Pros and Cons of Different Flat Roof Systems

General Roofing Systems Canada Repairs flat roofs throughout Canada. Flat Roof Repair; Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.

Below you will find the pros and cons of each type of flat roofing system we offer written by our Alberta roofing repair crew. A link has also been provided below to our main website describing each.

Spray Foam

While moderately low in price, this is largely based only on individual perceptions. As far as material efficacy goes, spray foam is seamless and light. However, in Canadian weather, it is subject to cracking due to extreme hot/cold shifts, and a failure can result in a complete re-roofing being required. As well, maintenance mandates top-coating, which contributes to expenses – nullifying perceptions about spray foam being a low cost solution.

Single-ply Systems (EPDM/PVC/TPO)

While these have been excellent systems in terms of performance and a lower initial price, they do not have the longevity of 4-ply tar and gravel or 4-ply liquid rubber. As well, these systems are vulnerable to tearing over time. The installation process also entails using mechanical fasteners, which provides another damage vector with respect to water and strong weather conditions.

Tar and Gravel

A seamless and versatile system, which also has a long life if maintained properly. However, the installation process can be quite messy. As far as maintenance goes, leaks can be difficult to find. As a result, maintenance costs are higher than single-ply systems and liquid rubber application. Maintenance or repair with tar and gravel systems often entails a vacuuming as well if damaged sites are difficult to locate.

SBS Torch-on

This system is lighter than 4-ply and has a broad range of application methods. However, torching is not seamless and the life cycle is shorter than 4-ply systems. A fire watch is also required during installation, which contributes to a higher price point.

Liquid Rubber

Seamless, UV stable, and elastic, this is a system which we have had a lot of success with in the Canadian climate. The 1000% expansion rate provides a “cushion” for extreme weather changes, which makes it resilient to tearing and leaks. The system is also multi-purpose, having applications in gutters, too. However, the price point is initially higher. In terms of total life cycle cost, it is similar to all other systems.


We usually recommend single-ply systems and liquid rubber to our clients. Single-ply systems are more economical on the front-end and perform well. Liquid rubber also has the least chance of failure, as it is the most predictable and is 4-ply. Also, it is the system most suited to Canadian weather due to its elasticity.

For more information about each system we have described, visit our main site by clicking here for more information on flat roofing.

Contact Us:
General Roofing Systems Canada (GRS)

24 Hour Emergency Roof Repair: Call +1.877.497.3528 toll-free.

British Columbia | Alberta | Saskatchewan | Manitoba | Ontario

Emergency Roof Repair Situations

General Roofing Systems Canada provides roof repairs throughout Canada. Roof Repairs are completed in the following cities; Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.

Emergency Roofing Repairs

Wind Warnings and Torrential RainFall has been causing roof failures in British Columbia, while meanwhile in Southern Alberta high Winds are Blowing Shingles, Shakes, and Tiles off Roofs Again.

This week has been tough on roof systems from the West Coast all the way to Saskatchewan. Our call center has been over-whelmed with wind related roofing repairs calls along the West Coast including Victoria, Vancouver Island, Vancouver, Vancouver North Shore, and in the Fraser Valley. While in Southern Alberta such areas like Lethbridge, Medicine Hat, Okotoks, and even into Calgary have been experiencing wind gusts of up to 120 km/h.

The unusual high winds have been tearing shingles off roofs and causing general havoc with a variety of roofs types. We have received calls with complaints of skylights blowing off or leaking, roof vents, flashing, and even roof hatches needing repair.

With the heavy rain on the West Coast, this has caused flat roofs to fail, this particularly has applied to those that have drainage issues or drains that are plugged. With the cycles of having warm air thawing to only freeze again due to the Chinooks in areas like Calgary, AB, this has been resulted in our 24 Hour Toll Free Emergency Roof Repair line to receive several repair calls.

We are finding that Roofs with improper attic ventilation are having condensation issues to areas even as far north as Edmonton and flat roofs are requiring more maintenance to clear drains that are freezing over with ice.

Solutions for Roof Repairs, Attic Condensation, and Roof Drainage Issues

There are some solutions we can offer to help with the various problems roofs have this time of year. However If you cannot solve the repair or maintenance issue by yourself, call our 24 hour emergency roof repair toll free number at 1.877.497.3528 and schedule a repair person to attend.

