Technology of Flexible Roof Repair
Roofing is one of the most beautiful, yet delicate elements of any building, constantly requiring supervision and care. Regardless of the season, each brings potential load and possible risks to the roofing system. No matter the type or purpose of the structure, every design has its weak point.
In this article, we will discuss proper operation and maintenance of flexible roofing and describe the repair technology for the waterproofing membrane.
Materials for Flexible Roof Repair
The primary material used for full or partial reconstruction of flexible roll roofing is a bituminous self-adhesive membrane made from SBS-modified polymers. The installation method on horizontal surfaces is adhesive bonding. When heated with a propane torch at approximately 600°C, the polymer softens and develops excellent adhesion to the substrate. After cooling, the membrane becomes firmly bonded to the floor slab or existing roof.
The main requirement for working with self-adhesive materials is a positive ambient temperature, as most bituminous membranes can only be applied under such conditions.
On certain substrates, a bituminous primer must be applied before installing the waterproofing layer to enhance adhesion. This thick, cream-like liquid can be applied using a roller or brush.
Common Problems with Flexible Roofs
The best repair is one made in time. It's easier to fix minor flaws and damages to the roofing membrane than to dismantle half the roof in search of leaks. To accurately assess the scope of repair work, periodic inspections of the roof surface should be conducted to identify common defects for a specific building type.
The vulnerable areas susceptible to membrane degradation vary depending on the building’s function.
- Residential multi-story buildings.
Residents of high-rise buildings often use the roof for installing antennas, while upper-floor occupants also use it for air conditioning and ventilation systems. Roof areas contain access points to elevator shafts, serviced sections of flues, plumbing systems, etc. As a result, maintenance staff and municipal workers frequently access the roof, especially during winter to clear snow and ice.
Unfortunately, none of these visitors to flat roofs typically consider the integrity of the waterproofing membrane. During inspections, special attention should be paid to the condition of parapets, vertical membrane terminations, areas around newly installed equipment, walkways used by maintenance personnel, and similar zones.
These areas must be checked for damage and cracks where moisture can enter, freeze, and cause further degradation of the waterproofing layer, potentially leading to through-freezing of the roof.
During roof reconstruction, it’s advisable to install special footings or platforms under heavy structures (e.g., advertising panels) and reinforce vertical sections with additional layers of waterproofing material.
- Industrial facilities.
The main challenge with industrial buildings (warehouses, factories) is the absence or improper use of drainage systems (stormwater drainage) on the roof. Due to poor or nonexistent water runoff, ice accumulates during autumn and spring, which is often removed mechanically, causing irreversible damage to the waterproofing material.
On such roofs, full waterproofing reconstruction is typically performed by laying a new layer of bituminous material over the old, damaged one. A second key factor in ensuring long-term performance without repairs is timely staff training on permitted actions on the bituminous membrane surface for personnel working on the roof.
Seasonal Challenges in Flexible Roof Waterproofing
During spring, inspect the roofing surface for air bubbles, the quality of joints between adjacent sheets, and the watertightness of deflector and downspout seals in the stormwater drainage system.
During summer heat, pay close attention to micro-crack formation due to high-temperature bitumen heating. The material must be evenly distributed across the roof and parapets, without localized stress points that could lead to membrane cracking.
In autumn, ensure gutters and downspouts are clear of fallen leaves. The best solution is to install special filters on deflectors and water inlets.
During winter, if the parapet height allows, clear snow from the roof promptly but leave a 2–4 cm snow layer to avoid damaging the membrane with shovels or scrapers. This residual layer won't create significant load.
