Finding leaks on tar and gravel roofs is not an exact science. But once you have found them what is the next step? In most cases it is raining out or the roof is wet so you can’t put down a permanent patch. That means you have to put something onto the split or roof hole that will stop the leak and works on wet surfaces. The two most common tricks of the trade are either using a Portland cement or a Bentonite clay mixture. I choose the clay. Here’s why. They both stop the leak initially. But the cement forms and solidifies into a clump that does not change shape. So once it’s formed it stays that way. The problem being is that when it completely dries it releases it’s grip in the roof and becomes separate. Thus the leak or roof deficiency is now open again and prone to further leakage… Except it’s got a clump of cement over top of it! The clay works differently. It too does dry and somewhat release it’s grip on the roof over time but it reactivates with the next rain and turns back into the thick slurry that stopped the leak the first time. Essentially it is reusable on the same leak. But to be completely honest… you need to get that roof leak upgraded to a permanent patch as soon as possible. Don’t leave the temp patch on too long and test it’s performance abilities. We dropped some clay on a roof leak in Richmond and also in Burnaby today. This is what it looked like.
You know you have a roofing issue when the roof has “caved-in”. That’s what I saw today in Vancouver. Now this just didn’t happen over night either. This has been progressing for a couple years. There has to have been some clues about what was going on overhead. When not heeded, the costs can mount.
Preventative maintenance might have nipped this in the bud.
It is what it is. Now the gutter and drains are the most critical areas of the roof because that’s where all the water goes. Our new torch on membrane systems recognize this requirement and spec additional layers of membrane along the gutter edges. It only makes sense. My sense is that this home owner will have that soon enough.
Finding a leak on a tar and gravel roof is usually not too difficult for an experienced roofer like myself. Most times it’s easily found but once in a while it can be tricky for even a seasoned veteran. Persistence is the key. However, difficult was not the case today in Ladner. After sweeping the roof area near the drip location and using our secret tool to find the splits ( I can’t publicly tell you the secret or others roofers might start to use it and gain a bit on our success rate and thus gain on our market advantage too) we found more than we bargained for. The splits kept coming and coming the more we expanded our search area. How was this roof not leaking more than what showed up inside? The answer had to be in the vaulted ceiling and it’s ability to shed the leak water away from the inquisitive home owner’s vision. The photo attached shows the proper way to prep a roof before application of the patch. Yes. Those were some major splits.
There are two main categories of roofing. Low slope and steep slope. Low slope is anything that has a pitch of 4/12 or less and Steep slope is everything above that. Slope or pitch is usually noted in a fraction of twelve. Twelve is used as it relates to the old school measurement of 12 inches. Slope is based on rise compared to run. Rise is how vertical the roof climbs and run is the horizontal distance on an equal plane to the flat ground. So a slope of 4/12 means the roof rises 4” on a horizontal distance of 12 inches (or one foot). So if I may jump ahead and offer this example, a pitch of 12/12 would be a 45 degree angle. This is not a pitch someone can walk on without any form of help or fall protection gear.
The general rule of thumb for usage of roof systems is that everything above 4/12 gets shingled with asphalt, cedar, concrete, clay, metal or composite shingles. Anything below 4/12 should get roofed using a membrane system such as SBS torch on, EPDM rubber, TPO, PVC and the quickly disappearing tar and gravel roof systems. Shingles depend on positive watershed and are not entirely self-sealing. They rely on overlap and gravity. A membrane roof is equivalent to enveloping and is a continuous membrane system with no weaknesses. I have waterproofed planters in torch on membrane and they are continuously holding water.
Now shingle manufacturer’s want us to buy more of their product so they say we can put shingles on roofs that have as low a slope as 2 or 2.5/12. They have their low slope requirements and necessitate changes to the roof system other than what would be done on a 4/12 or greater roof. I have seen it done and it has worked. I exclusively use a GAF-Elk shingle because they are so well self-sealing and become almost membrane like once they have had the heat of the sun to activate the patented Dura-grip adhesive on the back of each shingle.
The steeper the slope/pitch of the roof the less water is going to adhere to the surface and erode the waterproofing material. Therefore it goes to say that a flat roof requires a qualitative waterproofing system as it may hold a large quantity of ponding water for extended durations, depending on the effectiveness of the drain placements. Flat roofs commonly settle over time also (or sag in the middle of the roof area where the structural support is at the least) and when the rigid drain, supported by cast iron plumbing pipes, doesn’t move it results in excessive standing water as the drain is now “high”.
The attached photo shows an interlock shingle application on a low slope roof in which the contractor should have chosen a membrane roofing system. Trust Crucial Roof Services to choose and install your low slope roof system. Roof system selection and integrity thereof is of primary regard in all our roofs installed resulting in absolute customer satisfaction and continued referral business.