Trying to create your own flat roof inspection checklist? If you are, then you must understand it needs to go beyond the simple leak-hunting adventure most property owners and in-house engineers do. Leaks are just a small part of the problem. Roofs face huge adversity as much as the walls, windows, and doors of your property put up with daily.

A building with a flat roof colored in gray

Before jumping into the roofing inspection checklist, one must know their roof’s material before anything else to know the inspection and maintenance frequency needed for each kind of membrane.

Know Your Flat Roofing Material

Before constructing your checklist, be sure to know about every roofing material. From tar & gravel to asphalt, metal, and synthetic membranes, each has their respective strengths and vulnerabilities. Both affect its lifespan and durability. Know more about some of them.

Synthetic Membranes

Synthetic roofs made from ethylene propylene diene monomer (EPDM), thermoplastic polyolefin (TPO), and polyvinyl chloride (PVC) are modern membranes that are more affordable than metal or traditional roofing material but deliver almost the same durability and benefits of both.

EPDM roofs withstand different temperatures and weather conditions. It blocks UV rays from entering the house and introduces a watertight seal that guarantees no leakage. TPO roofs have further material reinforcement allowing it to deliver better airtight seals and UV ray reflection because of its lighter colors. PVC roofs are the strongest synthetic membranes available being able to carry HVAC systems without creating any tear or penetration on its airtight roof.


Metal roofs are as strong as traditional roofing materials. With careful maintenance, they can last up to 50 years. However, stainless and aluminum metal roofs are the most expensive at $15 per square foot. However, they require the least amount of maintenance among other flat roofing materials. In addition, they are durable, easy to repair, and the least prone to leakage.


A flat roof inspection checklist has plenty of items to check off for traditional material inspections. Tar and gravel roofs are durable. However, the gravel hides unseen sandwiched barrier cracks possibly caused by temperature changes or heavy rain. In contrast, their affordability and lifespan that can reach up to 40 years offsets this small disadvantage.

Asphalt, which engineers use to create roads and bridges, has a lengthy lifespan of 50 years without much maintenance. However, frequent temperature changes will cause cracks to appear on the material. This is easily reparable. If incorrectly installed, asphalt roofs with lacking support joists will cause severe structural damage.

8 Things That Should Always Be Present in a Flat Roof Inspection Checklist


Contractors always look for leakage as part of their inspection checklist because all flat roofs are prone to ponding. If left unattended, the ponds of water that rainstorms leave will apply consistent pressure on the material. As a result, it will cause penetration that leads to leakage. All synthetic and traditional materials are prone to ponding. Metal roofs face the risk of rusting with ponding, which will create leakage as well. Any signs of rust, penetration, and large pools of water is a potential leakage threat.

Surface Degradation

Every day, roofing materials face changing temperatures, the ire of violent weather, foot traffic, and the pressure of heavy rooftop equipment such as HVAC vents and others. Over time, these will cause granular loss, holes, punctures, or blisters for all synthetic, metal, and traditional roofing membranes. If you find structural deformations, debris, dirt, rotting, and rusts, make sure to inspect these areas in-depth to check if you need to patch an area of your roof.


Waterproofing membranes and special roofing cement help create air and watertight seals throughout the membrane of your roof. These sealants help keep water off the base flashing and reglets. Check the corners of all your penetrative vents, plumbing collars, coping joints, and other structural openings sealant occupies. If you find any drying, cracking, or deterioration, make sure to take a note.

Drain Blockage

Strong rainstorms will introduce ponding. However, an ineffective drain will increase ponding frequency on most flat roofs. This makes them an imperative part of any inspection checklist.

Leaves, rooftop material debris, possible bodies of small animals, and waste materials left on the roof (for most commercial properties with skydecks for bars or gardens), can get inside drainage systems. Be sure to inspect them thoroughly using a snake camera or any observation equipment.

Ventilation Blockage

Blocked vents with uneven temperatures will melt certain synthetic materials and introduce cracks to traditional materials. Blocked HVAC vents will not only damage the equipment, but its high temperature will compromise the durability of any roofing membrane. Damaged and blocked vents will cause structural damage as well. Make sure to have teams inspect vents and conduct regular cleaning and maintenance. This will not only prevent roof damage but also preserve the lifespan of your ventilation equipment.

Presence of Fungus

The presence of molds, algae, and fungi is detrimental to the health of your roof and the occupants of the structure. Molds signify moistness and damp areas. In traditional materials, these small organisms will weaken your roofing membrane through consistent moisture and damping. They can also rot wooden and steel roofing foundations. Contractors always include fungal and lifeform inspection of roofs in their checklist.

Structural Damage

Exterior roofing structural damage come in the form of blisters, brittles, cracking, punctures, and tears. On the other hand, interior structural damage appear as damaged joists due to roofing material weight (common with asphalt and tar and gravel roofs), molds and mildew on wooden and steel joists, weakening and cracking sealants on reglets, and others. Any small or big interior or exterior structural damage property owners should not take lightly. These small problems can become bigger if not addressed as quickly as possible.

Roof Age

Lastly, contractors take note of the age of the roofing material. They are certain that older material is prone to more brittles, bristling, granular damages, and eventual leakage and penetration. The age allows them to estimate the possible repairs needed for, the durability, and lifespan of the roof.


A flat roof inspection checklist must consider every small and big aspect of possible damages on a roof. Any damage that looks inconsequential property owners should take note. These small issues will evolve into bigger and more expensive problems later on. However, you might miss a few things if you’re taking on inspections on your own. It might be wiser to consult professional roofing contractors to help you see the extent of damage your roof has suffered.