Flat Roof Membranes
Repair Crew Fixing Flat Roof Connected to an Industrial Metal Roof

Flat Roof Drainage Problems: Flat roofs unfortunately do require some regular maintenance, especially in high winds and freeze-thaw cycles.

Roof Drainage: The roof drains are prone to clog from leaves, tree branches, and with the ice and snow melting and freezing on the roof. Drainage problems on flat roofs can also be compounded by an inadequate slope of the roof. Nonetheless, a spring and fall maintenance of the roof is key to ensuring the roof bears well during bad weather. Click here to see our  Flat Roof Maintenance check list.

Roof Inspection: Extreme winds, heavy rain-fall, and snow and ice melting should trigger an inspections to be completed. It is preferable that this is completed during the storms to ensure our technician’s ability to see if the roof drains are clear.

Roof Slope Problems: With improperly sloped flat roof systems, there are solutions to mitigate these issues. An improper roof slope can be examined with our technician at the time of inspection or while we are performing maintenance to your roof.

Condensation in Attic Spaces

Roof Sheeting Mold, Attic Mold, Condensation II
Condensation in Attic Space

Sloped or Pitched Roof Attic Condensation Problems Attic condensation repairs or remediation tend to be a more involved process requiring a number of steps.

Solving Attic Condensation

Your attic require proper ventilation. You need to check the intake air typically at the roof soffits to be sure that there is enough air coming in to your attic space. Be sure to check that insulation is not covering the air from entering your attic by following the air flow along the roof sheathing to where you come to the ridge or peak of the roof.

Check the exhaust vents (typically by each square foot or along the ridge) to be sure they are not plugged with snow and see if there are enough roof vents. You will need about 1 square foot of roof venting per 100 – 300 square feet of attic. A calculation commonly used by our roofers for attic / roof ventilation is 1:250. If the air vents exhausting the intake air is appropriate then you need to check the vapor barrier of the attic. It cannot be compromised and be letting warm air in.

Warm air rises through the attic into the roof sheathing. The snow on the roof then melts and creates ice dams. The ice dams then back up under shingles, shakes, and tiles causing leaks in to attics and then ultimately in to your house through the ceiling. If none of these problems can be found in your attic, it is best for you to then call the experts.

Shingles Torn off in winds

Wind Blows Shingles off Improperly Installed Shingle Roof in Calgary
Shingles Torn off in Winds

High Wind damage and Roof Repairs to Shingles, Tiles, and Shakes Repairing Damaged Roofs: Ultimately, after the installation of shingles, tiles, or shakes are complete and the winds begin to increase, you can now face blow-off problems. The best we can do is repair the windblown damaged roof.

How to Shingle a Roof: Prior to having your roof replaced, it is a good idea to know the specifications and the proper way to shingle a roof to ensure your roofing contractor is in check at time a roof replacement is required. Our website has a series on How to Shingle a Roof that explains the process of shingling for areas with high winds and how to avoid costly repairs due to wind damage.

Roof Underlay: Beyond the actual installation principles when replacing your shingles, shakes, or tiles there is the issue of the roof underlay. If the proper roof underlay is used and is installed correctly, then one does not have a concern in regards to shingles, shakes, or tiles being blown off. The roof underlay or membrane will keep the roof water-tight with-out the shingles so no leaks occur.

Shingles for High Winds: Finally, there are roofing shingles available that are designed to withstand high winds. Shingles like the Malarkey Legacy have high wind ratings of up to 170KM per HR which gives areas like the West Coast, North Shore of Vancouver, Calgary, Lethbridge etc. some advantage over the winds that damage roofs every year.
Should you have any questions or concerns regarding your roof, our office is always able to provide over the phone advice, set up inspections or arrange for a complete repair.

Until Next Time,

The Team at GRS

General Roofing Systems Canada (GRS)
24 Hour Emergency Roof Repair: Call +1.877.497.3528 toll-free.

Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.

Low Slope Roofing- Choosing the Right Flat Roof Membrane

General Roofing Systems Canada provides low slope installations throughout Canada. Low slope installations are completed in the following cities; Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario

The inquiry below came in to our call center today, we thought it best to post it as an article to our blog to assist others who have questions regarding Low Slope Roof Membranes.

