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How to Compare Commercial Roofing Quotes

Wednesday, June 29 2022

On top of dealing with the demanding maintenance schedule of your commercial building and issues with tenants, you also have to monitor the condition of the building’s roof. It may be hard to know where to start when the commercial building that you own or manage required roofing work. Whether you need a brand-new roof or basic repairs, it is wise to learn more about the materials, costs and norms of the commercial roofing industry so that you can make a more informed decision for your property. In the end, getting the best roof and the most value from a commercial roofer comes down to comparing quotes. However, you may need some knowledge and guidance to make this decision wisely. The information we’ll provide below can help you prepare to compare commercial roofing quotes to get the most suitable roofer for your property.

  1. Why Get Estimates and How Many?
  2. Comparing the Roofing System and Materials on Your Quote
  3. Guide to Necessary Materials for Each Flat Roof Type
  4. How to Compare Labour Costs on Your Estimate
  5. How to Compare Roof Warranties on Your Quote
  6. Check for Insurance and License
  7. Ask About Start Date 
  8. Consider Customer Service
  9. Negotiating a Commercial Roofing Quote
  10. Are You Looking for a Commercial Roofer?


Why Get Estimates and How Many Should You Get?

Typically, building owners and managers opt to get three roofing proposals. Some companies have a policy to get three quotes as a bare minimum for any contracting work they procure. Even if you do not have this policy, fewer quotes will likely not give you enough information to make your decision. If you only get two quotes, and one is wildly lower, you can’t be sure which is the outlier. Is one roofer overcharging, or is the other undercharging? With three quotes, you typically get a fairer picture of the market, as the two other quotes will indicate extreme outliers. However, if you feel like you didn’t get a full picture, you can always solicit a fourth quote.

As you ask for the quotes, be sure that the roofing companies know that they are competing with other companies during the bidding process, as they may bring more competitive offers when they know you will be considering other roofers.

Comparing the Roofing Systems and Materials on Your Flat Roof Quotes

The first way to compare commercial roofing bids is to look at the systems and components that your prospective roofing companies want to install. If you get a quote for repairs, the materials are likely to be remarkably similar, as materials should match what you already have installed. However, some roofers may go further than others. If you see any material differences between repair quotes, you can ask the roofers why they have or haven’t included something that another roofer has. These answers are often telling.

IKO commercial membrane skids loaded onto flat roof

Quotes for brand-new roofs will typically have more variance in materials. Roofers may have different suggestions about which kind of roof is right for you. You have a choice between built-up roofing (BUR), liquid-applied systems and membrane systems, such as modified bitumen or TPO.

Of course, each roofer should be quoting for the same kind of roof. It’s no use to compare bids for BUR and single-ply roofs, as the material costs, labour, features and benefits of each are different. If you’re not comparing apples to apples, you’re less likely to get the full value from the bidding process.

You will still see discrepancies in the estimates if your roofers are all installing the same type of roof, even from the same manufacturer. For example, IKO has multiple different roofing vapour barriers for commercial roofs that your roofer may use in a handful of systems. That’s one reason it is important to have an itemized quote. When you see a difference in specific materials, you can ask about why your roofer wants to choose one vapour barrier product over the other. You may be able to get a lower price with a less expensive material or a higher-quality material for a better roof.

You should also ensure that each quote includes every material that is required to install your specific roofing system. If a roofing quote is low, it may indicate that your roofer has excluded an important material and wasn’t intending to install it on your roof. If this was left out of the quote by accident, they might try to charge you more for it later when they realize their mistake.

Necessary Materials for Each Flat Roof System

Use the following guides to get a general sense of what materials should be included in a quote for each commercial flat roofing system.

Built-Up Roofing (BUR) Systems

  • Decking or sheet metal.
  • Vapour retarder.
  • Fasteners and plates (may be optional).
  • Flat roof insulation.
  • Tapered insulation, if necessary.
  • Protection/separation/cover board.
  • Roofing felt.
  • Asphalt, such as Easy-Melt.
  • Base sheet flashing.
  • Cap sheet flashing.
  • Aggregate surfacing.
  • Drains.

When installing a BUR system, the number of layers and types of felt (organic vs. non-organic) is especially important. Take note of any differences between your quotes on this matter.

Modified Bitumen Roofing Systems

1. Heat-welded or fully adhered option:

  • Drains.
  • Decking or sheet metal.
  • Vapour retarder.
  • Insulation
  • Asphalt or adhesive.
  • Fasteners and plates (may be optional).
  • Protection/separation/cover board.
  • Base sheet.
  • Cap sheet.
  • Base sheet flashing.
  • Cap sheet flashing.

2. Mechanically attached roofing systems:

  • Drains.
  • Decking or sheet metal.
  • Modified vapour protector.
  • Insulation.
  • Fasteners
  • Protection/separation/cover board
  • Mechanically attached base sheet, such as Fast-N-Stick 180.
  • Base sheet flashing.
  • Cap sheet.
  • Cap sheet flashing.

