Roofing Experts | ACS | NorCal

The Six Most Common Roof Maintenance Problems

These are the most common problems we find when doing commercial roof maintenance:

Clogged drain with boots and pine needles.

1) Drainage Problems

We find a lot of dirt and debris on roofs, especially in complexes that have a lot of tall trees.

We love trees, but they leave behind a lot of leaves or needles that can clog drains or gutters. If your property has a lot of them, it’s best to remove this debris annually.

If you don’t, it can clog up and rusts out your gutters. If you have a flat roof, it can clog your drains leading to ponding and structural damage.

Rusted Pipejack with gaping hole caused by rust.2) Open Penetrations

Flanges, vents, and drains are tied into the roof membrane using petroleum-based products.

The sun and heat can quickly dry out their oils, making them brittle and prone to cracking.

Combined with the natural shifting on a roof, this often leads to problems.

3) Damaged Membrane

Heavy rains and wind, foot traffic, construction, or mechanical installation cause damage to a roof.

Also, it’s not uncommon to find nails in the plywood deck that have worked their way up through the cap sheet.

Finally, if you don’t have a roof coating, the membrane can become dry and brittle, making it more prone to splitting.

Pro tip: Roof coatings can help it last indefinitely.

4) Rusting HVAC Equipment

Water routinely ponds on ducting and rusts it out, allowing water to get into the ducts infiltrate the building.

 Plant growing in ponding water on roof.5) Water Ponding

If a roof isn’t properly sloped, or drains get clogged from trash or leaves, pools of sitting water can form.

A gallon of water weighs eight pounds.

That adds up quickly.

If the water doesn’t drain, it can cause the roof to sag, which leads to more sagging. It can “boost” the water into places it normally wouldn’t reach.

6) Roof Age

Commercial roofs usually last between 10 and 20 years, depending on the type of roof and how well it was maintained.

Here’s the kicker:

The roof may look normal, with no visible holes in the membrane, but it still leaks.

My dad told me a story about how he was on a roof like this. It looked great. The granules were still in place and everything looked normal. On closer inspection, he found tiny pores throughout the membrane.

Strangely, the material between the sheet’s fibers had completely eroded, causing leakage on a roof with no apparent damage.

This is the deal:

Regular maintenance can greatly extend a commercial roof’s life, but eventually, every roof needs to be replaced.

However, an elastomeric or silicone roof coating can GREATLY extend the life of your roof for significantly less than a re-roof.

How Can You Keep Your Roof Leak Free For As Long As Possible?

Regular roof inspections keep small problems from becoming big problems. After examining your roof, we’ll make recommendations. Common suggestions include:

  • Clean your roof and gutters to minimize drainage issues or water ponding
  • Remove dirt and debris
  • Fix cracks in flashing, penetrations or the membrane
  • Fix rusting HVAC ducts


That’s not to say these are problems on your roof, just that they are common. We have to look at your roof to see if it has any of these issues.

About Allied Construction Services

For more than 20 years, we’ve installed a variety of roofing solutions including TPO, PVC, acrylic and silicone roof coating systems. We provide waterproofing and leak repair services to commercial buildings in San Jose, San Francisco, Oakland, Santa Rosa, Sacramento, and Stockton.

Is your roof ready for the rains? Our roof maintenance packages come with a no-leak workmanship guarantee »

Gotta roof problem? Don’t delay. Call ACS today at (925) 548-9748!

About the Author

Donovan Rittenbach Jr. is the digital marketing manager at ACS. He is a photographer, web developer and copywriter.

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