The email conversation below contains standard questions and answers that our clients have when choosing the correct “low slope roofing” or “flat roof membranes”.

The following items are a listing of the topics covered amongst the email; low slope roof life cycle costs, choosing the right roofing contractor, low slope roof prices, roof installation quality, choosing the right flat roof membrane, differences between various flat roof systems, and many more.

RE: A roofers perspective of low slope / flat roof costs, life cycle costs, torch down 2difference between flat roof systems, and most importantly  roof craftsmanship.

Email Conversation:


I am presently in the middle of preparing to build a new office space with a low slope. My architect was advising the TPO material for it being more “green” and its heat reflection.

 However,in my internet search, the results and outlook for TPO roofs is still in question. I am looking towards the old standby 2 ply SBS and I writing this letter to you as you do all these products.

 Which one would last longer and what is the cost difference between the 2 products… also include PVC if you can.



Dear valued client;

Thank you for your inquiry.

We have been receiving a lot of the same sort of inquiry lately (what are the cost of flat roofs, the life cycle cost of flat or low slope roofing, and the difference between low slope or flat roof membranes).

Generally we tend to receive these types of inquiries at this time of year, this is primarily due to commercial, industrial and home owners having time to complete research as a result of the holiday season.

With saying that, I am going to post your questions about low slope roofing to our blog along with my answers (in article form) so that our conversation(s) will assist others when researching about low slope roof membranes and roofing contractors.

Your “Roof Life Cycle Cost” will be determined as follows: 90% will be a result of the roof installation quality and 10% will be determined from which low slope roof membrane is selected.

For every ten hours you put in planning for your new flat roof, nine of those ten hours should be researching and selecting the right contractor for your project. If you put in a total of 5 hours planning your flat roof project, 30 minutes should be spent considering the different flat roof membranes available and 4.5 hours should be spent researching, selecting, and communicating with your new flat roofing contractor.

The most important aspects to considering a Flat Roofing Contractors is; Roof Workmanship Quality, WCB, BBB reports, Insurance, Liability, Warranty, Guarantee, Safety programs. Although it is not necessary that the flat roofer is a member of the BBB because complaints can be lodged whether a company is a member or not.

Random consumer complaints are not that important due to the fact that anyone can rant about anything online (It is impossible to make everyone happy 100% all the time), yet complaints to the BBB should be given serious consideration as the BBB has a highly professional process required for authenticating complaints.

The workmanship guarantee is to be considered one of the greatest factors to take into consideration.  In some ways this is even more important than the roof membrane manufacturer warranty.

Alongside this there are other considerations to keep in mind such as insurance coverages for example:

A) Work Safe / WCB clearances (you are able to get one from Worksafe / WCB),

B) Commercial Liability Insurance (which should be 5,000,000.00 – some go as low as having only 2,000,000.00 insurance),

C) Roofing Contractor’s Safety Program (which ensures the workers are actually being safe while on your site including the use of hard hats, vests, harnesses, daily hazard assessments etc.)

These are all important considerations that help protect the customers. An injury to a worker can be a significant issue for a home or business owner if the roofing contractor has not followed the proper compliance procedures. Such an event like this can cause you considerable expense and aggravation.

TPO Roof Life Cycle Costs

Now in regards to your question pertaining to TPO Roofing and life cycle costs, unfortunately this is still unknown. Perhaps not scientifically, but from a flat roof installer perspective it is.

Statistically speaking, we have more data specified to PVC roofs than we do TPO. The reality is that all low slope roof membranes have similar life cycle costs. Yet when you consider them statistically or scientifically they do vary, but all in all, low slope or flat roof membranes all perform quite well.

However, coming from a “roofer’s perspective”, here is what I can tell you; An issue that we as roofers see every day on the roofs, which in truth should be your highest priority in research is the actual installation of the material itself. Numerous building and home owners alike are unaware of the actual process, procedures and potential roof failures due to improper installation of the flat roof.

Another area of concern is the other workers that will attend the roof during construction or after, such as HVAC installers for an HVAC retro-fitter.

Now with the assumption that the contractor is reliable and adheres to all the proper regulation, the reality is that things can happen when a flat roofs are being installed. No company is flawless and has a perfect flat roof installation every-time.

