You need to work smart when it comes to inspecting a commercial flat roof. Instead of doing comprehensive preliminary inspections, inspect the most vulnerable parts of your roof one by one. Allied Construction Services, a top commercial roofing contractor in the state, recommends you inspect these parts in the following order. 

Gutter and Drains 

Flat roofs aren’t completely flat; they’re slightly elevated to ensure rainwater flows to the drains. But if the drains are clogged, water begins to accumulate. That’s why you should check your roof’s drains and gutters first. 

Standing water on a flat roof is problematic because of several reasons. One of them is the added burden to your flat roof. As a rule of thumb, you shouldn’t leave standing water unattended for more than two days. Part of your roof might collapse under the added weight. Keeping your drains and gutters free of debris can help prevent these issues. 

Rooftop Units 

Rainwater isn’t the only source of moisture on a flat roof. Condensation HVAC units could be dripping onto your roof. Check if the condensation’s draining properly. 

Roof Surface 

Moisture problems and gaps in the roof surface usually go hand in hand. Exposure to UV rays, not to mention foot traffic, can weaken the roof’s surface and create holes. Through these gaps in the surface, water can infiltrate your roof. 

Flashing and Roof Joints 

Water can also infiltrate the roof’s substrate through flashing near the roof edges. These pieces of metal cover gaps in the roof joints. 

Keep in mind that this routine is only for preliminary inspections. We strongly recommend hiring a roofing construction services company to do a comprehensive roof inspection. 

Looking for an experienced contractor in your area? 

Allied Construction Services is a veteran-owned contractor with more than two decades’ worth of experience. We offer professional commercial construction services. For inquiries, call us at

(925) 297-5788. Or leave us a message on this form. We serve homeowners in Livermore, CA.