Why do Commercial Roofing Bids Vary So Much?

When the time comes for you to look at replacing or repairing your commercial roof, you may find many that the bids you receive vary quite a lot. With this being the case, the question becomes, how do you select the best commercial roofing company when there are many to choose from? We suggest speaking to people around you and gathering information on the best commercial roofing contractors for the work you need to complete. Varying bids is one thing, but finding a highly skilled roofing contractor to support their bid is another.

Various factors will impact a bid and your decision when considering which roofing contractor to choose. We have put together a list of factors that can affect a roofing company’s overall offer:

The bids are not “apples to apples” when being compared:

An example of this would be if one of the roofing contractors proposes installing a TPO (thermoplastic polyolefin) membrane and the other proposes installing a PVC (polyvinyl chloride) membrane. The cost difference between the materials can vary greatly, and so will the labour. Although both products may provide a similar warranty for waterproofing, the PVC membrane is a self-extinguishing product resistant to oils and foliage. Roofing contractors commonly use this product on high-occupancy buildings such as hospitals, churches or schools that cannot be evacuated quickly.

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    Even when bids are “apples to apples,” one might be a little bit sweeter:

    If both roofing contractors are installing PVC membrane, but one is only offering a 15-year NDL (No Dollar Limit), and the other is offering a 20-year NDL, this would impact the overall price and the grade of material as well.

    Contractors must go through several more steps and requirements to qualify for a 20-year NDL than a 15-year NDL. Even though the same membrane gets used, a 20-year NDL requires a 60-millimetre PVC membrane, whereas the 15-year NDL only needs a 45-millimetre PVC membrane to meet the thickness requirement. This difference in thickness also translates into a cost variance between the two options.

    Roofing Company’s Overhead:

    Some larger roofing companies have a higher overhead than smaller companies, but that doesn’t always result in the larger company being more expensive. Larger companies may have more advantages, such as more collateral, allowing them to own larger equipment that gets the job done faster and, therefore, cheaper. These larger companies may also offer better discounts with their material suppliers based on the volume of materials purchased.

    Smaller roofing companies will have much lower or almost no overhead when the owner operates from a home office or maybe a small office. Even though they have lower overhead, they tend to have higher costs for materials and equipment, impacting their bids.


    Another difference is that some companies pay their commercial crews by the hour while others t subcontract their labour. This difference can impact the cost of labour, and with this being such a competitive market in itself, the demand for crews can be high, which will also impact prices. Typically, it is driven up in the summer with abundant work and down in the winter as work gets scarce.

    Profit Margin:

    Depending on the volume and quality of workmanship, a company may set goals for a profit of 10% to 35% profit. This variance in profit margin will again impact the amount bid on a job.


    As you can see, several factors go into a company’s bidding process. It is essential to understand everything included in the bid and, most importantly, that you are choosing a professional and reliable roofing contractor.

    If you are looking to repair or replace your commercial flat roof, give the MD Roofing & Sheet Metal experts a call today at (780) 439-7663.

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