Roof Leaks and Mold

Brushes, rubber gloves, and cleaning supplies to clean a home for the holidays

When most people think of rain and roofing, they think of the melodic tapping of raindrops on the roofing keeping them safe and dry, not massive property damage. While often thought to be of little concern, roofing leaks can cause some of the most costly damage that can befall a home with mold being particularly destructive.

Why You Should Care About a Leaky Roof

To make matters worse a leaky roof is more than just a cosmetic problem as when left untreated water intrusion can quickly both a structural and health issue as well. Indeed as the water works its way through the structure of the home causing shorted wires, foundation instability, and mold growth, the last of which can cause serious health complications.

The best way to prevent any of these issues is to immediately deal with any roof leaks you discover. It is inadvisable to leave a leak for any length of time as while the cost of the repair may be considerable, the cost of solving the mold and other structural issues will quickly dwarf any roofing work that may be needed.


Roof Leaks and Insurance

To further incentivize you to act quickly when confronted with a leak is the fact that most insurance policies will not cover the cost of repairs to the damage caused by a leaky roof you have left after discovery either due to very particular coverage or the extent of the damage. Indeed most policies will cover the first signs of a leak and damage, but will not apply to the extensive damage that will come about from you ignoring clear signs of damage for an extended period.

This is in step with the fact that most home insurance will only cover damage that is “sudden and accidental” not damage from neglected maintenance. An important stipulation to remember because insurance companies can claim that even the failure to detect a roof leaks can constitute as negligence and void your policy and since it can take months for a leak to show up in the interior, this means the damage can be extensive before you can easily detect the leak.


Common Causes of Roof Leaks

In order to detect roof leaks before they become an issue and before they may be visible in the interior of your home it is important to familiarize yourself with what may cause a leak to form in the first place. Indeed a leak can be caused by a variety of occurrences including, but not limited to, hail, heavy rains or snowfall, high winds, and ice dams, or by improperly installed or worn down roofing materials.

The most common causes include:


Incorrectly installed or broken flashing– Water can easily enter into your home if the metal flashing surrounding your chimney, skylights, vent pipes, or dormer windows is damaged or improperly installed.

Missing or broken shingles– shingles are particularly prone to becoming damaged during strong storms, where hail can break them or high winds can blow them away. If a shingle is indeed missing it is very easy to identify, however, a broken shingle may require a more thorough inspection to discover.

Incorrectly installed or damaged skylights– The improper installation of a skylight or the decay of its insulation along the edges will freely allow water into your home to cause damage.

Improperly sealed valleys– If the places where the two planes of your roof come together, otherwise known as the valleys, are not sealed correctly then rainwater can easily run into the home as it runs down the roof.

Blocked Gutters- When gutters become blocked it prevents the proper drainage of rainwater, causing the water to pool in one section of the roof, where it will quickly find a way inside.

Incorrect roofing materials– different roofing materials are designed for different types of roofs if a roof is constructed with the wrong kind of materials for its design, leaking can occur.

Ice Dams- An ice dam is when a line of ice forms at the edge of a roof and prevents the water created by melting snow from draining off, causing the water to back up and leak into the home.


Common Signs of a Roofing Leak

Now that you know the causes of a leaking roof, it is important to educate yourself on the signs that your roof is indeed leaking to both identify leaks as soon as they appear and to prevent further damage from occurring.

The most common signs of a leaking roof are:

leaking roofs

  • Water appearing in the home during heavy rainfall or in spring when the snow melts.
  • A darkening of the ceiling.
  • Cracked or bubbled plaster.
  • Peeling paint around skylights and dormer windows.
  • Drywall crumbling.
  • Wood decay throughout the home.
  • A musty smell in the attic.
  • Decreased energy efficiency in your home.
  • Curling shingles.
  • Water spots on the walls and ceilings.
  • Lowering of the air quality within your home.
  • The presence of mold within your home.

Though being able to recognize the signs of a leaking roof is an important skill for any homeowner to have, being able to locate the leak is an even more useful, and difficult to acquire, skill. Indeed, since water can essentially enter the home from anywhere, the source of a leak can be a challenge to find, and in many cases requires a professional inspection to locate. While often overlooked an inspection is a service that can save you a lot of money in the long run by locating a leak fast before too much damage has occurred.


Mold and Roofing Leaks

One of the most devastating results of a leaky roof is that harmful mold growth can explode and infest a home within as little as a few days. When water enters the home through a leak and has the chance to stagnate, molds spores quickly begin to germinate and from within the moist surface. This process can take as little as 48 hours when the necessary conditions, those of water and food, are present.

The two types of mold growth that are commonly associated with roof leaks are:

Limited growth– Which occurs when there is good enough ventilation to prevent condensation and limit moisture except in the area around the leak. This limits the growth of the mold and means that limited growth can be dealt with by killing the spores around the leak then fixing the leak.

Systematic growth-Systematic growth happens when there is enough significant moisture buildup to cause the facilitate the growth of mold throughout the entirety of the attic. Systematic growth will in nearly all cases require professional intervention.

In either case, it is critical to deal with the mold quickly as if it spreads it will release spires that can be picked up into your homes HVAC system and cause massive respiratory and other health issues. TO deal with the mold there are two critical steps:

  1. Leak repair-You need to have the leak repaired, preferably by a licensed roofing contractor, to prevent the entry of further moisture and the recurrence of the mold.
  2. Mold Remediation- In order to deal with the mold, it is strongly recommended that you employ professional mold remediation services who will inspect for, contain, deodorize, and remove mold and mold damage.



In order to prevent from water damaging your home and the complications that come with such damage, it is advisable to locate and address roof leaks as soon as they appear, and if there is already damage, have it dealt with professionally.