The Future of Cool Roofing is Now, and It’s really Green.A. Roofing Leaks and Thermal Shock.

As we enter the hot months of summer, there can be many instances in which ambient temperatures rise more than 30 – 40 degrees in the course of a few hours of the day due to warming rays from the sun.  These dramatic temperature changes (thermal shock) can be very stressful to rubber, asphalt, tar and other traditional roof systems, including membrane and metal roofs, causing leaks to occur as the roof expands and contracts and consequently opens seams and tears.  

Aging metal, Rubber/ EPDM, asphalt roll, and older membrane roofs are particularly susceptible to the dynamics of thermal shock or thermal cycling.

In the case of metal roofs, thermal shock causes movement of the metal panels as the roof heats and cools, consequently opening up seams and loosening fasteners over time. Neoprene fastener washers may simply disintegrate as they age; also creating leaks at key penetration points.   It is very common for facility managers and building contractors to report increases in roof leaks in early spring months after long hot summers and cooling contracting winters that follow.

“Thermal shock” is a term describing the temperature swing in a day. During the day we will get the temperature rising up to 85-95 degrees or more now (average in the summer here in the Mid-Atlantic.  Roofing material will absorb heat and reach temperatures of 150 to 170 degrees or more and then as evening comes about the temperatures drop down to as low as 50-60 degrees by morning.  This swing of 85-95 degrees of the roofing material creates thermal shock.  I’ve worked in areas where we have had 90 degrees during the day with the roofing and roof metals heating up to 150 degrees and then dropping down to 55 degrees or so.   This creates movement, a lot of pressure and pull on the roof.

Heat expands – cold contracts.  Your roof is doing this on a daily basis for years.  I have seen a tear in a roof that was closed in the morning and hard to see but by late afternoon as temperatures rose, the tear became a ½ inch opening.

When your roof was first installed and new it had a lot of flexibility and resistance to this expansion and contraction with the tars, rubber, and asphalt with all their oils.

Keep in mind that roofs are exposed to the elements like wind, heat, rain, cold, and UV twenty four hours a day, 7 days a week, and over time these tar/oil/rubber based products get dried out and lose their flexibility.  This at first is slow to show up in any major or dramatic way but what you will start to notice on the roof is the top layer or cap sheet losing the surface material embedded in it, the mineral granules, mica or solids that are there to help protect it from the sun.  These granules are the protective barrier between the rubber/asphalt/tar based compounds and the sun’s damaging effects.

 

As the roof dries out these protective mineral solids begin to lose their adhesion and start separating from the surface, as well seams begin to open up as the cap is dry and the daily expansion and contraction opens them up by pulling them apart  When this occurs it accelerates the general failure of the cap sheet.   As this continues you will see more and more granules coming off and then strands of fiberglass reinforcing becoming exposed.

As the sun continues to beat down on the roof, it dehydrates or dries out and loses flexibility becoming brittle and no longer water proof.

When you combine the movement in the roof from temperature swings and a dry or brittle condition you start to get areas of the roof separating or pulling apart.  Now your repairs will start.

Please keep in mind that this is all on a gradient taking a number of years.   As the roof continues to dry out the repairs become more frequent with new areas opening up and the old repairs opening up again.  Repair bills eventually mount up until you must reroof again. 

The cycle I have described above happens over a period of 7 to 10 to 15 years, the average service life of a hot mop roof, EPDM( rubber), asphalt roll, etc., depending on geographical location and conditions.  The competence of the roofing contractor, quality of materials used and maintenance over the years can also affect the service life of the roof.

THE CULPRIT:

Thermal shock occurs when a thermal gradient causes different parts of an object to expand by different amounts. This differential expansion can be understood in terms of stress or of strain, equivalently. At some point, this stress can exceed the strength of the material, causing a crack to form. If nothing stops this crack from propagating through the material, it will cause the object's structure to fail.

Failure due to thermal shock can be prevented by: Part 2:

Cooling and Curing Your Commercial Roof Problems

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Cooling the Roof to prevent and mitigate the effects of thermal shock;

An understanding of basic physics is all that’s needed to recognize why cool roofs can help save energy. A cool roof reflects the sun’s rays, thereby preventing them from being transferred into a facility. Additionally, a roof that is highly emissive — one that re-radiates, doesn’t absorb, a high percentage of heat that is returned back to the sky — further reduces the amount of heat transferred into the facility. What this means is that during hot summer months, or any time of

year when a facility is mechanically cooled, the cooling system (HVAC) has to expend less energy to keep the interior at a comfortable temperature.

