What Is Silicone Roof Coating And Should I Use It For A Commercial Roof System?
Because there are a lot of question about the use of silicone as a roof membrane, today we'll be looking at roof restoration applications and explore the logistics and cost factors involved in a silicon restoration membrane.
What is the average cost of a silicone restoration membrane?
A silicon restoration membrane is a fluid applied, silicon membrane that is installed over an existing roof substrate. For a typical SRM installation on a 20,000 square-foot facility, we're going to be right in the neighborhood of $2 to the top end and possibly $3.50 per square foot.
While this is only and estimate and there are many variables that can go into the cost for any particular roof, this gives you a general idea of the cost compared to other commercial roofing solutions. That cost estimate covers both labor and materials.
Assessing the Roof - Infrared Survey
One method of assessing a roof is the use of infrared surveys to verify that we know where all the saturated anomalies of insulation are, and that we can remove those before we do the SRM installation. We do not want to trap moisture in any roof assembly. It's critical that we start with a dry, sound and clean substrate. Infrared is the most cost effective and most effective measure and way to determine where those saturated areas are.
Repairs to the existing roofs that are candidates for the SRM application, those roofs been out there for 15, 20, 25, 30 years or more. These repairs are the front line defense to your building. They're experiencing the harshest elements of your building envelope on a daily basis. Roof systems have finite life cycles. They start to wear out, things start to break down. So we want to make minor repairs to the areas that have degraded the most, if they're not too far gone that they can't be restored, but they still need some work to be bolstered back up. Some areas might have some tenting going on in the membranes that we want to address. Penetrations might just need to be reinforced a little bit before we do the SRM installation.
So after we've done the inspection and we've done some mechanical repairs, we need to clean the roof system. We're trying to adhere a fluid applied product to a 15, 20, 25 year-old membrane that's been laying there collecting dirt. So we have to power wash it.
There's two primary methods of power washing. You got a power washer source of water and a power washing wand. We do it on an industrial scale where we're doing a little bit higher pressures than the typical homeowner is going to be doing that at, and we do it at a large scale. We'll have four or five out there at one time. We use a reclamation power washing system. It's spinning with a high pressure washer, but there's also a vacuuming mechanism at that point that's bringing it into, and pumping it to a truck. The truck filters out the contaminants that are pulled up off the roof and is discharging clean water. That has a little bit of a higher cost, with all the equipment involved in that, but you're also sucking the water off at the same time, so your roof is dry much sooner and you can go to work potentially the same day as you're washing that roof, verses it might take a day or two when using the traditional power washing methods to get the roof back to a dry surface.
With the SRM, there are seam repairs that need to be performed. Reinforcing the membrane helps to prevent further leaks.
There are two primary methods to do that. You can embed a polyester mesh into a wetout coat that's reinforcing that seam and covered with another coat once cured. It is the lower cost of the two methods.
The second method is utilizing an adhesive backed, polyester reinforced tape or membrane to reinforce that. The tape is installed over the seams and covered with an layer of coating. So you still have to be clean and dry. That process costs more then utilizing just the polyester mesh.
Finally, the last step in an SRM. Now it's time to finally put down the magic juice. We're getting the silicon coating on the roof system. Most applications are getting a 10 year warranty, some will get a 15 year warranty and even fewer will get a 20 year restoration membrane application. Manufacturers are very comfortable with the 10 and 15 years and now we're kind of getting on that outside edge of is it really going to last 20 years, so the actual silicone and how it is applied affects the warranty as well. Some manufacturers are allowing a 10 year application to be installed in one coat. Some are even allowing a 15 year application to be installed in one coat.
Typically there's not much labor, it takes a little bit more time to put a little bit more coating down, but it really doesn't impact the overall cost of the project to go from 10 to 15, other than the additional material in one coat. Some roof conditions dictate that best practices says 2 coats need to be installed. You need to give this first coat down at a certain millage and then a second coat down at an additional millage, and the duration is affected by the thicknesses of both those coating applications. So again, you're adding more material to get from 10 to 15 years and potentially 20, but now you've got a second step of labor, which is a big cost driver. So a little bit of more material isn't terrible, but when you get into the second coat you do really drive an impact to the cost of the overall project.