Modified bitumen roofs are very flexible, and your roofer may install them as a two-ply or a three-ply system. There is also a major difference between the modifiers used in the modified bitumen: APP or SBS. Each specific cap and base sheet will have its own advantages and disadvantages, which are worth exploring to find the best roof for you.

Single-Ply Roofs (EPDM, PVC or TPO)

1. Ethylene propylene diene terpolymer (EPDM):

  • Drains.
  • Decking or sheet metal.
  • Cover/protection board.
  • Vapour retarder.
  • Fasteners (may be optional).
  • Insulation.
  • Adhesive (optional based on system).
  • EPDM membrane.
  • Top reflective layer (optional).

2. Polyvinyl chloride (PVC):

  • Drains.
  • Decking or sheet metal.
  • Cover/protection board.
  • Vapour retarder.
  • Fasteners (may be optional).
  • Insulation.
  • Adhesive (optional).
  • PVC membrane.

3. Thermoplastic polyolefin (TPO):

  • Drains.
  • Decking or sheet metal.
  • Vapour retarder.
  • Cover/protection board.
  • Fasteners (may be optional).
  • Insulation.
  • Adhesive (optional).
  • TPO membrane.


Vegetative Roof Systems

Vegetative roof systems typically use a cold roof and may also use two-ply SBS membranes.

  • Drains.
  • Decking or sheet metal.
  • Cover/protection board.
  • Vapour control barrier.
  • EPS insulation.
  • Waterproof membrane.
  • Root barrier.
  • Drainage layer.
  • Filter.
  • Substrate (soil replacement).
  • Plants (in plugs, mats or trays).

While it’s important to make sure that your commercial roofing bid includes all the layers listed above, the specific type of material is essential too. Different roofing systems may have more specialized parts to achieve different features. There are unique fire-resistant sheets, heavy duty membranes, cold-applied membranes, flame-free membranes and many more, especially if you choose a modified bitumen roof. Ultimately, you will need to talk to your prospective roofers to get a sense of whether or not these specific materials and systems are best for you.

How To Compare Labour Costs on Your Estimate

Your roofing quote should also cover the cost of labour. Some roofing companies do not separate their costs for materials and labour, making it harder to compare quotes fairly unless both quotes offer the exact same materials and roofing products. You can get around this by including specific material requirements in your request for proposal (RFP). With all of your potential contractors on the same page, you should be able to make a more direct comparison on labour.

The chances are that the three estimates you receive will vary in labour costs too. There are many factors that may explain this difference, including timeline, subcontractors, experience, technology, safety and incidentals.

1. Timeline

It is important that your roofing company completes the job in a timely manner to limit disruptions to and complaints from tenants. Comparing labour costs to the timeline a company expects to complete your roof work may help you see if the quotes are reasonable. What if one company believes the roof will only take them a week, while others believe it will take two or three? The company with the lower quote and shorter timeline may be underestimating the job, underestimating the complexity of your roof or have more staff that allows them to actually complete the job faster. The opposite may be true — that the company quoting a longer timeline is overestimating the job.

2. Subcontractors

Subcontractors may also explain extremely low labour quotes. These are independent roofers that the company you contract with pays to complete part or all of the job. It’s natural to be concerned that a subcontractor may offer lower-quality work and introduce risk and liability to your property. However, that liability is generally the main contractor’s, and they often use subcontractors that help them save time or have special skills they benefit from.

If you allow subcontractors to work on your property, make sure that these companies are only contracted to the general contractor and are not entering into a legal agreement with you and that they have the mandatory insurance required in your jurisdiction. Please consult your local counsel prior to allowing subcontracting, and review the roofing contract before signing.

3. Experience

The roofing company’s level of experience may also explain differences in labour costs. Companies that are more established may charge more, but that doesn’t mean they necessarily do a better job than those with more moderate quotes. Those who are newer to roofing may charge less to build their business and get more experience. Roofers know that they need to establish a good relationship with building superintendents, property managers and other stakeholders to get continued work. Roofers know that for you, a building stakeholder, the trust factor is highly important. If you’ve had a positive experience working with their roofing company in the past, you will likely reach out to them for a quote on any future roofing work you have.

Look for the most value, those businesses that you feel will do a good enough job for your purposes but that still charge reasonably for the value of that work. In time, you will likely come to rely on the roofer that you choose, calling them first when there is a leak and asking for their quote when you require a reroof. Forging a relationship with this roofer will be in your best interests.

4. Technology

Companies that have invested in new technologies may save time and therefore quote less for labour, even if they offer superior service. Technological advancement does not have to be as groundbreaking as a thermal imaging camera; instead, the company that simply has the better tools may work more accurately and faster. Teams with robotic welders, induction welders and roof cranes may save on labour time and may be more precise, ultimately ensuring your building receives a higher-quality roof.

Thermographic Cameras are Important for Roofing Professionals

5. Safety

Rarely does a roofing quote include information about the safety procedures that your roofers will take on the job; however, safety is still worth discussing with them. Those quotes that are markedly lower than others may reflect the company’s lack of investment into safety equipment or a willingness to forgo safety practices to accomplish their work faster. Both are major red flags. Discuss with your roofers the kinds of safety practices they follow to protect their own staff and those they follow to protect the tenants, customers or staff in your building.

