Eco-friendly Flameless (Cold Ply) Flat Roofing System

For over a century; flat roofing methodology has not changed that much. In the 1980’s, single ply membrane systems and torch applied modified bitumen assemblies were what fundamentally changed the market from traditional built up tar and gravel roofing systems.

Certain waterproofing methods like single ply membranes were slower to catch on than other conventional methods due to a lack of history in terms of reliability in the Canadian marketplace. After all, we are a conservative people when it comes to trying “new things”(Roofers that is to say). 

The fact is reputable roofers don’t like problems, call backs, or upset clients; so the proverbial “stick to what I know” appears to be the industry norm.

But every now and then, someone has to lead the way for others as the guinea pig to implement new technology or at least what the public may view as new technology.

What Is A Flameless (cold ply) Flat Roofing System?

Case in point is cold applied modified bitumen flat roofing systems. Such methods have been employed in Europe for over three decades. In Canada, such methods were relegated to projects for schools, hospitals, extended care facilities, and food processing plants, as examples of facilities requiring low odour, flameless roofing systems.

If you are a commercial flat roofing contractor today, you are faced with limited insurance syndicates that offer flame related insurance, and you will pay dearly for such coverage even without an incident. Have one or two smoke related or fire related claims and you will simply not get insurance.

That is the reality of today’s roofing industry and many homeowners, building owners and facility managers are not aware of it. That means in reality that two in ten roofing contractors today actually have the appropriate coverage for completing hot asphalt applied or torch applied roofing. This; as told to us, according to our insurance brokers.  An informal survey of associates in our industry leads me to conclude the information is true.

The good news is that flameless flat roofing is here, and is proven, and represents among the safest choices for both commercial and residential property owners.

One of the prior challenges with using cold-applied modified bitumen was temperature limitations when applying such materials. Soprema™; a leading and proven manufacturer of such products has developed winter grade adhesives which permits installations in colder temperatures (minus five degrees celsius).

Seams of the field sheets can be thermo-fused using a hot air welding machine. This also insures an even adhesion rate at this critical area.

From an environmental point of view; burning bitumen into the atmosphere is not ideal for the ozone. Applying modified bitumen using hot asphalt or installing conventional BUR roofing presents an increased level of pollution, and produces carcinogens which are not ideal for installer health over the long run.

From a safety point of view; reducing the risk of fire is a huge benefit. In Toronto, many homes are over a century old with dry timber construction. Many commercial roof substrates are built of wood, and the resulting possibility of fire damage, smoke damage, and resulting water damage from fire fighting efforts increases dramatically when using open flame roofing methods.

While these methods will not disappear soon; it will not be long before consumers will be forced to pay a higher premium for such work, because the pool of those insured to do such work is shrinking.

Although cold-applied method costs are slightly higher today as a result of increased material cost, we are confident in the belief that such methodology of hot-applied application will become fewer as the decade unfolds.

Cities like New York and Chicago have banned torch-applied roofing for the fact that they have a great deal of older housing stock, high-rise buildings, and congested roadways; all of which contribute to a fire fighting challenge.

Additionally; educated consumers are demanding products that offer lower VOC emissions.

Our company has made the decision to get on board with the inevitable. We have investigated the possibility for a few years, because it can be costly to switch gears, invest in training, and have assurance that the quality of product being supplied to our clients equals or exceeds the quality of what we have offered for over four decades.

As a result; homeowners, as well as medium-sized commercial/industrial facilities, will now benefit by having a safer flat roofing option; only previously well known and regarded by engineers, roofing consultants and large commercial/industrial stakeholders.

In fact, the OIRCA™ (Ontario Industrial Roofing Contractors Association) promotes the use of flameless roofing solutions, and discusses in their published work, that it is in fact the future of flat roofing in the province.

Manufacturer warranties on Colply™ systems by Soprema, are similar to torch applied modified bitumen systems that they manufacture. Therefore; consumers can be confident they are receiving a high quality product regardless of which option they select.

Steps To Install Flameless (cold ply) Flat Roofing System

Installation of a cold applied modified bitumen two ply system is completed as follows:

  • removal of the existing waterproofing system to expose the bare substrate (roof deck).
  • clean and prepare the deck surface to accept new materials.
  • install a manufacturer approved vapour retarder layer over the deck.
  • install thermal roof insulation (polyisocyanurate) over vapour retarder.
  • roll out base ply of modified bitumen material, and allow the product to relax.
  • re-roll the base ply, aligning the roll neatly.
  • pour a prescribed amount of the base ply adhesive, and trowel using a 1/2” notched trowel or squeegee; insuring an even and uniform coverage of the adhesive. (On larger projects; commercial adhesive spreaders are used).
  • using heavy rollers; smooth over the base ply of modified bitumen to provide for complete and proper adhesion and bonding of the two products.
  • overlapping seams in the rolls of the material are then robotically hot air welded using a Leister® type gun which is set to a particular temperature commensurate with external temperature conditions.
  • detail work such as base ply membrane flashings and target flashings can be applied using a hand held hot air welder.
  • the base ply should be allowed to cure before applying the second ply cap sheet, although once the base ply is installed the roof becomes water tight.
  • the process is then repeated when installing the granular surfaced cap sheet which forms the second and final ply of the assembly.
  • the key to a successful installation is insuring that the surfaces on which the material is being applied are dry and clean; free of moisture or dust.
  • critical application techniques are required at lap joints , drains, roof appliances, target flashing, and wall flashing details.

While the procedure is relatively simple to explain; successful installation relies on a skilled flat roofing team that can deal with the intricate roof details encountered on any roofing project.

Two ply modified bitumen systems have been a preferred choice for decades based on the fact that they offer a hearty two plies of protection, remain stable during thermal expansion and contraction and are proven to perform if installed to manufacturer guidelines.

Other flameless roofing solutions include TPO, PVC, and Elastomeric.

Clearly the future is now, and now is the time for the flat roofing community to educate and promote to the consumer a cleaner and safer option. Imagine the relief for property managers, facility owners and the typical homeowner; who can virtually eliminate the fear of their property burning down when under-taking a flat re-roofing  project.

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