The key here is to cool the surface of the roof with material that reflects as well as having emissive properties in the material itself. Most coatings have solids which heat up even if the final product is reflective and white. Both properties are need for permanent problem solving on today’s super-hot roofs, and it going to get hotter, a lot hotter.

Most roofs are petroleum based products from asphalt to tar to rubber. These eventually off gas and dry out, then they crack and come apart. Remember, oil and water don’t mix. Most roofs are made from the last bit of petroleum in the bottom of the barrel after all other superior oil based products have been used from the crude. It is gummy and full of heavy metals. This tar/oil is great in the beginning of its roof life, but bad when it starts to break down and dry out, and then these pollutants leach into the ground after rain and storms as the roof deteriorates and breaks down.

This same oil based water repellant property, based on the chemical properties of oil and water not mixing, is why latex and/or water based elastomeric and water based roof coatings, don’t work for very long, if at all ( if they did we would be using them).

1. Latex or water based coatings don’t bond permanently with oil based roofing caps. Water and oil don’t mix means the bond isn’t on a molecular level because the compounds don’t bond permanently. Though they look great when applied; latex, elastomeric, and silicone hybrid bonds will release, dry, and crack leaving water and heat to continue to attack your roof.

Additionally, one of the most common reason these compounds don’t work well is that the surface area being repaired is rarely properly cleaned. Roofs collect and absorb oils from car and truck exhaust, factory waste, and dirt in the air. And, it bakes in over time. The only way too properly clean and present a surface for repair or proper encapsulation, is to hand scrub the roof with heavy detergents (biodegradable) and stiff washing brushes. Pressure washing does not get the oils out. The bonding on the surface is everything for patches, repairs and overlay roofs.

? Coatings?

So why are these latex, elastomeric, silicone and roof coatings so popular? Simply stated, they are cheap to buy, easy to apply, clean up with water (what does that tell you, cheap, and look good as a reflective coating, which promises to extend the life of your roof and all that cost.

The reality is far from the truth as many are finding out. Latex, water based and even silicone coatings dry out and crack, exposing your roof again, the bond is semi-permanent at best and most of the coatings have cheap metals and or ceramics as the solid in the compound/coating. These solids will heat up and transfer the heat to the building. Yes, even if the coating is white. So in short, what was presented as a great money saving extender of your old roof is actually a short term solution which only postpones the now worsening problems on your roof for a very short time, coating over the original after it has started lifting will do you no good. Again, if they worked, we would be using them.

The case for silicone roof coatings is also very similar and as I have not done extensive research on this new product, I will say this based on experience and chemistry I have spent a lifetime of contracting using every silicone caulk and compound on the market and find they are similar to the latex based products, in that heat and water will get them to pull up off of the surface in a relatively short period of time, especially when exposed to direct sunlight and heat. If they worked, we would be using them…

To the statement “If these products worked, we would be using them”.

They are much cheaper to buy, easier to work with, faster to apply, and soap and water clean-up with most. We would be happy to have more money and less hassle. Unfortunately we can’t get behind them, but there is a class of products which address all of the problems we have listed and then some.

Picture: A low VOC, 75% Solids Epoxy Cool Roof Systems

B. The Future of Roofing part 2: Permanent Roofing Solutions.

1. Epoxy Cool Roof Systems:Full and permanent roof encapsulation without the tear off and costly risks.

When the capital improvement budget is lean, it’s easy for facilities executives to find themselves with more potential projects than are financially feasible. A new roof, however necessary it may seem to be, is often passed over because it’s such an easy target for this familiar argument: “Let’s patch it up one more time and see if we can’t get another year out of it.”

However, if the roof really is in dire straits, facilities executives have learned that the energy saving benefits of a cool roof — one that is reflective and emissive solvent based, and permanent — can provide the little extra nudge to move a roof up the project priority list, save money now and down the line.