In the offices, we here several conversations about how things can and do go wrong, yet it is how we deal with the problem that separates us from success or failure with other roofing contractors. We see time and time again, people that do not do their proper due diligence because they assume things should just go without incident. Although this is not like buying a car. Hiring a trade is much different.

Of course on the other side of managing roofers or the installation of flat roofs is that there is the pro-active side of things that says there are things that we can do as the roofing contractors before problems arise to assist in a higher probability of a proper roof installation occurring.

Now, in our instance we have done things like institute our industry with an Unconditional Lifetime Guarantee which causes our roofing staff to be more aware of the day-to-day incidents that could occur. It is our responsibility to provide superior roof craftsmanship. This has our staff in a more stringent project path for a flat roof installation quality control system. Ultimately, the craftsmanship itself is what most determines the true cost of your flat roof and not which flat roof membrane or flat roof system was chosen.

Once you get past the issue of the quality of installation for your roof and hiring the right contractor you can then consider which roof membrane to use.

Now to provide some answers specific to your questions, here are some considerations for your low slope roof membrane research;


With respect to traditional low slope roofing (SBS, TPO, PVC, EPDM, BUR) I would recommend using 2 ply SBS modified with complete confidence.

The reason is that with a single ply, you have opportunity for what we call catastrophic Failure. In other words, a hole the size of a quarter in the membrane can cause significant damage to the complete system as the water can travel. With SBS, it is torched down and the opportunity for water migration is less. Here’s one other factor to consider with SBS modified, if you have roof installer that does not install the membrane correctly, this will result in you having significant issues. The deficiency list can be considerable and cost more than replacing the roof in the first place.

Now, You didn’t ask about multi-ply low slope roofing specifically, yet I am going to take the liberty of giving you a couple of thoughts regarding those systems. You are able to get a multi-ply low slope roof like the Tough Roof System that will give you the reflective values you desire. Additionally, you will get the sense of security knowing your roof will have maintained durability. The Tough Roof is a multi-ply built up (BUR) roof system that has layers of bitumen (in this case a synthetic layer in between instead of the traditional felt mats between each layer) and on the top, Tough Roof uses white elastomeric roof coating which contributes to the reflective component.

The other option you have in these newer systems is a multi-ply liquid rubber system which is VOC free, completely environmentally friendly and you can cover it with an acrylic reflective top coat. The system is a proprietary system from General Roofing that includes 2-4 layers of liquid rubber with a synthetic fabric between layers of built up and with an optional top coat of acrylic reflective roof coating. Of all the systems you can get, this particular system is most environmentally friendly, it is bullet proof like the built up roofs, and it can be as reflective as you choose.

So ultimately your choices are; traditional 3-4 layer built up roofing (Tar and Gravel) which is 3-4 layers of tar with tar felt paper in between, then the 2 ply modified bitumen which is torched down, the single ply roofing (EPDM, TPO, PVC) which is mechanically fastened, fully adhered, or ballasted, and then the newer type of built up roof like the Tough Roof which is 3-4 ply of tar with synthetic fabric between the layers with an elastomeric top coat for reflectivity and the newer built up liquid rubber systems from GRS that are 2-4 layers of built up liquid rubber with a synthetic fabric between the layers with the option of a reflective top coat of acrylic elastomeric roof coating.

From least expensive to most expensive the roof membrane systems typically go from least expensive to most costly as follows; Spray Foam, EPDM, TPO, PVC, 2 Ply, GRS Liquid Rubber BUR, Traditional BUR, Tough Roof. However, it is important to note when considering the cost of a flat roof or a low slope roof system two things. First, the cost difference between flat roof systems as you go from one to the next is small in comparison to expected life cycle cost planning. For example, EPDM roofing is moderately more costly than Spray Foam, and PVC moderately more cost than TPO and on and on as you go through each system. Yet the important consideration is the cost of the roof over a period of time. A properly installed Tar and Gravel roof or properly installed 2 Ply SBS Torch on Roof will likely last much longer than EPDM, TPO, or even PVC – “likely” has a number of considerations…. weather, application, service workers on the roof, etc. And a Liquid Rubber Built Up Roof and the Tough Roof built up systems have almost unlimited life cycle as they both come with maintenance agreements to renew the top reflective layer of elastomeric coating.

I hope this has helped answer your questions, please feel free to contact us any time should you require more information or would like to ask us more questions.

