Commercial Roof Drain Repair: The Ultimate Fix for Leaking Drains

Updated at: 17/03/2025

A leaking commercial roof drain is more than just an inconvenience; it's a significant threat to your building's structural integrity and can lead to costly water damage, mold growth, and business disruptions. Ignoring a problematic drain only exacerbates the issue, potentially leading to extensive repairs and prolonged downtime. From minor clogs to severe corrosion, the underlying causes of these leaks are diverse and often require specialized expertise to diagnose and resolve effectively. The consequences of inaction are simply too great to risk.

This article provides the ultimate guide to commercial roof drain repair, offering a comprehensive understanding of common problems and their solutions. We'll take you through a detailed, step-by-step process for identifying the source of the leak, selecting the appropriate repair method, and ensuring a long-lasting, watertight seal. Ready to tackle those pesky leaks and protect your investment? Let's begin.

Preparation and Safety Guidelines

Tools Needed
  • Membrane
  • Heat source (torch)
  • Adhesive
  • Scraper
Safety Guidelines
  • Always prioritize safety! Wear appropriate safety gear, including hard hats, safety harnesses, and fall protection when working on a roof. Commercial roofs are often high and dangerous.
  • Never attempt repairs if you lack the proper experience or training. Roof drainage systems are complex; improper repair can worsen the problem and cause further damage. Hire a qualified professional if needed.
  • Turn off any power to the area before starting repairs, especially if working near electrical equipment or wires. This prevents the risk of electrical shock.

Step-by-Step Instructions

  1. Prepare the Drain Area

    • Clean the surface of the original roof around the drain.
    • Remove any previous, faulty repairs. In this case, the previous repair involved a membrane and tar over the existing stone, which failed.
    • Scrape away any damaged stone around the drain.
    Scrape away any damaged stone around the drain.Scrape away any damaged stone around the drain.Scrape away any damaged stone around the drain.
    Prepare the Drain Area

  2. Repair the Drain Basin

    • If the drain basin itself is cracked (as in this case), remove the damaged ring. Remove some material around the cracked area of the drain basin to facilitate proper membrane application.
    • Apply membrane over the repaired drain basin, ensuring a proper seal.
    • Replace the drain ring.
    Replace the drain ring.Replace the drain ring.Replace the drain ring.
    Repair the Drain Basin

  3. Apply and Seal the Membrane

    • Apply a membrane, creating a proper transition from the roof to the drain basin. Ensure the membrane extends into the drain basin to eliminate seams.
    • heating may be required for some membrane types, but this case doesn't seem to necessitate it)
    Ensure a proper bond between the membrane and the roof surface, preventing future leaks. (Note: heating may be required for some membrane types, but this case doesn't seem to necessitate it)Ensure a proper bond between the membrane and the roof surface, preventing future leaks. (Note: heating may be required for some membrane types, but this case doesn't seem to necessitate it)
    Apply and Seal the Membrane

Read more: DIY Roof, Shingle, Fence, and Flashing Repair with Henry Wet Patch 208

Tips

  • Proper transitions from the roof to the drain are crucial to prevent leaks. Previous repairs often fail due to improper transitions.
  • Thoroughly clean the roof surface before applying the new membrane.
  • A proper membrane application, extending into the drain basin, creates a seamless, leak-proof solution.
  • If the drain basin is damaged, repair it before applying the membrane.
  • Heating the membrane may be beneficial in certain cases (though not strictly required here) to improve adhesion.

Common Mistakes to Avoid

1. Improper Cleaning of the Drain

Reason: Debris buildup, including leaves, dirt, and other materials, restricts water flow and can lead to backups and leaks.
Solution: Thoroughly clean the drain using appropriate tools and techniques to remove all obstructions and restore proper drainage.

2. Ignoring Minor Leaks

Reason: Small leaks often worsen over time, leading to significant damage to the roof structure and interior of the building. Delaying repairs increases the cost and complexity of the fix.
Solution: Address all leaks promptly, no matter how small they may seem, to prevent escalating damage and costs.

FAQs

How often should I inspect my commercial roof drains?
Ideally, you should inspect your roof drains at least twice a year, once in spring and once in autumn. More frequent inspections are recommended after severe weather events or if you notice any signs of leakage.
What are the signs that I need commercial roof drain repair?
Common signs include water stains on ceilings or walls below the roof, pooling water on the roof near drains, slow draining, visible cracks or damage around the drain, and foul odors emanating from the drain.