Even though every roof is different, you want to make sure the main items are clearly stated in the proposal so you know what you are getting. Here is a list of common standards in a professional roofing proposal.
Tear off or shingle over?
You want to make sure the contractor clearly states if they are going over the existing shingles or completely removing all existing layers (There could be multiple!). Here in Lansing, the maximum amount of shingle layers on a roof is two.
You never know what surprises lurk under a roof's shingles, so you always want to have provisions in place for if you run into damaged decking. Make sure clear and precise actions are specified in the contract for however much decking is replaced.
Learn more here: Wood Repair & Decking Replacement
Crickets and saddles
When the roof is torn off, it's the perfect time to build any new crickets or saddles that are needed. Whether you have a chimney that is causing leaks or a dead valley that is not draining water, make sure you get them handled at that time.
There are all sorts of roofing underlayment out there and each one serves a different purpose. Make sure that the right type for you is stated clearly in the proposal.
A new shingle is useless unless it's flashed appropriately. When replacing a roof, it is important to have the old flashings replaced with new. Make sure the proposal states where old flashings are being replaced with new.
Shingle manufacturer and series:
Never allow a contractor to put "Dimensional shingle" or "Architectural style shingle" on your contract. With those types of vague statements, you could literally get something from the bargain bin at the local box store. Make sure that the shingle brand and series is clearly stated. For example: "CertainTeed - Landmark" shingles. CertainTeed is the manufacturer and Landmark is the series.
In order to ensure the longevity of your roofing investment, make sure that your contractor addresses any ventilation concerns you have in the proposal. There are many different types of ventilation systems for different type of applications. Always make sure to know which roof ventilation system is right for you.
Material and workmanship warranties
Typically the shingle warranty is covered by the manufacturer, but the workmanship is almost always covered by the installer. Make sure that the warranties are clearly stated in the proposal so you know who to contact if there are any issues once the project is completed.
Cost and payment structure
Once you are comfortable with all the other aspects of the proposal, it's time to go over the numbers. Replacing your roof is a costly process and you don't want to skimp when it comes to your home. You will want to have the cost clearly defined along with the provisions for any extras that may come up. Typically companies require a downpayment to get started, just make sure that the terms are written in a way that you fully understand them and make sure to keep a record of any payments made along the way.