How Freezing Temperatures Can Cause Roof Leaks...Even in Florida!

Did you know that Florida freezes can cause your roof to leak? That’s right, many building owners and managers are unaware of the dangers a freeze can have on your roof. Let’s take a look at what water does when it freezes and how it creates a roof leak.

When moisture is on your roof, whether through rain, dew, ponding water or HVAC discharge, it tends to pond in areas. For instance, rain ponding on a poorly maintained pitch pocket. Most liquids have a quite simple behavior when they are cooled (at a fixed pressure): they shrink. The liquids contract as it is cooled; because the molecules are moving slower they are less able to overcome the attractive intermolecular forces drawing them closer to each other. Then the freezing temperature is reached, and the substance solidifies which causes it to contract some more because crystalline solids are usually tightly packed.

Water is one of the few exceptions to this behavior, which is a problem to your roof. When liquid water is cooled, it contracts like one would expect until a temperature of approximately 4 degrees Celsius (39.2 degrees Fahrenheit) is reached. After that, it expands slightly until it reaches the freezing point of 0 degrees Celsius (32 degrees Fahrenheit), and then when it freezes it expands by approximately 9%, which herein lies the problem to your roof.

All the moisture that was trapped in the little cracks and voids in the roof and flashing will expand and make them much worse. Over the course of several freezes, these thermal ‘shock cycles’ create openings and cracks for water intrusion under the membrane, into the roof system, ultimately resulting in a roof leak.

How can you prevent this from occurring? There are two important steps. First, we need to make sure moisture is getting off of the roofing system. This means ensuring proper drainage, no areas or flashings that can hold water and confirming that all HVAC units have condensation lines that run to the drainage ports and are fully connected. Second, we have to make sure all voids, cracks and damage to the roof is addressed and sealed accordingly. This includes pitch pockets, membrane voids, counter flashing sealants, etc.

With a few proper precautions and actions steps, we can ensure that your roof is protected when those night temperatures begin to drop below freezing, or better as you learned, 39.2 degrees.

More Real Life Roofing Horrors!!!

Arsenic and an Old Roof
Picture a hazardous waste containment facility with large tanks of arsenic being stored until it could be properly disposed. The vats were sitting on concrete secondary containment. The owner hired an unlicensed consultant to design a new roof for the building, who gave the project to a friend of his to re-cover a built-up roof and even added a little extra gravel to the roof to be sure it was well covered.

After the new roof was installed, there were approximately 10 pounds per square foot of built-up roofing and 17 pounds per square foot of re-cover roofing material on a structural steel deck designed for 20 pounds dead load per square foot and 20 pounds live load per square foot. In addition, re-cover drains were installed that reduced the size of the drainage pipes to about one-third of the required amount.

Because the size of the drains were reduced, the water built up on the roof to the overflows during the next heavy rain — four inches of water at waters weight of approximately 62 pounds per cubic foot. Guess what ended up with the arsenic in the secondary containment? You do the math.

Moral: Hire a competent contractor who makes sure the structure can withstand the weight of the designed roof.

Have You Become Complacent?

Since the destructive 2004 and 2005 hurricane seasons, only 4 hurricanes have made a U.S. landfall, all doing so in the western half of the Gulf of Mexico, most notably, September 2008’s Hurricane Ike.

Furthermore, since Hurricane Ike’s destructive rampage, the U.S. has had only a few hurricane “close-calls” the past 2 seasons.

Complacency makes you less attentive, less aware, less able to react when a serious situation presents itself.

As the U.S. faces a potential tropical threat later this week from Hurricane Irene, a major concern among meteorologists is “hurricane preparedness complacency”.

Do you know what the condition of your roof is? Will it be able to withstand hurricane or tropical force winds? Are the drains functioning properly to effectively and quickly remove the water to avoid ponding water?

It is not necessary to be in the direct path of a hurricane to feel and experience the effects of it. Don’t ever assume you are safe. It is always better to be prepared, rather than left picking up the pieces.

For more information on preparation, visit: http://www.ramconroofing.com/hurricane.htm. Or call RAMCON at 1-877-726-2661 to speak to a roofing expert today!

Evaluating The Roofing System After A Storm

You can’t do much to repair or maintain a roof while the storm is underway; a roof isn’t a safe place to be in bad weather. First and foremost, if you sense problems during a storm like ceiling tiles falling or sprinklers popping, indications that the roof may be caving in, you’ll want to evacuate the building immediately.

Once you’ve taken all the steps you can to ensure the roof will weather the storm (best achieved with an inspection from RAMCON), what happens when it’s over? It’s wise to perform a post storm roof inspection.

Evaluate the Damage
As soon as it’s safe to examine the roof, it’s important that we do so. RAMCON has teams that specialize in post-storm inspections and can quickly and effectively inspect the roof for any substantial damage.

As we review the system, taking action may be warranted. Anything that’s causing leaks is top priority and needs attention as soon as possible. Damage to the membrane, such as cuts, punctures and voids, needs to be addressed. It’s also vital to check the roof drains and gutters to see if they became clogged, which is common in a strong storm with debris flying around.

Similarly, we’ll need to see whether any metal flashings have come loose, creating a risk of water getting behind the flashing and into the facility. If the roof has multiple levels, we will pay particular attention to the intersections of the walls and roof levels to make sure nothing has been dislodged.

Also on the checklist: listening for a crunching sound as we walk the roof. That may indicate that the roof actually was lifted by the storm and is settling back into place as you walk over it, if that happens, we need to check it further. We may see that the fasteners have backed up and penetrated the roof membrane, so that they may cause leaks when the next storm hits.  Several areas warrant checking that might not be apparent at first glance. For instance, we confirm that all penetrations and penetration flashings remain firmly attached to the roof. The same goes for any equipment screens, which should be “storm-worthy for the next event”.

While roof maintenance often takes a back seat to other priorities on your “To-Do” list, it is an important part of managing and looking after the asset. An ongoing maintenance program can prevent more serious and costly problems down the road.

Talking About Counter-Flashing

All roofs have to end somewhere. Either they terminate at a wall, parapet, expansion joint, metal edge or a tie-in with another roof. In all cases, where the roof ends, there is a weak link. Walls and parapets require vertical flashings. The flashings are generally attached at the top to keep them from sliding down the wall. The flashing attachment is usually screws, concrete fasteners, nails, or some other fastener fastened through a termination bar — a flat strip of metal with pre-punched holes. Termination bars are supposed to provide attachment along its entire length because it will continuously press against the wall.

Most roof manufacturers understand that this is a weak point in the roof and require a counter-flashing. A counter-flashing is a material, usually metal, that covers the upper edge of the flashing to divert water away from it. If the counter-flashing is not properly installed, water can get behind it and the membrane flashings. The counter-flashing then requires a sealant to be applied at the top.

This problem is just a sample of the considerations that need to be addressed in designing, installing and maintaining a roof. A good understanding of how a roof actually works and knowledge of the strengths and limitations of the different types of roofing systems is essential for the long-term performance of any roof system. The roof system should be designed with the particular building in mind, not just which is cheapest.