provides abrasion resistance for foot traffic.

Polyurethane elastomeric coating was selected for the vertical external walls because it bridges hairline cracks dynamically, accommodates structural movement, and applies uniformly to irregular masonry surfaces without the detailing complexity that a membrane system would require.

Execution Highlights

Parapet detailing was executed with SBS membrane carried over the parapet cap and turned down 200mm on the external face. This continuous treatment prevents water entry at the most common failure point on residential terraces — the junction between horizontal membrane and vertical parapet wall.

Window-sill and window-frame junctions on external walls were treated with polyurethane sealant prior to elastomeric coating application. All sealant work was inspected before the main coating sequence began.

Drainage outlets were re-grated and sumps lowered at three locations. Fall correction was carried out at two bays where the original concrete finish had created flat spots.

Post-Handover

The 5-year written warranty was issued covering both the flat terrace membrane and the vertical polyurethane coating system. Post-monsoon inspection confirmed no active leaks across the complex. The building management team has not reported any warranty issues to date.

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Site inspection and technical specification by Subhash Chander, Victoria Waterproofing.