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Watch Out For Standing Water On Your Roof

Are you wondering where that moldy smell is coming from? Perhaps it’s the standing water on your roof.

Your roof is typically the first defense line from natural hazards, for instance wind, fire, and extreme heat. It’s also your home’s most vulnerable part because it’s exposed to weather and other elements on a daily basis, increasing the likelihood of damage.

One of the sources of roof damage is standing water, which could result in various consequences. If you’re wondering how standing water can be problematic, here’s why.

What is Standing Water?

Standing water denotes any water that hasn’t dissipated or drained within 48 hours on a roof. This water doesn’t flow and can occur following severe storms, excess rains, or other natural events.

However, standing water can also arise from human activities. You’ll discover that this type of water can arise virtually anywhere and at any time throughout the year. Once your roof has standing water, it usually forms a vicious cycle that ends with replacement or repairs.

Causes of Standing Water

  • Obstructed or Inadequate Roof Drainage

This is a common cause for standing water especially in flat roofs. Fortunately, planned roof maintenance can easily rectify this problem. Flat roofs typically drain via roof drains or by sloping towards gutters. When the drains or gutters are clean and enable water flow, standing water issues decrease considerably.

  • Saturated or Compressed Roof Insulation

Standing water can arise due to insulation that has been compressed or crashed down by HVAC equipment or heavy roofing materials throughout a construction project.

Another source of standing water is saturated roof insulation owing to a leak or degradation. Numerous kinds of insulation for flat roofs exhibit water sensitivity and will rapidly dissolve or degrade when wet.

As the degraded insulation starts dissolving and losing shape, water then pools in the indentation. Rectification of this kind of standing water can occur by substituting the degraded and saturated roofing insulation.

Effects of Standing Water

  • Premature aging and cover deterioration

Protracted standing water can result in deterioration and premature aging of the cover, generating leaks. Undetected leaks can cause rust in steel-made roof decks and rot in wood decks. Moreover, excess standing water can produce considerable additional weight, which could weaken your roof’s deck.

  • Mold

Mold is a fungus that needs moisture for growth. Therefore, standing water on roofs offers the ideal environment for the fungus to thrive.

The mold can cause roof discoloration, causing damage to shingles over a period. If left unchecked, the fungus can spread throughout your home’s structure, to the HVAC system and to the rest of the home where it can invade furniture, carpets, and clothing.

  • Roof Collapse

The increase of standing water on a roof implies an increase in the weight a roof must bear. If you don’t handle the problem, the water is likely to surpass the roof’s intended weight threshold, potentially resulting in collapse.

This situation can be very dangerous especially if excess water accumulates. The collapse could potentially cause equipment damage, and worst of all, take lives.

  • Deformation of the deck structure

Standing water can increase the weight on roof decks. The increase of deck deflections can occur as water accumulates, resulting in further standing water, which could compromise the deck’s structural integrity.

  • Growth of vegetation and algae

When water stands for extended periods, the growth of algae and vegetation is likely to occur. This may potentially damage the roof membrane. Moreover, vegetation and other debris can block drains, worsening the situation.

An additional issue with vegetation growth is that the penetration of roots can occur through your roof’s membrane, causing leakage. Damage from vegetation can be pervasive and significant. Nevertheless, regular inspection can draw your attention to a budding issue before further damage occurs.

If you think standing water doesn’t have effects on your roof, this guide will prove otherwise.

Are you having trouble dealing with mold growth in your home? Please contact us for a solution: (416)414-5690

This entry was posted in Mold Facts, Mold Inspection, Water Damage Inspection and tagged , . Bookmark the permalink.

4936 Yonge Street, Suite 240
Toronto, ON

TEL. (416) 414-5690

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