Common Roofing Problems in Ontario

Leaks—in the roofing industry it's a bad word, and for the people who experience them, it's a real nightmare. Tracking and locating the source of roof leaks can be difficult if you don't know what to look for. Luckily for you there is Jackson Roofing! Our skilled roofers are some of the best in the industry at tracking, locating and stopping roof leaks.

Curb Repair

Much of our work entails repairing older roofs that are experiencing problems. This slideshow will outline our repair process for a leaking HVAC curb.

This curb is no longer in use and has been covered over, but unfortunately is leaking.

For this repair we will be using grey 2Ply Modified Bitumen. One of the benefits of 2Ply vs. 4Ply tar and gravel is its ease of use.

Instead of having to carry up multiple pails of hot tar and lug a mop around, we choose to use this method.

First, the area is swept back and the gravel is chipped down to the existing 4Ply Membrane. This picture was taken between the sweeping and the roof has yet to be chipped.

Asphalt primer

Next, the field is primed with asphalt primer. Here we are installing the base sheet.

Base sheet is installed

After the base sheet is installed over the field and around the box, the cap sheet is installed on the field first and then around the curb. This picture shows us installing the wall flashings around the curb.


Once the outer perimeter of the patch has been sealed it is then coated with a layer of hot tar and embedded with gravel to complete the field. This picture shows that step already completed and us installing the final piece of capping on top of the curb.

Complete patch

Here is the complete patch. Because we used a 2Ply Modified Bitumen membrane on this repair, we do not need to cover it with gravel to complete it.


As unfortunate as it is, there are companies out there that will take advantage of a client's unfamiliarity with proper roofing techniques. Here at Jackson Roofing & Son Contracting Inc., we strive to educate our customers on the right way to install different roofing materials. The following pictures are examples of some improperly installed 2Ply Modified Bitumen Membranes.

2Ply Membranes

2Ply Membranes rely on a system of staggered edges around the perimeter of walls and curbs.

Base field

First the base sheet is installed on the field (horizontal), and then it is followed with a wall ply of base installed on the wall and extending 4" onto the field over top of the field base.

4" on the field to up-and-over the parapet wall.

Base wall flashings should normally go from 4" on the field to up-and-over the parapet wall.

First the base sheet is installed on the field (horizontal), and then it is followed with a wall ply of base installed on the wall and extending 4" onto the field over top of the field base.

Flat Roof

The entire process is repeated with the cap sheet then being installed on the field and covers over the 4" overlap. Then a wall ply of cap is placed over top of the field cap.

It's this "weaving" of overlaps that keeps the walls strong and stops them from pulling off and causing leaks like this.

2Ply Modified Bitumen Membrane

This is what a properly installed 2Ply Modified Bitumen Membrane should look like. 

Notice that the seams of the wall plies are staggered from those of the field to ensure the least possibility of water travelling along them.

Existing sheet metal flashings

Here the contractor has disregarded all rules associated with proper torching procedures.

They have taken their field roll and brought it right up the wall, not even taking the time to remove the existing sheet metal flashings.

Roofing membrane

The roofing membrane begins to wrinkle and warp as the expansion and contraction of the building (this happens due to weather changes) begin to pull the membrane off the walls.


Here the contractor attempted to re-roof this curb. Unfortunately for the customer, the attempt failed.

It pains us to see this lack of quality being passed off as roofing. If you have concerns that your roofing work is not being installed with the highest standards it is your responsibility to investigate.