What questions should you ask a roofing company before hiring them?

When hiring a roofing company, knowing the right questions to ask can help you avoid costly mistakes and ensure you're making a good investment. The cost of a roof replacement is a major expense, so it's important to know who you're hiring and what to expect.

From verifying credentials to understanding payment terms, the right questions can reveal a roofer's reliability, experience and professionalism. We spoke with Mark S. Graham, vice president of technical services at the National Roofing Contractors Association (NRCA) , about the key questions to ask a roofing company before signing a contract.

Check credentials, licensing and reputation

Graham said the first way to start is by researching potential roofing contractors. Talk to your friends, family and neighbors for recommendations (or roofers to avoid). 

"Word of mouth is always real big with me," Graham told Yahoo Local. "A happy, neighboring customer is always good." Looking for companies with a strong local track record provides reassurance about their reputation.

The NRCA recommends verifying that a contractor has a permanent business address, phone number, tax identification number and business license where required. Also, confirm that the roofer carries liability insurance and workers' compensation coverage that covers the entire duration of the scheduled roofing job.

While many roofers aren't technically "certified," some are "approved" by specific manufacturers. "If a contractor is approved, he's usually pretty proud of that and will be willing to tell you as part of their sales approach," Graham said. Our guide to roofing certifications (and why they matter) offers more details.

Licensing requirements vary by state and local jurisdiction. For example, roofing contractors in Illinois must display license numbers on proposals and ads. "If a license is not prominent, I suggest you move on to a different contractor," Graham said.

Check credentials through online reviews, local databases and references from past clients. "If a contractor's doing a good job, he's usually going to use that job in marketing and promotion," Graham said.

Additionally, check if the contractor is a member of a local, regional or national roofing industry association such as the NRCA. Membership often signifies professionalism and a commitment to the industry.

The NRCA also suggests checking with the Better Business Bureau (BBB) for complaints, accreditation status and ratings before hiring. (And read our guide on how the BBB's rating system for local businesses works.)

Graham advises being cautious of contractors who show up uninvited. "If someone drives by and says, 'It looks like you need a new roof,' that's somebody I suggest you have move on," he said.

Review the proposal and scope of work

A detailed written proposal is essential. Be wary of vague descriptions.

"If the proposal simply says 'take off old roof, put on a new roof,' you need a lot more information than that," Graham said. A thorough proposal should outline whether the roof will be torn off, how debris will be handled, what materials will be used, flashing details, warranty information and payment terms. "The more information that's on the proposal, the better."

The NRCA advises insisting on a written proposal that includes the project's start and end dates and payment stipulations. Also, ask about project supervision and quality control. Find out who will oversee the job and how many workers will be on-site. 

Some roofing companies provide background checks for roofers, while others use subcontractors. Ask the company if background checks are performed. If not, ask how long the crew has been with the company to look for signs of longevity and trustworthiness.

Additionally, Graham explains that "not all warranties are created equal. Some only cover materials, but others include workmanship — understanding what's covered is key."

Compare pricing and payment terms

Multiple estimates may not always be feasible depending on the time of year, especially during high-demand periods like the summertime. "If you get one or two and you have a good vibe about that contractor, I'd be comfortable with it," Graham said. A trustworthy contractor should explain the work in detail and help you make informed decisions.

Graham said to be wary of price discrepancies, as a significantly lower bid might indicate corners are being cut. "If somebody's doing more work, chances are they're going to be entitled to a higher price," Graham said.

The NRCA advises against going with the lowest bid before considering overall value. Remember that price is only one factor in choosing a contractor. 

Graham strongly recommends against prepaying for roofing work. "Prepaying a contractor or putting money up front is something NRCA suggests should be avoided," he said. "You should pay for work that is complete."

Payment should be made upon completion for short-term jobs. Our guide to roofing deposits and how to pay a roof offer more insights.

"Use the payment as the final signification of acceptance and approval — that way, you stay in control," he said.

Final tips for hiring a roofer

Roofing projects can seem overwhelming, but hiring the right contractor makes all the difference. "If you're dealing with a top-of-the-line roofing contractor , it's not a painful experience," Graham said. "It's just something that folks dread, like having to get your car repaired."

Communication is key, too. "If something comes up during the job, a reputable contractor will communicate that with the homeowner, explain the options and provide a fair price for additional work if needed," Graham said.

His final piece of advice? Think about your long-term plans before choosing a roofing system. "Are you going to be in the house for the long term? Is this a lifetime decision or are you going to be selling in a couple of years?" Graham said. "That all dictates how much you should be willing to spend on a roof."

If you plan to stay in your home for decades, consider high-quality materials and aesthetics that enhance curb appeal. "Treat a roof purchase as a major purchase, not just minor maintenance," he said.

You can hire a reputable contractor who delivers quality work and peace of mind by asking the right questions.

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