What may be the clincher, though, or even a way to help upper management “discover” extra capital to fund a project that had previously been deemed deferrable, is that there are several other money saving options; rebates, tax deductions, savings from an energy efficient building envelope, permanent roof encapsulation, strategies, longer air handler life and more. So far, only solvent based epoxy cool roofing systems have been proven to permanently bond to your roofs surface. They save energy, eliminate tear off costs and disposal costs, eliminate future removal and replacement cost, and shave peak demand costs by cooling the building.

So if water based coatings, elastomeric, and silicones eventually dry out, crack, pull up, and delaminate, what solutions are left, if any? (They only buy you time, and then the removal is much costlier).

I have spent most of my life working with coatings, paints, stains, glazes, etc. Industrial and residential painting, commercial coating, and restoration over 40 years of experience.

And here is where we are so far.

The best solution for replacing commercial roofs permanently, reducing costs dramatically,

and reducing interior building temperatures, is the installation of an Epoxy Cool Roof Systems

(ECRS). This highly reflective and emissive product (simply coat every 20 years and get a new

warranty, the original bond will not let go)is permanent and low VOC. The ECRS product fuses

with the roof surface, encapsulates and preserve your roof permanently thus saving you money

and keeping your roof and building cool during the hot months of the year.

An ECRS roof is a permanent roof over your existing roof creating a waterproof seamless

solvent based epoxy cool roof that is permanently bonded to your old roof. It will preserve your

roof forever. All you need to do is simply roll out 1 topcoat of epoxy every 20 years and wait

another 20 years and recoat. You will never have to tear off or replace your commercial roof

again, saving money now and more money in 20 to 25 years from now.

An ECRS permanently encapsulates the existing roof and anything underneath. Asbestos, heavy metals, and insulation less than R-30 or R-22, need not be touched. This eliminates the need to remove and incur the extra cost of asbestos cleanup or replacing the insulation. They are all undisturbed and encapsulated. Flashing and step flashing also remain as they are and are sealed with ECRS.

Low or No VOC Solvent based waterproof ECRS is a far better technology than rubber (EPDM), BUR, Tar, Asphalt or TPO and needs to only be re-coated every 20 years once roof is initially installed. Superior on metal roofs and concrete surfaces.

Roofs are seamless; ice and then water will not separate and penetrate.

No Tear-Off means: no risky exposure to the floors below or exposure to extra costs related to clean ups, asbestos clean ups and disposal, and insulation replacement costs.

ECRS provides the strongest bonded repairs in the business. Permanent bonding as well as cooling the areas that are tearing, less roof stretch on critical areas of existing roofs means less leaks.

Most Water based and silicone coatings only give you a 48 hour standing water guarantee…ECRS is 20 yr. standing water guarantee (originally developed for underwater steel girders).

Epoxy Cool Roof Surfaces also reduce interior building temperature. ECRS Prolongs HVAC systems by reducing work load and by reducing temperature on the roof. In one and two story buildings HVAC savings can be significant.

Rebates and Savings:

Because the ECRS saves energy, especially at the peak demand periods of the day, rebates as part of existing energy efficiency programs may be available. The first thing to do is contact the local utility, find out if rebates exist, and, if so, talk to the program manager about how a cool roof may fit into the framework.

“Rebates are mostly administered by utilities,” says Peter Turnbull, senior program manager at Pacific Gas and Electric and vice chair of the Cool Roof Rating Council (CRRC). “Go to them and ask how to apply.”

ECRS roof systems can be applied directly to existing roofs, saving expensive removal and disposal costs. The Permanent overlay roof system is a fully tax deductible operating expense. The systems also prolong the life of the roof indefinitely. Additionally, the reflective coating substantially cools the building, reducing the demand for electricity and A/C costs.

ECRS Roofing systems care be applied directly to existing roofs and the installation does not require any special equipment. ECRS roofing systems can be installed without any disturbance to building occupants. Meets V.O.C emissions regulations to eliminate facility downtime during application and any unforeseen costs such as asbestos removal that can occur during a tear off.

This is actually a game changer and a sustainably designed product. It eliminates the expensive cycle of: remove, replace repair, remove again, replace, repair, etc.…

Epoxy Cool Roof Systems.

Escoatlantic.com pyui@aol.com 443 553 5888 Paul E. Hughes