Flat Roof Waterproofing and Renovation with ONE® System

A flat roof located on Allen Street in the Lower East Side of New York City showed clear signs of deterioration and loss of waterproofing performance.

The existing smooth torch-down bituminous membrane required restoration — but without demolition, open flames, or complex logistics.

The property owner needed a solution that was:

• Fast to apply
• Safe for contractors
• Logistically simple
• Free from open flames
• Sustainable and low impact

The solution: the ONE® waterproofing system by Winkler.

Project Context and Requirements

The building featured a flat roof finished with a traditional torch-applied bituminous membrane that had deteriorated over time.

The owners required a system that would:

• Restore the roof’s waterproof integrity
• Extend the life of the existing membrane
• Avoid costly demolition and disposal
• Comply with strict NYC safety regulations
• Reduce onsite material handling in a dense urban environment

Given the constraints typical of Lower Manhattan —limited accessibility, stringent safety rules, and the need to minimize disruptions — traditional hot-applied systems were not suitable for this project.

Challenges of the Existing Roof

The inspection revealed:

• Widespread membrane deterioration
• Cracks and localized ponding 
• Increasing risk of water infiltration
• The need to avoid expensive tear-off work

Additional constraints included:

• Compliance with New York City fire and safety codes
• Difficulty transporting bulky rolls and propane cylinders
• A strong need to reduce construction time and environmental impact

Objective: Restore waterproofing performance while minimizing time, cost, and waste.

The Winkler ONE® Solution

ONE® is a next-generation liquid waterproofing membrane developed after seven years of intensive research. It is a single-component, water-based system designed specifically for renovating existing roofs without removing the current.

Key Features

• Direct application over existing bituminous membranes
• Supplied in practical 20 kg buckets for easy transport
• No open flames, no propane gas, no separate primer 
• Works on damp, very damp, and even wet substrates
• Application temperature: 0°C to +45°C
• Rainproof in just 2 hours at 20°C
• Breathable yet resistant to negative water pressure up to 4 atmospheres
• Exceptional puncture and abrasion resistance

This system creates a continuous, seamless waterproof layer, eliminating the need for demolition or membrane disposal.

Operational Benefits

• Seamless finish with strong substrate adhesion
• Faster drying and shorter application time
• Safe, emission-free work environment
• Simplified logistics ideal for urban projects

Technical and Environmental Advantages

ONE® offers several advantages over traditional membranes:

• Cold-applied — no flames, no fire hazards
• Reduced labour and installation time
• Excellent adhesion to aged bituminous surfaces
• Water-based formulation aligned with WinklerSafe standards
• High elasticity and UV resistance
• Minimal waste and reduced environmental footprint

ONE® not only enhances performance but also eliminates risks associated with torch-applied roofing systems.

Results Achieved

The completed project delivered a roof that is:

• Fully waterproof and long-lasting
• Safe to install with zero flame exposure
• Lightweight and compatible with the existing structure
• Low maintenance
• A clean, durable surface integrated seamlessly into the NYC’s urban environment

This case demonstrates how ONE® make roof renovation faster, safer, and more sustainable- especially where traditional systems pose logistical or regulatory challenges.

FAQ – Frequently Asked Questions

Why choose ONE® instead of a traditional membrane?

ONE® is cold-applied, requires no open flame, reduces waste, simplifies logistics, and eliminates costly tear-off operations.

Can ONE® be applied over existing bituminous membranes?

Yes. It is specifically formulated for direct application on existing roofing systems.

How long does the installation take?

Because ONE® dries quickly and becomes rain-resistance 2 hours (at 20°C), projects can be completed much faster than with conventional systems.

What are the environmental benefits of ONE®?

The water-based, solvent-free formulation reduces emissions, eliminates gas cylinders, and minimizes waste.