Until next time

The staff at GRS


General Roofing Systems Canada (GRS)
24 Hour Emergency Roof Repair: Call +1.877.497.3528 toll-free. Email

Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.


Flat Roof Membranes: Sample Customer Query

Below you will find a customer inquiry we had in Fall 2011 referencing flat roof membranes for a new inner-city home our customer is having constructed in Calgary, Alberta.

This fellow was the unfortunate recipient of what occurs in the flat roofing industry every year – there is a year-end tsunami we as roofers experience when panicking clients need to have their flat roofing systems maintained, replaced, or repaired. It turns into an “all hands on deck” period of time during this so-called tsunami, especially for our commercial roof and industrial roof clients. This particular flat roof membrane query unfortunately took some time to return, but the client was gracious nonetheless. Please note that the quoted blocks in italics are our responses to the client’s questions.

< Start of Email >

Well thank you very much for the in-depth follow-up, it is much appreciated.
I do have several questions, some of which may overlap with others. Please bear with me, my inexperience with flat-roofing necessitates a bit more research, and there seem to be so many systems that it is difficult to know which is more appropriate than the next.
1. With the liquid rubber roof coating system, will the membrane simply seal around any punctures in the roof (i.e. irrigation line for the planter box, roof skylight openings, scuppers in the parapet), or does this require separate attention?
Liquid Rubber roofing, at least the specification GRS applies liquid rubber roof coating to is a process of steps. The first being cleaning the substrate or roof deck, next is preparing all roof penetrations, fasteners, expansion joints, connections, etc with a scrim fabric sheet (polyester woven scrims) and trowel grade liquid rubber (done by hand with trowel, squeegees, and rollers), then a flood coat of liquid rubber (sprayed), and then the final stage of liquid rubber roof application is a final spray coat of liquid rubber. Another coat is optional to add colour. This is done with an acrylic top coat. The liquid spray on acrylic roof coat can be specifically tinted to the desired color.
2. Do you recommend, as per the liquid rubber system, a 2-layer approach (using the Sealroof A-100 over top the Sealroof B-200), in the same way you would do a 2 or 3-layer torch on system? In this way, you could apply a white top-coat < GAF Top Coat > to help reduce the heat island effect on the roof and help alleviate the temperature variation in Calgary?
The GRS process of application for liquid rubber roofing, flat roofing, and pitched roofing is typically more involved than most specifications our roofers see day-to-day in the marketplace. Specific to Liquid Rubber roofing, our system of application is detailed at point 1 above. Top coating the liquid rubber is also detailed above and there is an article linked to our website specific to the white and black decision with flat roof membranes found here (Carlisle-Syntec Article).
3. My current details include a sloped insulation for added R-value, over top of a ventilated ceiling cavity with vents in the parapet wall. Who do you get your sloped insulation from, and is it custom made for the project, or does it require labour to adjust it? Is it possible to simply install sleepers above the roof joists to achieve slope and sheath the roof and apply the membrane overtop of that, and sacrifice the added R-value of the sloped insulation? Is that normal?
Sloped insulation for flat roof structures is a common method. Many designers will specify the framing of the substrate to be sloped also as an alternative. We source our sloped roof insulation from a number of companies. One we often use in your area is Plasti-Fab. It is a pre-engineered sloped insulation that is delivered with a diagram for installation. We would have difficulty answering to the roof sleepers question until on site or more discussion was had.
4. You mentioned custom metal flashings, and I am wondering what the scope of your roofing will entail (in other words, do you also provide flashing around skylights, and around scupper holes for drainage)?
Various roof flashing required we provide to our flat roof customers. Typically, roof skylights will have flashing kits, but various designs will have us custom fabricating metal. Whether it is flat roof cap flashing, cant flashing, edge flashing, or various custom flashing for roof membranes… we fabricate and install it.
5. You mentioned the TPO system (which I have been recommended to use from a colleague) is more suited for Vancouver than for Calgary. What are the reasons for this? Is it strictly based on freeze/thaw considerations or total precipitation, snow loads, or some other reason? One of my biggest concerns is that the roof membrane will not stand up to the temperature differentials we all know that Calgary is susceptible to.
Answering to the environmental impact to various roof membranes (such as freeze thaw) is a complicated topic. SBS Modified Bitumen (torch on) and Built Up Roofing (Tar and Gravel) has been a mainstay for so long, with Alberta holding to it longer than most other areas of the world. My comment to TPO or any roof membrane that is reflective or light colored is more specific to the energy efficiency of roofing systems or flat roof membranes. In Alberta, many see it as counter productive to have a reflective roof as more often than not we have our heat on than we do the air conditioning. This too is a diverse conversation. Our web site under the flat roofing section on the right column has links to articles. With respect to how each membrane will hold up specific to Calgary, that is a difficult question. TPO, PVC, EPDM single ply flat roof membranes are being installed every day in Calgary, as are the traditional SBS modified and BUR flat roof membranes. SPF – Spray Foam Roofing is another roof membrane option and then the Liquid Rubber roof membranes. At issue is that most roof membranes have not been installed for a long enough duration in the Calgary market for an excellent evaluation of performance. For example, the liquid rubber we are referring to in this instance has only been available for shy of a decade and not widely used until very recently. Our comfort is in that we simply add more liquid rubber membrane if there were to be failures. When single ply membranes were first introduced the remediation of early failures in the membrane was much more complicated than with liquid rubber roof membranes – with liquid rubber we simply apply more liquid rubber if failures were to occur. In saying all of that, we have significant liquid rubber roof membrane applied over the last 3 years with no failure to date.
