In this tutorial I’m going to show you how to fix a small foam split next to a plywood seam. As a rule of thumb foam that is sprayed directly over plywood will not leak. This is because water cannot travel underneath the foam because it’s fully adhered to the wood. However there are some exceptions to this rule
1. A leaking penetration i.e. pipe , t-top, scupper ect.
2. A split at a plywood seam.
This split is only about 1 1/2 inches long but the damage it did inside was incredible.
foam split next to plywood seam
As you can see this is a very small split that can go unnoticed. Typically something like this would never leak. But what gives it away is the plywood seam right next to it.
1. First cut one side of the split in a V pattern
Split through to seam
2. Next use a polyurethane caulking to fill the crack. (It’s important you V it out don’t just caulk the top it will split again)
Caulk the hole
3. Tool the caulk with you finger or cardboard. Make sure you go past all the edges of the cut.
Tool the caulking
4. Now the repair is finished you can coat the caulking with elastomeric coating.
The foam isn’t the problem on this roof. It’s because of improper maintenance. Wrong materials used for repairs, neglect and abuse that has led to a total tear off of this foam roof and and new roof system being installed.
As you can see from the repair done on the picture above. Yes thats a plywood patch.
mastic on foam
In picture above you can see incompatible materials have been used that’s asphalt mastic with elastomeric coating over the top. It’s because of things like this that this roof is being torn off. Poor maintenance and poor repair practices lead to costly and early roof failures. You can see where the roof coating has cracked this is often times because of cheap coatings being applied to much and to often.
This is a short video showing the elastomeric re-coat process. As you can see they are back rolling as they go, this ensures the coating fills any little cracks or holes. Also this is done when there has been an aggregate added before.
The re-coat process involves more than just putting coating down.
1. Clean roof with a broom, leaf blower, and if necessary a water hose.
I have said it before and I’ll say it again. If your not careful in selecting the right roofing contractor you may end up with a roof that looks like the picture below.
This is what happens when a foam applicator drags the foam hose over wet foam. This kind of thing does happen from time to time but the real problem here is the fact that it was left like this. Normally you would take your grinder and grind it flat and then apply your coating, apparently this roofing contractor was to lazy to do it right. Kind of makes you wonder what else they didn’t do. Well take a look at the pictures below.
This picture shows all around bad foam detail. First off they foamed in the A/C condensate line and the A/C electrical conduit. So if for some reason you needed to replace the electrical or condensate line in addition to hiring an A/C contractor you will also need to hire a roofer. The foam detail is all around bad.
This is really a all to common mistake. 9 out of 10 foam roof leaks are due to a failed penetration or some other component and not the foam it’s self. If they would have put the foam they sprayed up the sides of the pipe around the base of the pipe this wouldn’t have happened. As you can see someone tried to fix this by brushing some elastomeric coating around the pipe and as you can see it didn’t work. The proper way to fix this would be to re-foam the pipe. If you didn’t have the money to hire a roofer to do it you could apply a thik bead of urethane caulking around it. It will be a semi permanent fix. By the way this type of failure is due to settlement and the lack of foam around the pipe.
In a nutshell this property owner paid some one to give them a new roof and then paid someone else to fix their mistakes. And believe me it’s not cheap, had they hired a roof consultant from the very beginning the job would have been done right the first time and would have cost them a lot less than it’s costing them now. Remember that cracked pipe how much damage did it cause inside the structure? How many pipes were failed like that…. About 9. So remember when you decide to have roofing work done it might be a good idea to at least call a roofing consultant to see what his fees are you might just be surprised. Or you can roll the dice.
What is a Cementitious roof ? Or also known as C-cure. C-cure is a light weight Cementitious concrete that is spray applied over a polyurethane foam roof. It is one of the most expensive foam roofs you can buy. The c-cure has a very high fire rating and is usually applied on schools, government buildings, high traffic roofs or anywhere you need a fire rating.
I was on one recently and took some pictures. The foam application part of the roof is just about as good as they come, but Cementitious part of the roof is as bad as they get.
The application of a Cementitious roof is as follows:
1. Polyurethane foam is applied at a thickness of the roof spec. usually @ 1 1/2 inches or greater.
2. An elastomeric roof coating is applied @ about 1 gal. per 100sqft.
3. A second coat of elastomeric roof coating is applied @ 1.5 gal. per 100sqft. At this time a #6 Aggregate is applied into the wet coating @ the rate of about 35-40lbs per 100sqft.
4. All verticles ”anything above the roof surface” walls, pipes, a/c curbs t-tops ect. are coated with an elastomeric coating.
5. Finally the C-cure is applied over the roof surface. It’s applied in both directions to prevent voids. The dry thickness is 1/4 of an inch. The finished surface should have a smooth apperance with only the top of the aggregate visable.
