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Most Common Flat Roof Problems:

These problems are the most common and the conditions that can either cause or be the result of premature failure and reduced service life of low-sloped roofs.  Unforeseen roof problems usually become a significant expense.  Unfortunately, problems are inevitable as a low-slope roof ages. Without proper and routine maintenance, these minor problems can even become catastrophic.


Roof Leaks and Moisture
With any roof, if you have roof leaks, then you have the potential for bigger problems. Leaks can occur for a number of reasons.  The majority of roof leaks will occur at the flashing details, that is, anywhere the membrane is terminated or interrupted . This is why Mainland pays special attention to all the details on a roof and makes sure that all flashings will last as long as the life of the roof.

Blow-Offs, Tenting, Reduced Wind Uplift Resistance and Billowing
Once moisture enters a roofing system, the uplift resistance is greatly compromised.  If perlite or fiberboard insulation gets wet, all uplift resistance is lost!  On a concrete deck substrate, a puncture can go unnoticed for some time and water pools over the deck and saturates the system.

Poor Installation and Unsatisfactory Workmanship
A faulty installation dramatically increases the likelihood of problems and reduces a roof system's life expectancy. Problems with adhesion can result when the area isn't cleaned, dried, or primed properly prior to installation.  Material preparation is important to a quality installation. Sheets installed that have not been relaxed or are installed when ambient conditions such as temperature are not right can result in wrinkles, leaks, fish mouths, contraction of sheets, or blisters. Mainland and all of its crews are educated in proper installation techniques specific to the roof we are installing.

Lack of maintenance
Being wise to problems can prevent their escalation. The problem in roofing is a lack of education at all levels. Scheduled  maintenance is required to prolong the life of a roof and prevent resulting interior damages.  Something as simple as debris on a roof can clog drains and cause a roof to fail or even collapse.  Regular maintenance should not be neglected.

Ponding Water
If we move the water off the roof, the roof has a really good chance of performing the way it should. Algae growth from ponding water deteriorates the roof. Slope can be added with tapered insulation and crickets.

Punctures and the Installation of Penetrations after Roof Installation
For all owners, but especially those with single-ply or spray polyurethane foam (SPF) roof systems, damage from foot traffic can be very problematic. One of the things we like to do is add walkway paths or extra sacrificial layers of membrane.

Improper Repairs
Using materials that are not intended for application on specific roof types can result in permanent damage to the roof. You can make a small problem worse through an improper repair.

Shrinkage of Membrane
Some membranes shrink with time, especially Modified Bitumen and Single Ply.  Failure can occur on perimeter edge and laps of membranes.

Blistering
Blistering, ridging, splitting, and surface erosion are symptomatic with flat roofs and can eventually lead to bigger problems. While blisters are not always worth fixing, one of significant size should be addressed as it may rupture. Inadequate attachment of hot tar roofs due to asphalt heated to an improper temperature can cause blistering, along with the slipping of felts and accelerated aging.  Moisture and air trapped in roofs can vaporize, causing blisters.  Spray polyurethane foam (SPF) roofs a very prone to blister and can rupture from foot traffic.  It is very common for us to see a fairly new roof installed by other contractors that are blistering through out.  Whenever possible, we like to install GAF's Stratavent venting base sheet to eliminate this problem.

Poor Design
A poorly designed roof is bound to give you problems.  Most roof problems can be avoided by anticipating them and building the solution into the design of the new roof.  This is where our experience and attention to detail is most evident.

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