5 Causes of Commercial Roof Leaks

A commercial roof is a vital component of any building. It protects your inventory, equipment, and employees from the elements. However, leaks can compromise this critical barrier, leading to costly repairs, downtime, and potential safety hazards.

Understanding the common causes of commercial roof leaks is crucial for building owners and property managers. By being proactive with maintenance and inspections, you can identify potential problems early on and prevent leaks before they occur.

5 Reasons That Commercial Roofs Leak

Since every roof is unique, there are as many reasons that commercial roofing might leak as there are roofs. Regardless of the cause, leaks pose significant risks to property integrity and operational continuity. By familiarizing yourself with these common issues, you can take informed steps toward safeguarding your commercial premises against water intrusion.

1. Damaged Roof Membrane or Substrate

The roof membrane is the first line of defense against water intrusion. It’s typically made from materials like modified bitumen, TPO (thermoplastic polyolefin), or PVC (polyvinyl chloride). Over time, these materials can become damaged due to several factors:

• Foot traffic – Commercial roofs are sometimes used for maintenance or equipment access. Excessive foot traffic can puncture the membrane or wear down the protective layer, creating openings for water to seep through.
• Debris – Wind can carry branches, leaves, and other debris onto the roof. These objects can puncture the membrane or clog drains, leading to ponding water.
• Weather – Extreme weather events like hail, heavy rain, and strong winds can take a toll on the roof membrane. Hailstones can cause direct punctures, while strong winds can tear or lift the membrane at its seams. Ultraviolet (UV) rays from the sun can also degrade the membrane over time, making it brittle and more susceptible to damage.

Preventative Measures

• Limit foot traffic. Restrict access to the roof only when necessary for maintenance or repairs. Consider designated walkways or pads to distribute foot traffic and minimize wear on the membrane.
• Have regular inspections. Schedule regular inspections by a qualified roofer to identify and address minor damage before it becomes a major leak. Inspections should be conducted more frequently after severe weather events.
• Remove debris promptly. Don’t let debris accumulate on your roof. Regularly clear leaves, branches, and other objects to prevent them from damaging the membrane or clogging drains.

2. Drainage System Issues (Pooling Water)

A properly designed drainage system is crucial for channeling water away from the roof. If the drainage system is compromised, water can pool on the roof. This ponding water can lead to several problems:

• Increased weight – Standing water adds significant weight to the roof structure, which can lead to premature wear and tear.
• Membrane deterioration – Water that sits on the membrane for extended periods can break down the material and accelerate its degradation.
• Breached seams – The weight of the water can put stress on the seams of the membrane, causing them to split and leak.

Preventative Measures

• Keep drains clear. Regularly clean drains, gutters, and downspouts to ensure they are free of debris and functioning properly.
• Ensure proper roof slope. The roof should have a sufficient slope to direct water towards the drains. If the slope is inadequate, water may pool in certain areas.
• Inspect drains. During inspections, check the drains for damage or blockages. Consider installing drain guards to prevent debris from entering the system.

3. Defective, Damaged, or Deteriorating Seals

Commercial roofs often have various penetrations, such as vents, pipes, and skylights. These penetrations require proper sealing to prevent water infiltration. Seals around these areas are susceptible to damage due to:

• Age and wear – Over time, sealants can dry out, crack, and lose their adhesion.
• Movement – Buildings naturally expand and contract with temperature changes. This movement can cause stress on the seals around penetrations, leading to cracks and leaks.
• Improper installation – If seals are not installed correctly during roof construction, they may not form a watertight connection, allowing water to seep in.

Preventative Measures

• Conduct regular inspections. Pay close attention to the seals around penetrations during roof inspections. Look for signs of cracking, blistering, or separation from the surrounding material.
• Re-seal when needed. Proactive re-sealing of critical areas can prevent leaks before they occur. The frequency of re-sealing will depend on the type of sealant and the specific location on the roof.
• Ensure proper installation: When installing new equipment or modifying the roof, ensure all penetrations are properly sealed using high-quality materials and proper techniques.

4. Flashing Damage or Failure

Flashing can become compromised due to several factors:

• Weather – Exposure to harsh weather conditions like strong winds, hail, and freezing temperatures can cause the metal to rust, warp, or crack.
• Improper installation – If flashing is not installed correctly, it may not create a watertight seal, allowing water to seep in at the seams.
• Age and deterioration – Over time, the metal used for flashing can deteriorate, losing its flexibility and becoming more susceptible to damage.

Preventative Measures

• Conduct regular inspections. Inspect flashing during routine roof maintenance for signs of damage, corrosion, or loose connections.
• Repair or replace flashing as needed. Address any issues with flashing promptly. Minor tears or gaps may be repairable, while severely damaged flashing may need complete replacement.
• Always use quality materials. Ensure that high-quality materials are used for flashing installation to ensure durability and long-term performance.

5. Weather

Extreme weather events can directly damage a commercial roof and lead to leaks. Some of the weather-related concerns include:

• High winds – Strong winds can lift the edges of the membrane or pry flashing loose, creating openings for water to enter. Wind can also carry debris that can damage the roof membrane.
• Hail – Hailstones can puncture the roof membrane, creating direct pathways for water infiltration.
• Heavy rain – While a properly designed roof should handle heavy rain, prolonged downpours can overwhelm a clogged drainage system, leading to ponding water and potential leaks.
• Snow and ice – Heavy snowfall can add significant weight to the roof, putting stress on the structure and potentially causing leaks. Additionally, ice dams can form at the edge of the roof, preventing proper drainage and causing water to back up under the shingles.

Preventative Measures

• Inspect the roof after weather events. Particularly following severe weather, conduct thorough inspections to identify any damage caused by wind, hail, or snow.
• Schedule regular maintenance. Ensure your drainage system is functioning properly to handle heavy rain or snowmelt. Consider installing additional roof drains in areas prone to ponding water.
• Mitigate potential problems when possible. In areas with heavy snowfall, consider installing snow removal systems or roof heat cables to prevent ice dams from forming.

Additional Tips for Commercial Roof Owners

While some problems are unavoidable, there are some steps you can take to protect your commercial roof.

• Consider investing in a roof warranty or maintenance program to ensure regular inspections and receive professional assistance with minor repairs.
• Maintain detailed records of roof inspections, repairs, and maintenance performed. This information will be valuable for tracking the condition of your roof and planning for future maintenance needs.
• Partner with a qualified commercial roofer who is experienced in working on commercial roofs. They can provide valuable advice on preventative measures and repairs specific to your roof type and needs.

By understanding the common causes of commercial roof leaks and implementing preventative measures, you can significantly reduce the risk of water infiltration and protect your building from costly damage.

Your Choice for Commercial Roof Repair (and More)

Whether you need commercial roof repair, installation, or inspections, the Lakeland roofers at Stronghold Roofing & Solar have the experience and skills to handle your needs. From Sarasota to Lakeland, we serve commercial and residential roofs with a commitment to quality and service.

Call today and ask about a free roof estimate!

FAQ’s – Commercial Roof Leaks