You probably already know that you should consider replacing your home's roof if it's between 20 and 25 years old or shows signs of disrepair from wear and tear or old age. But what you might think about replacing is your detached garage's roof. Even the roofs of garages can experience similar issues as residential roofs over the years, as well as new problems, such as sheathing problems and damaged garage doors. These issues can potentially place stress on the garage's walls, ceiling, and foundation. Here are two reasons you probably need a new roof for your detached garage.

Sheathing Damage from Holes

While you may be able to see expansive openings or holes in your roof by looking at it from the yard or street, you may not be able to locate tiny holes right away. The small holes you don't see may actually cause the most problems for your garage in the future, especially if they affect the stability of the roof's sheathing.

Sheathing describes the plywood or particle board used to cover, support, and strengthen roof decks. The material behaves as a glue that essentially holds everything together and provides a strong base for the roof's underlayment, waterproof layer, and shingles. If the sheathing of your garage becomes damaged, it may lose its supportive features. The roof might cave or collapse during a strong storm or blow off during heavy winds.

Replacing the roof of your detached garage provides you with an opportunity to repair the sheathing. If the sheathing is damaged in a few places, roofing contractors may replace the material in those locations only. If the sheathing has substantial problems, contractors may suggest that you replace the entire structure to protect your garage and its contents. In this case, you may want to use a sheathing material that works best for the type of weather you have in your area and the type of material you plan to place on your roof. 

For instance, if it rains a lot in your area, you may want to use a sheathing made with sealed or coated plywood. Coated or sealed plywood is more water resistant that materials like Oriental strand board, which tends to swell up when exposed to moisture. However, strand board may be a better choice for your garage if you live in a dry area and want a roof that can withstand heavy loads. If you're unsure about the type of sheathing to use, a roofer can help you decide.

Water-Damaged Garage Door

Your garage door may also be a reason to replace the roof. Garage doors usually experience moisture problems when water runs beneath their thresholds. But if the roof develops a leak, water can also affect the door if it penetrates the interior and rots the wood. Rotting wood can potentially attract insects, such as termites and beetles, over time. The pests not only weaken the door but also may cause it to fall. 

If you inspect the roof line above the garage's door, you might find signs of water and insect damage. The wood may appear crumbly in places, or it may smell musty and damp. In addition to physical problems, the garage may not open and close properly if it's damaged by rainwater and moisture. The door may make noises when you try to use it, or it may stick in place.

You can have a roofer check the moisture content in the roof line and garage door to see whether water damage is a problem. If so, you may want to replace the roof, sheathing, and seals around the garage door to protect your garage. You may also choose to install a water barrier above or along the roof line to help redirect water away from the door. As with choosing the right sheathing, a roofing contractor may discuss your best options for this step as well.

For more details about replacing your detached garage's roof, contact a contractor such as Affordable Roofing & Gutters today.