6. Is a Torch on SBS system the only one which requires a ballast? Or does the liquid rubber also require a covering to reduce UV penetration, etc? Would adding Ballast prolong the life of some of these other systems?
Ballasting a roof membrane is for the purpose of keeping the roof membrane to the roof deck – wind uplift etc. For example, a ballasted EPDM roof membrane holds the EPDM down so the wind doesn’t take the membrane away. The EPDM is adhered at the seams and loose laid to the insulation or roof deck with the roof ballast (rock) covering the membrane. Inverted loos laid systems have the roof insulation laid on top of the EPDM roof membrane with the rock or roof ballast on top of the insulation. Single ply roof membranes (EPDM, TPO, PVC) can be mechanically fastened (not requiring roof membrane ballast), Loose Laid (requiring roof membrane ballast), or Fully Adhered (not requiring roof membrane ballast). With SBS Modified Torch on roofing their is no ballast required as the SBS membrane is torched or fastened to the system by way of torching or with adhesives etc. The UV is not an issue also with SBS Modified Roof Membranes as the cap sheet (or second layer of roof membrane) has granules attached that keep UV away from the Bitumen. With Built Up Roof Membranes (or BUR) the layers of bitumen are covered with an inset top layer of gravel to keep the UV away from the bitumen in the roof membranes (typically a four layer membrane system). The gravel in this instance is not for ballasting, it is only for the purpose of UV resistance. In the case of Liquid Rubber Roof Membranes, the liquid rubber manufacturers claim UV resistance with-out the requirement of granules as with SBS membranes or gravel as with BUR or Built Up Roof Membranes.
7. Do you have specific price per square foot values for each of these products, or is the quote system more complex than that (in terms of metal flashing, scupper detailing, etc.)?
Specific pricing for flat roof membranes is wisely derived after review of the construction drawings and discussion with the parties that can affect construction processes. In your instance, specific pricing for the various roof membranes can be accomplished by way of the construction drawings provided.
It seems from your email that the liquid rubber system is more costly initially and less costly over the lifespan of the roof. Can you list the roof systems according to their initial cost for installation? I am very interested in the liquid rubber system, but a little hesitant regarding the price. My understanding was that a modified Torch-on SBS was cheaper than some of the other systems, like a TPO membrane or a soprema system.
Pricing for all flat roof membrane systems are similar. Tar and Gravel Roof membranes (or BUR) will tend to be more costly due to the extensive labour, SBS Modified should be similar or perhaps a touch more than the Single Ply roof membranes (TPO, PVC, EPDM), TOUGH ROOF (which is a concept built on the strength of the traditional Built Up Flat Roof with an elastomeric top coat) would be on the higher side of the pack, and Liquid Rubber systems (if done per the specification of membrane application that we use) will be in line with Single Ply. More often than not, with roof membrane choices and pricing, you will receive varying opinions that are usually specific to what the roof membrane applicator installs most, what roof membrane the roofer is certified to install, etc. The widest divergence we see in flat roof membrane pricing is not necessarily the roof membrane material that will be used, but the process of application of the roof membrane itself and whether the flat roofing company has all the other operating costs that credible flat roof companies can have due to safety, staff remittances, benefits, company vehicles, licensing, insurances, etc.
My roof works out to be about 1150 sq. ft. (inside parapet), with the planter on the second storey being about 23 sq. ft. Would you be able to work out a few prices using the Torch-on SBS, liquid rubber, EPDM, and Soprema systems that you install?
As it applies to SBS Modified, we typically use when available to us the IKO SBS Modified Bitumen products vs Soprema. Not that we see IKO superior, it is just what our company typically uses for SBS roof membrane unless specified otherwise. I am personally a Soprema certified installer and I don’t see much of a difference either way – both IKO and Soperma produce a quality SBS Modified Roof Membrane as I see it. With EPDM, we regularly install Firestone and Mulehide EPDM (I believe Carlisle manufacturers the Mulehide EPDM, but I could be wrong). With TPO we install Firestone and Mulehide regularly also. Liquid Rubber roof membranes come in various forms, because we are installing so much of the liquid rubber roof membranes we have various specifications for application and material for the membranes. I will price yours specific to how we see it best applied and according to the manufacturer(s) we see as best for your roof membrane.
The pricing for the various roof membranes I will forward in a separate email.
Thanks again for your comprehensive response. You’ve been most helpful.
< End of Email >
Contact Us:
General Roofing Systems Canada (GRS)