6. Incidentals

Lastly, you might consider if all companies offer the same “incidentals,” or labour that some roofing companies consider extras. They may, or may not, clean up after their work or offer disposal for old roofing materials. Ask if your roofer has included these tasks in the quote.

How To Compare Roof Warranties on Your Commercial Roofing Quote

It is always critical to get the details of your limited warranty in writing so that you can hold your roofer to their promises if your roof does develop a problem. There are also manufacturer limited warranties — those offered by the manufacturer for material defects — and other limited warranties from the roofers themselves. Typically, you will only get coverage under a manufacturer’s limited warranty if the roofer installed the roof according to the manufacturer’s standards. There may be other requirements for a manufacturer’s warranty. Frequently, roofers must complete a manufacturer training program in order to qualify for and offer a warranty from the manufacturer. Your roofer should be able to explain exactly which warranties they can offer.

You should also get details about the limited warranties, including their coverage and term length. The standard manufacturer’s limited warranty on a commercial roof is 10 years, and contractors typically offer one- or two-year warranties for their labour. However, you may find both types of warranties that are longer or shorter. Limited warranties may also cover different parts of the roof. The manufacturer warranty may only cover their own products, such as the roofing membranes, but, more commonly, premium manufacturer warranties cover labour after the first two years. The roofer’s warranty may cover the labour to fix any of the materials that they installed.  Also, your roofer may include limited warranties in the overall cost of the roof, or a roofer may charge you for their specific limited warranty.

Check for Insurance and License Status

If you have not already looked into your potential roofer’s license and insurance status, you should take this opportunity to confirm them. Some roofing companies include their license number on their quote, but if not, they should be willing to offer it to you, along with confirmation of their insurance. Roofing company insurance should include general liability of at least $2 million, worker’s compensation and a bond (in most areas of North America). Commercial roofers working with heat-generating equipment or open flames, including those working on BUR, should also have hot work insurance. This is a separate insurance policy that covers the risks associated with open flames, heat and sparks. You should be able to find the contractor’s specific coverage amount on their quote.

Ask About Start Date

Some building owners assume that a roofing company will be ready to start work as soon as they accept the quote. Unfortunately, that’s often not the case. If you are on a short deadline for a project or are trying to limit the impact of roof replacement on your business, it’s best to ask roofers when they can start before you accept the quote. If one roofer isn’t ready for a few months, but another can start in a few weeks, then that may be the deciding factor for you.

Consider Customer Service

How your roofer delivers the quote can matter as much as the quote itself. After reviewing the estimates, you should consider your customer experience so far. Has the roofer been clear and open to questions? Have they responded to you promptly and treated you with respect?

While quality roofing companies will strive to always give you a great customer experience, those who are less strong in this area put their best foot forward during the bidding process, only to drop off a bit later. If your experience with the company’s salespeople has been anything less than positive, you should strongly consider how you’ll be able to work with the roofer moving forward. You might also consider how subcontractors could affect your customer experience — as they may not have the same standards of service as the company which gave you the quote.

As a company, you might also consider how easy it will be for different people in your organization to keep up to date on the roofing project, if that is a concern for you. While a property manager may be handling the whole roofing process, that manager may still need to update other stakeholders about the progress of the project. This may be simpler if you work with a commercial roofer who offers online updates, customer portals and other customer relationship management solutions. If getting other people up to date on the project is as simple as having them log into an app, you may save significant time and hassle.

Negotiating a Commercial Roofing Quote

Sometimes bids are set in stone, and negotiation is simply not possible. Other times, negotiating can give you a deal that works better for both yourself and the roofer. While you have your yearly capital expenditure budget in mind, your roofer needs to consider their own pricing structure. Many commercial roofers do not make the kind of margin you expect even though a large roofing job could be quoted for $100,000. Typically, negotiation will go best if you can explain your concerns about the roofer’s quote. If you explain your reasoning, the contractor may find room to compromise that you may not have considered because they need the work.

For example, let’s say you communicate to a roofer that you are strongly considering a roofer that quoted lower than them, in part because they use cheaper material. The roofer may alert you to a good reason that this material isn’t right for your roof. Even if you do not choose the second roofer, at least you have learned something that you can discuss with the roofer who gave you the lower quote.

Roofers may be willing to switch materials, avoid using subcontractors for your job, start earlier and make all kinds of other concessions to match quotes from other roofers. This is why the bidding process is so important. It gives you more information and leverage than you would have had before and can empower you to make the right choice for your property, business and tenants.

You already have so much on your plate, from tenant complaints to regular building maintenance. By taking the time to compare roofing quotes carefully, you avoid adding more headaches to your plate.

Are You Looking for a Commercial Roofer?

What if you don’t have three quotes for your commercial roofing project yet? Get a quote from a commercial roofer through IKO’s Contractor Locator.

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