Roofing Concepts and Issues

Decking. Decking, which is the sheathing under the roof, is commonly made of plywood. Water leaking through a roof may cause the decking to rot. Because nails hammered into rotted decking will not hold, rotted decking must be replaced before a new roof can be installed. However, it is difficult to know how much decking, if any, must be replaced before the old roof is torn off. Therefore, a common industry practice is to give a firm estimate on the tear-off/replacement roof and a firm estimate per unit of decking that must be replaced. To prevent unnecessary replacement, homeowners should ask the company to set aside damaged decking for their inspection.

Ventilation. Attic ventilation is extremely important. In the summer, attic temperatures rise dramatically. Moving air minimizes the temperature rise, lowering air conditioning requirements and associated electric bills. Excessive heat in attics can also cause shingles to get overly hot, which severely lowers their lifespan. In the winter, moving air helps prevent mold and mildew growth by removing attic humidity. If the roof is not properly ventilated or properly installed, most shingle warranties are voided.

The best ventilation systems are those that move the most air for the least cost. The ridge-and-soffit vent system is one of the best systems available. As does a chimney, this system employs the natural rise of hot air to generate airflow. Cooler air enters the attic through the soffit vents in the eaves. This air is heated in the attic, rises, and exits through the ridge vents at the highest point in the attic.

Leaks. Leaks can be caused by a number of factors. Ice dams can form during cold winters. These icy barriers keep water from being able to run off, leading to leaks. Most roofing leaks are caused by problems with flashing (metal placed in trouble spots, such as sharp angles in the roof). To prevent this problem, homeowners should hire high-qualified professionals to install or repair their roof. Roofers need to know the specifications of the roof and the flashing detail. Some roofers will use caulk to fix a leak, but this type of repair is rarely the correct way to fix a leak. It is usually a temporary solution, and the leak can return and cause even bigger roofing issues. Homeowners should ask roofers to explain how they are going to fix the leak. Most of the time, the flashing will need to be repaired in order to prevent future leaking.

Waves in the roof. If a roof has a dip or a hump, it may be caused by cracked or rotted decking. When looking at the roof from the ground, a slight wave or waves may be apparent. If decking is rotted, nails can easily back out, causing boards to rise up and create a hump. In cases such as these, re-roofing over existing roofing is not a good option. Rather, it is imperative to replace the damaged or rotted decking before putting a new roof on the home.

Cleanup issues. Many residents have reported hiring roofers who left a great deal of debris, such as nails, in the yard after completing the job. Typically, roofing companies put a dump truck or a dumpster in the driveway, which they use to dispose of debris. When the work is complete, the roofing company should walk a large magnet on wheels around the yard to pick up any stray nails. Debris from roofing jobs can easily fall into gutters, so homeowners should ask roofers to check their gutters and downspouts for any hidden debris. A good roofing company will do a final inspection in order to catch anything that was missed by the installation crew.

Gambling with rain. Some jobs involve tearing off the old roof before installing the new roof. If a heavy rain occurs while the house has no roof, severe damage can result. While some roofers take chances by tearing off the entire roof at once, professional roofers either tear off and replace a section at a time or use large tarps to cover the work area. Professional roofers do not take chances with rain.