24 Hour Emergency Roof Repair: Call +1.877.497.3528 toll-free.

Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Canmore, Lethbridge, Medicine Hat, Vancouver, Whistler, Cranbrook, Saskatoon, Regina, Winnipeg, Toronto and all points between. British Columbia, Alberta, Saskatchewan, Manitoba, Ontario.

Roof Replacement Problems

General Roofing Systems Canada provides roof replacements throughout Canada. Roof replacements are completed in the following cities: Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.

Below is an article describing the troubles that can arise with any and all roofing situations should you have with work completed improperly.
We know that every trade has its problems. Poor installations, normal deficiencies that occur, and then unprofessional workers. Unfortunately, the flat roofing trade is no exception to such occurrences.
The new home in this flat roof inspection report completed by our roofers yesterday is a victim of the exact problems mentioned above. The home in the below pictures is quite new and  was architecturally designed. However, the roof was installed poorly (2 Ply SBS Modified Bitumen) resulting in leakage. We suspect this flat roof has been leaking every time it rains or snows since it was first built.
As a result of this poor installation, the homeowners will now have to face extra costs in order to replace it all together.

Initial Inquiry:

We are looking for a replacement quote. needs repairs for torch on flat roof, client requires  the roof replacement completed within 2 weeks. Highest section of house is leaking and flat roof installed incorrectly.  Flat roof seams aren’t sealed.

Field Report, July 27 2011:

The upper smaller flat roof (SBS Modified Bitumen) on this home is completely past the point of return and a roof replacement is required . All the roof membrane seams are lifting and there is no bleed out at the membrane seams. All termination points along perimeter of the flat roof are not torched down properly. All intersections are lifting and there is no slope of roof toward scuppers. The upper roof needs to be replaced completely and should be ripped down to the deck.  It also requires a cricket (slope towards roof scuppers).

The Lower canopy roof (Modified SBS Torch On) over the main entrance of the home is in the same state as the top roof.  The roof is not torched properly, it also slopes down toward house instead of away from.  There is only one roof scupper at the high point of the roof corner which is not draining. The drainage on this roof system is very poor. The lower roof needs another scupper and or a drain in the North corner, this also needs to slope away from the house. I recommend another rip and a full roof replacement to this section also. In order to replace the roof systems we will need to take all cap and detail metal off  as it is tied into the stucco!

Flat Roof Replacement – Pictures of Flat Roof


Flat Roof
Cap Flashing

Flat Roof Houses

Flat Roof Metal

Flat Roof Needs to Be Replaced

Flat Roof Inspection

Flat Roof Repair

Flat Roof Replacement

Flat Roof

Flat Roof

Flat Roofing Repairs

Residential Flat Roofing

Until next time,

The Team at GRS

General Roofing Systems Canada (GRS)
24 Hour Emergency Roof Repair: Call +1.877.497.3528 toll-free.

Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.

Commercial Roofing

General Roofing Systems Canada performs commercial Roof replacements throughout Canada. Commercial Roof Replacement: Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.

Commercial Roof Replacement – Trucks are unloaded and materials brought to the roof.

Commercial Roof, Insulation for Flat Roof2
Commercial Roofing: 1.877.497.3528 | General Roofing Systems Canada

With the temperatures in Edmonton, Alberta being close to 30 degrees, our commercial crews were faced with the challenging task of having to unload several materials onto a roof in busy downtown. This task was exceptionally strenuous due to the heavy/large capacity of materials such as; engineered sloped insulation and craning flat roof materials.

Commercial Roofing2
Commercial Roof Insulation

Our crews had to shut down and block off a section of the downtown core due to requiring; two sloped insulation semi-trucks, one crane and another large semi that held the extra materials. Despite the chaos of the job, our Crews were able to complete the task within a short time span. The commercial roof that the materials were loaded onto, is now ready for replacement. Over the next month one will be able to notice the transformation taking place.

Due to the extreme heat several roofing crews along with GRS’s, were ending shifts early. When the temperatures are close to 30 degrees on the ground level, you can almost guarantee that the temperatures on the roof will be closer to 50 degrees, if not higher.

This will be an ongoing project with GRS, We hope to post pictures soon as the job progresses.

Commercial Roofing / Flat Roofing – Our Web & Blog Links:

Until next time,

The Team at GRS

General Roofing Systems Canada (GRS)
24 Hour Emergency Roof Repair: Call +1.877.497.3528 toll-free.

Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.

Information Guide for Flat Roof Replacements

Flat Roof Membranes, Flat Roofing Systems, Flat Roof Repairs, Flat Roof Maintenance, Flat Roof Energy Efficiency, Flat Roof Coatings, Flat Roof Replacement.

The time of year has come again when we get a lot of calls about flat roofing. Flat roof repairs, flat roof system choices, flat roof membranes, and how to maintain a flat roof.

We thought it would be convenient for our customers to provide a flat roof link page on flat roofing to give a good launch page for flat roofing and all the options available.

Flat Roofing System and Membrane Manufacturers:

IKO, Soprema, Genflex, Firestone, Mulehide, Carlisle, Siplast

Flat Roof System and Membrane Choices
Details all of the options available for flat roofing including BUR, Tar and Gravel, EPDM, TPO, PVC, Spray On Foam, Emulsions, Roof Coatings, etc.

Flat Roof Coatings
Details all of the options for coating metal and flat roofs including Elastomeric Coatings, EPDM Coatings, Polymers, Mastics, Etc.

Energy Efficient Flat Roofing
Carlisle-Syntec PDF paper on “Energy Efficient Flat Roofing – More Than a Simple Black and White Issue”.

Flat Roof Maintenance and Flat Roof Repairs
Details all of the flat roof repair and flat roof maintenance considerations.

Commercial Flat Roof Replacement
The due diligence process of Commercial Roof Replacement.

Flat Roof Replacement
The process of flat roof replacement.

Consideration Prior to Choosing to Replace Your Flat Roof
Wind uplift considerations, R Values, moisture in the existing flat roof system etc.

Choosing a Flat Roofing Contractor
The due dilligence process of engaging a Flat Roofing Contractor.

We trust our consolidated link listing resource on flat roofing will assist you and save our customers valuable time.

Until next time,

The Team at GRS

About Us

General Roofing Systems Canada is a Comprehensive Building Envelope and Roofing Contractor serving Western Canada. Calgary, Red Deer, Edmonton, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Kelowna, Vancouver, Whistler, and points between.

Contact Us

Calgary, Alberta

Mail to:

240 – 70 Shawville Blvd. SE
Suite 1460
Calgary, Alberta Canada

T2Y 2Z3

+1.877.497.3528 Toll Free

+1.403.873.7663 Service

Edmonton, Alberta

Mail to:
3428 99 Street NW
Edmonton, Alberta Canada

+1.780.424.7663 Service

+1.877.497.3528 Toll Free

Vancouver, British Columbia

Mail to:

1489 Marine Drive
West Vancouver, BC Canada
V7T 1B8

+1.604.261.7663 Service

+1.877.497.3528 Toll Free