Screw down metal works great in agricultural settings, on pole barns, warehouse roofs, and light commercial roofing applications with simple roofs designs. Here are the 8 best reasons we could think of as to why we don't recommend you have pole barn metal roofing installed on your home.
1. There are approximately 70 screws per each square of metal roofing. On average 2,000 sq ft home in Indiana that is somewhere in the neighborhood of 2,100 - 2,500 screws or potential leaks in the future.
2. Even though the screws have a rubber washer that is supposed to make a seal against the metal to keep water out, the screw must be driven in correctly and at the right depth. Under driving a screw won't make a seal, over driving a screw will damage the rubber washer, and a screw driven at an incorrect angle won't seal either.
3. The metal panel may last 50 years but the rubber washer keeping the water out will only last 9-15 years. Metal has the highest expansion and contraction factor of any other roofing product on the market. That means each day it expands with daytime heating and then contracts at night as the temperature cools off. This daily expansion-contraction cycle is too much for rubber washers and over time they deteriorate and loose their seal.
4. Screw down metal wasn't designed to be installed on homes. Using this metal on houses with skylights, chimneys, pitch breaks, and valleys will have you relying heavy on caulking and metal roof sealants to stay leak free.
5. Screw down metal is a metal roofing product, not a metal roofing system. It does not have the necessary interlocking parts and pieces required to water proof a home long term like other types of metal roofing such as standing seam metal.
6. The investment of a metal roof on your home is too large for it not to last.
7. Many homes don't have thick enough wood sheeting for screws to bite into a 3/8 plywood, even 1/2 plywood sheeting isn't enough wood to hold metal down long term. The pull out value of the wood is too low and screws will eventually work loose causing leaks.
8. Leaks around the screws are very hard to find. With over 70 screws per sq of metal roofing, finding and fixing leaks on this type of metal can be difficult to say the least.
Instead of pole barn metal roofing, try standing seam metal roofing. It is more expensive but it will last. If your budget won't let you put on a standing seam this time around think about a shingle roof. It may not be what you want but it will work better on your home than a screw down metal roof.