By Jim Donovan

PHILADELPHIA (CBS) — Home improvement season is in full swing. Many general contractors and companies hire subcontractors for large remodeling projects or specifically for electrical work or plumbing. But if you’re not careful, that home remodeling job can take a turn for the worst. In this week’s Angie’s List report, Jim Donovan explains why it’s key you do your homework when it comes to subcontractors.

Whether your adding an addition, remodeling your kitchen or renovating part of your home sometimes the contractor you hire will call on others for help.

“In a large project it’s not unusual for a contractor to hire subcontractors who specialize in certain trades whether it be a plumber, electrician, even a roofers. But it’s important for you as the consumer to know who they are hiring check them out as well,” said Angie’s List founder, Angie Hicks.

So ask for a list of subcontractors your contractor might use. Ask friends or family about them and check online reviews.

And if you’re doing a big job, talk to the general contractor about a lien waver.

That’s basically going to protect you against the contractor not paying the subcontractor because if the contractor doesn’t pay his subs, they could potentially put a lien against your property. If the contractor refuses to have a lien waver it’s a red flag and you should walk away,” said Hicks.

More from Angie:

Types of Contractors

· General Contractor (GC): Type of manager who is in charge of overseeing the entirety of a project. For a home remodeling job, the GC will meet with the homeowner to go over the initial project details, estimate the cost of the project, draft a contract, hire workers and handle the daily operation of the job. General contractor usually don’t perform any of the labor, but instead hire skilled tradesmen as subcontractors.

· Subcontractor: A worker who is hired by a general contractor to perform the obligations of another contractor’s contract. Also referred to as specialty contractors or “subs,” subcontractors are typically hired to perform a specialized type of labor. They are the plumbers, roofers, carpet installers and electricians who are essential to any large remodeling project. As the name implies, subcontractors work under contract with, and get paid by general contractors.

A nationwide Angie’s List poll found:

· When asked what aspects of the hiring process or contract were important – 10 percent of the respondent said lien wavers.

What is a lien waver?

If a home improvement contractor fails to pay his employees or fails to pay for the building materials used in the project, a lien can be placed on your property and you, the property owner, can be held liable for the unpaid expenses if a lien waiver was not established.

· To avoid unexpected fees or liens, homeowners should consider always including a lien waiver or lien waiver clause in the project’s contract. With a lien waiver, when the project is successfully completed, both parties sign off and state that the contract obligations have been met, including the general contractor making all necessary payments to materials suppliers, subcontractors or vendors.

· If the general contractor doesn’t agree to sign off on the lien waiver, you can withhold payment until he or she has proved they’ve paid their suppliers or subcontractors.

· One of the most essential things to know about liens and lien releases is how they’re enforced in your area. Although the general principle is the same for most areas, each state or municipality has different standards for the application of liens and their releases.

Angie’s List Tips: Know your subcontractors

· Ask your general contractor for a list of subcontractors to be used on a project, and then check the subs out.

· Angie’s List recommends soliciting at least three bids, properly vetting contractors and subcontractors by checking references and verifying licensure (if applicable), bonding and insurance, and negotiating a detailed contract.

· Ask the contractor how long he/she has worked with the subcontractors. What is their experience working together?

· Insist on a lien waiver, which protects the homeowner from liability if the general contractor fails to pay the subcontractors.

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