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6 Common (and Avoidable) Roofing Mistakes

1. Choosing a Contractor for the Wrong Reason  This important decision will have the most effect on the outcome of your roofing project. Are you choosing a contractor because you only sought out one estimate? Are you choosing a contractor because they provided the cheapest bid? These could be mistakes.

The best policy to follow when choosing a contractor is to always solicit at least three bids. This does involve a bit more inconvenience at the start, but it is the single most important piece of the project. Ask contractors if they provide free estimates, and, if so, invite them to bid. You can"t get too many bids.

The cheapest bid is not always the best choice. Pull out your magnifying glass and go over each bid in fine detail. What are the differences in material? What are the differences in scope of work? What are the differences in warranty? You may find out the cheapest bid is missing key items, such as removing the old roofing material prior to installation of the new roofing material. Ask a lot of questions and do your own research.


Additional information on choosing a contractor can be found on Pro Roofing"s website ( 

2. Roofing Over Old Roofing Material Some property owners will try to save on costs by roofing over the existing roofing material. In reality, the cost savings is a fraction of the total budget and will likely end up costing more in the long run. More than likely, re-roofing over old material will cover up existing problems, cost more to repair if a roof problem comes up, and will not last nearly as long as a roof that was built on a clean roof deck. Re-roofing is not a cost effective approach. Additional information of re-roofing can be found on Pro Roofing"s website ( 

3. Ignoring Roof Ventilation Every manufacturer of roofing material has detailed specifications for roof ventilation. Insufficient ventilation (heat build up) will cause premature aging of roofing material and will dramatically affect energy efficiency of the building. Manufacturers provide these specifications to protect their material warranties. The fact is that manufacturers will look for reasons to deny a warranty claim. Improper ventilation is commonly cited as a reason for having warranty claim denied. Proper ventilation also protects against condensation issues in the attic space and ice damming. 

4. Mixing Shingle Lots A little known detail in the shingle industry is that manufacturers produce shingles in lots. Asphalt shingles are manufactured in countless styles and colors. Shingle granules (usually mica or silica based) are applied to the face of asphalt shingles to give it color and protect the shingle from harmful UV radiation. The granules are colored and mixed at the factory before application to the shingle, and the mixture may vary from lot to lot. Therefore, the manufacturer clearly labels the shingle packaging with a lot number and manufacture date. Should the contractor mix shingle lots at the time of application, the roof may turn out to have a checkerboard-like appearance. Lot differences can be surprisingly dramatic. 

5. Skipping the Building Permit In most municipalities, a building permit is required for roofing. Ultimately, it is the property owner that is held responsible for building permit acquisition, and the fines/hassle incurred for not having a permit is just not worth it. Should you contractor be unable to acquire a permit, a red flag should immediately go up. 

6. Not Requiring a Lien Waiver from Your Contractor and Material Supplier Way too often, unsuspecting consumers find themselves entangled in legal issues after construction projects are complete. What happens if you pay your contractor in full, and the contractor fails to pay the supply house for materials? That supply house will place a construction/mechanics lien on your property that will likely hold up in a court of law. You could end up paying twice for the same material. Legal issues are easily avoided by following these two steps: 1. Provide as little money as down payment as possible. The really good contractors won"t even ask for a down payment. Lesser quality contractors, with no cash reserves, will need a down payment in order to purchase material and labor for the job at hand. 2. Before you place a check in the contractor"s hand, you must require a signed lien waiver from the contractor and the supply house. This ensures that the supplier has been paid and the contractor has no ability to file a lien in the future. 

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