Flat roofs in Cork face a unique set of stressors.
From the relentless Atlantic humidity to the "freeze-thaw" cycles of the Lee Valley, traditional flat roofs often fail because they weren't designed for 21st-century rainfall.
Most "leaks" aren't just holes in the felt; they are symptoms of structural sagging, poor ventilation, or degraded seams.
At Hallmark Roofing, Patrick O’Sullivan and his team specialize in engineered flat roof solutions.
We don't just "patch" a leak; we identify the root cause—whether it’s ponding water, interstitial condensation, or thermal cracking—and provide a permanent, guaranteed fix.
Call (021) 202 1045 for a Free Flat Roof Assessment
To provide a 30-year guarantee, we utilize seamless technologies that turn your extension, garage, or commercial unit into a single, impenetrable "tanking" system.
1. GRP Fibreglass (The "Boat Hull" Solution)
GRP is our most requested system for residential extensions in Cork. It is a cold-applied liquid resin that hardens into a tough, impact-resistant surface.
Zero Seams: No joints mean zero weak points for water to penetrate.
Structural Strength: It is tough enough to be used as a balcony or roof terrace.
UV Stable: It won't "alligator" or crack under the sun like old bitumen felt.
2. EPDM Rubber (The Flexible Specialist)
Ideal for larger flat roofs, EPDM is a high-performance synthetic rubber membrane laid in large single sheets.
Extreme Longevity: EPDM has a life expectancy of over 50 years.
Thermal Resilience: It stays flexible in winter and doesn't brittle in the summer heat.
Cost-Effective: A rapid-install solution for garages and commercial units.
3. High-Performance Multi-Layer Torch-on
For traditional builds, we utilize modern polyester-reinforced bitumen membranes. These are worlds apart from the "felt" of twenty years ago, offering a robust, multi-layer seal with improved elasticity.
Real people. Real workmanship. Real results.
If you can see standing water on your flat roof days after it has stopped raining, your roof has a drainage issue. This extra weight puts immense pressure on your home's structure and accelerates the degradation of the roofing material.
Our Flat Roof Repair Cork service includes a "fall" analysis.
We check if the timber decking has sagged over time.
If it has, we can install tapered insulation or firring strips to re-create a slight slope, ensuring that rainwater runs off into your gutters rather than sitting on your roof.
By fixing the slope, we fix the leak permanently.
While old felt roofs often failed after 10-12 years, a professionally installed GRP (Fibreglass) or EPDM (Rubber) roof can easily last 25 to 30 years with minimal maintenance.
No. While a small amount of "puddling" can occur, water should generally clear within 48 hours of rainfall. If it stays longer, it’s a sign of poor drainage or sagging timbers that need to be addressed to prevent future leaks.
Most domestic flat roofs are designed for occasional maintenance access only. However, if you want to use your roof as a balcony or terrace, we can install a heavy-duty GRP system with a non-slip finish specifically designed for foot traffic.
For permanent GRP or felt work, the surface needs to be dry. However, we carry emergency "wet-apply" waterproofing compounds that allow us to seal a leak during a storm to prevent internal damage until the weather clears for a permanent fix.
A simple patch repair is very affordable. If the timber decking underneath has rotted due to long-term neglect, the cost will increase. We provide free inspections to give you an accurate, no-surprise quote.
Flat roofing requires a higher level of precision than pitched roofing because water doesn't naturally run off it. We are fully insured specialists who understand the chemistry of modern resins and rubbers.
We ensure that your roof is not only watertight but also properly ventilated to prevent internal condensation and timber rot.
We serve all areas, including Cork City, Ballincollig, Douglas, Carrigaline, and Glanmire. When you choose Hallmark, you get a fixed-price quote and a guarantee that your flat roof will remain a "dry" part of your home for decades.
Contact us today at (021) 202 1045 for an honest, expert opinion on your flat roof.
Hallmark Roofing provides trusted, affordable roofing services across Cork City and County. With over 15 years of experience, our fully trained and insured team delivers high-quality roof repairs, new roofs, flat roofing solutions, guttering, chimney work and more.
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