Purchasing a New Flat Commercial Roofing System

    Montgomery County Planning Commission/flickr 

    How many people actually know anything about purchasing a new flat roofing system? Did you know that 85 percent of all flat roofing systems are installed with a commercial product called modified bitumen? Modified bitumen is produced in thicknesses of 3.5 to 5.0mm sheets 3 inches wide by 33 inches long. The system is most commonly applied with a torch. The bottom of the sheet is liquefied and applied over insulation and or a felt-paper base-sheet.

    Contractors bidding on projects regularly include in their contract that they are installing a 15-year material. The job is sold, and then the contractor delivers a 10- or 12-year modified bitumen material to the client. The client never knows or thinks to check.

    1. Always ask for the materials receipt upon delivery of materials to your project. Always call the materials supplier and ask him what the warranty is on the materials delivered. Check to make sure the brand name matched the material quoted in the contract.

    2. Ask the contractor: “Are you a Manufacturer’s Certified Installer of the materials you are specifying?” This single question will revolutionize the industry. You will be stunned to find that no one bidding on the job is certified to install the materials.

    Now you ask yourself why. The manufacturer would love to know that every roofer installing its product is certified to do so. This in essence means that the roofing contractor has had his work inspected regularly and that the manufacturer of the materials validates that this contractor knows how to perform all of the detail work, as specified by the manufacturer.

    If the materials are not installed per the manufacturer’s specifications, then the materials have no warranty. In essence, if you do not hire a manufacturer’s certified installer, you have absolutely no protection and, almost always, a roof that was installed to a substandard quality level. Ask that the contractor supply you with the warranty documentation supplied by the manufacturer of the materials you have in your contract.

    At the beginning of the project, ask the contractor to inspect your new roof when it is finished and give you a written report or letter to substantiate that the roof has been completed to the manufacturer’s specifications.

    I recommend that you add this wording to your contract:

    The roofing system, including all flashings and details, at [my address] is completed to the manufacturer’s specifications.

    I, [contractor], will stand behind this warranty. In the event that [client] experiences leaking, I will respond within 24 hours and correct any and all deficiencies in my workmanship. In the event that [contractor] does not respond to [client’s] call for service, I have the right to contact another contractor and make repairs to our new roof to stop further leaking. [Contractor] will reimburse [client] for any and all out-of-pocket expenses to rectify defects in his workmanship.

    3. The manufacturer recommends that this new modified bitumen system be covered with a fibrated, silver asphalt base reflective coating. This is an asphalt base coating that has a silver pigment in it to block the sun’s UV rays from wearing out the material. This coating is to be applied at a rate of 75 s.f. per gallon. Ask the contractor at what rate he will apply the coating. Most contractors do not know the answer.

    Check to see that the contractor has delivered enough coating to apply to the system properly. In almost all cases, the coating is applied too thinly and consequently does not last.

    Take lots of photos before, during and after completion. Pictures are worth a thousand words. Download them to your computer and make three back-ups on CD. Put the back-up photos in three different locations. If you ever need them for insurance or legal purposes, and or when the building is sold they will be available.

    This article was written by Robert J. Skertich, President, The Patriot Construction Group, Inc. It was published in the Wall Street Journal, the SF Chronicle, and the Chicago Tribune.

    Please address all questions and comments to:

    Robert J. Skertich
    Patriot Construction Group, Inc.

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