Identifying Common Roof Problems

Learn How to Detect Common Problems with Roofing

Many contractors are assigned with one difficult task to accomplish: How to identify roof problems. Here is our list of common areas on where to inspect and discover those roof problems. Although there could be different areas that you have to investigate, these are the most repeated scenarios.


Rotting roof
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Roof material deteriorates with the direct exposure to weather inclemencies. Inorganic roofing materials are less susceptible than ​organic materials. Exposure to pollutants or industrial atmosphere may accelerate the decay of your roofing material.

Lack of Maintenance

deteriorated roof
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This is most common on flat or low-sloped roofs. Failure to correct uneven roof will cause accumulation of sediments and water that will eventually destroy your material.

Design Problems

Roof in mid-repair
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Design related problems are expensive to correct, and normally the corrections must be done while the replacement of the roofing material is undergoing. Some examples are:

  • Weak structure supporting the roof that might deflect excessively under active loads.
  • Improper roof slope, sagging roof or inadequate drainage system, resulting in accumulation of water.
  • Incorrect system to allow expansion and contraction of changes in deck material or changes in direction.
  • Incompatible roof materials.


damaged roof shingles
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The vacuum and the uplifting pressure created by wind, blowing over the edge of the roof, can partially rip the roofing membrane or system that has been applied. The roofing and insulation must be fastened and secured to the perimeter and to the main roof structure to counteract the forces that are being exerted on the roof.

Flashing Material

Roof flashing around chimney
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The function of the flashing is to provide a seal, a watertight seal, between roofing materials, roof sections and other parts of the building. This is an area that should be carefully inspected prior to any other areas. Incorrect installation procedure or attachment, and improper sealing of the flashing will allow the water to enter between the roofing systems and the roof structure. Sometimes, installing a flashing over a joint or cap will eliminate the problem if it is detected early in the construction.

Base Flashing

Man working on roof
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Base-flashing problems also present some serious and important areas that you must inspect. Some common causes are:

  • Insufficient number of base-flashing piles.
  • Improper height.
  • Insufficient overlaps.
  • Poor adhesion.
  • Incorrect fastening to the surface.
  • Insufficient coating.
  • Loose insulation below.

Penetration Flashings

installing flashing around a chimney
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Either small or large penetration flashing can fail in several ways. As a matter of example:

  • Improper design.
  • Broken seams in metal curbs due to building movement.
  • Deteriorated counter flashing.
  • Improper finishing of metal surfaces.
  • Standing water behind penetration curbs.

Drain Flashing

Happy roofer
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It is not a simple as installing lots of drain openings. The building’s drain system should consist of reasonable drain openings, adequate pitch from high point to drainage components. It is a good practice to include overflow scuppers through different areas to avoid accumulation of water in case on an emergency. Proper maintenance should be given to all of these areas.

Rooftop Equipments

Roofer installing solar panels
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It is very easy to install the A/C compressor, the satellite antenna and other components directly to the surface. Proper attention should be given when this kind of equipment is being installed. They should never be mounted or placed directly to the top of the roof membrane. They should be mounted to a support structure or to raised curb-type supports. Flat flange or curb flashing can then be used to keep the roof watertight, and roof replacement and recovering can be done without disturbing or removing the equipment.

Metal Base Flashings

installing flashing
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These types of flashing will separate easily from bituminous materials. The expansion and contraction rate of these two materials will produce cracks and openings that will allow the water to enter and damage the surface. For these reasons, metal base flashing should be replaced with bituminous base flashing whenever possible.