Below are some pictures of an inproper c-cure application that will lead to premuture roof failure. Also pictured are incorrect repair methods.
Failed c-cure roof due to improper application
Popcorn Looking c-cure roof
This next picture shows a repair done using an elastomeric roof coating. Elastomeric coating will not stick to c-cure so thats why this repair has failed.
Elastomeric coated c-cure repair
This next picture shows a c-cure repair done using an aluminum roof coating. You can’t use this coating on a c-cure roof.
You can't use aluminum roof coating on a c-cure roof
What happens now?
This deficiency was discoverd during a roof inspection. Good for the owner because the roof has not yet completely failed. The bad news is a $15000 c-cure recoat 10 years early. The bottom line here is had the building owner used a roofing consultant to over see this roof installation he wouldn’t have the problem he now has. This is more common than you might think.
In this tutorial I’m going to show you how to repair blisters on your foam roof. Foam roof blisters are not uncommon and are relatively easy to fix. There are many things that can cause blisters please refer to our F.A.Q for common causes.
Normally blisters are not that big of an issue to be concerned with. Unless you have alot of them , They are unusually big or they are broken. If the blisters are broken then prompt attention is needed to fix them because they can be a source for leaks. It should also be noted that blisters bigger than a baseball should be fixed by a roofing contractor who does foam roofing.
Blisters are fixed as a part of a routine roof re-coat.
In this first picture it identifys a golf ball size blister.
Cut the blister out using a razor knife (bread knifes work the best).
This is a golfball sized blister
Fill the hole with a polyurethane caulking. DO NOT use any other kind of caulking your repair will fail.
Use polyurethane caulking to fill the repair area.
Tool the caulking with a piece of cardboard or putty knife. Make sure you tool the caulking past all of the edges.
Tool the caulking
Coat the repaired area with an elastomeric roof coating. This is a permanent repair.
This is the same process a roofing contractor will use to fix blisters that are baseball sized or smaller and less than a 1/2 inch deep.
Below is a picture of a blister that you should not attempt to fix. If you have one that is broke and might be leaking you can caulk it then have it repaired later.
One thing that often damages a urethane foam roof is bird and bee damage. This type of damage is usually found near the edges of roofs or on top of parapit walls mostly on roofs with overgrown trees hanging over the top. What happens is birds peck holes in the foam and then the bees come and tunnel through the holes. This kind of damage is very easy to fix if caught early, but if left ignored it can cause extensive costly damage. I have seen complete walls and edges in need of complete tear off and re-foamed because this type of damage was ignored. The reason birds and bees do this is because one of the main ingredients in foam is sugar. Some ways you can help prevent this is by
1. Keeping trees cut back from the roof.
2. Place rubber snakes or plastic owls in the areas that are being effected.
In this tutorial I’m going to show you step by step how to fix this type of damage.
Things you will need:
1. Polyurethane caulking, DO NOT use any other kind of caulking they will not work (especially silicone) it will popout of the hole like a plug due to expanding and contracting.
2. A piece of cardboard or something similar to tool the caulking with.
3. elastomeric roof coating, disposable paintbrush and gloves
4. caulking gun.
Clean off the oxidized foam with a fingernail or brush.
Fill up hole with caulking.
Tool the caulking with cardboard or putty knife, apply a little pressure to make sure the caulking is down in the hole.
Apply a generous coat of elastomeric roof coating over the urethane caulking. This is very importantwith out this coating the suns uv rays will destroy the caulking and your repair will fail.
Your repair is finished. if you followed this tutorial step by step This repair is a permanent repair and no further action is required. This do-it-yourself repair can save you hundreds of dollars.
Here is an example of a roof installation that was doomed to fail the second it was finished. This is about a 10 year old foam roof that was installed over the top of 3 other roofs. When this roof was tore off we found a cockroach infestation. Standing water between layers. And a host of other problems. Had the homeowner obtained a roof inspection prior to the foam roof installation this would have forced the roofing company to tear of all pre-existing roof layers prior to the foam roof installation. In most cases you are only allowed to have one previous layer. This is determined by various factors to include, but not limited to the following:
1. That the roof structure is sufficient to sustain the weight
of the additional dead load of the roof covering.
2. Fire retardant requirements are maintained.
3. The existing roof covering is securely attached to the
4. The roof is structurally sound.
5. The existing insulation (if installed) is not water soaked
6. Roof drains and drainage are sufficient to prevent
extensive accumulation of water.
A failed 10 year old foam roof
In this picture it shows the roof layers being tore off and the discovery of water. There had been no recordable rain in at least 90 days.
Water in between existing roof layers
After a complete tear off, the roof is finished with a new ployurethane roof system. The new roof is properly installed and the homeowner should expect at least 20 years with proper maintenance.