Metal Roofing

I just installed a new standing seam steel roof on my home and it is awesome! If a new roof is in your future, you would do well to consider metal. A metal roof can provide significant benefits for you and your home.

History

Metals have been used for roofing material for a long time. Copper shingles have been found on architectural ruins dating as far back as 300 years BC. Lead has possibly been used for an even longer period. Industrial age mass production methods included taking sheets of galvanized steel and roll forming them into stiff corrugated panels. These corrugated steel panels were used by the billions during WWII then salvaged afterward to roof barns and other shelters. Many are still in use today. Recycled examples with a nice layer of rust and patina are actually in high demand.

Durability

Metal roofing is extremely durable and is known to endure most types of severe weather, including snow, rain, hail (dents) and sun. It is tough enough to stand up to significant abuse without failure. The coated, standing seam material used on my house came with a 50-year warranty. I have in the past had many kinds of roofs, including wood shake, wood shingle, composite asphalt, and tile and none have come with warranties like that. I’m pretty sure I won’t be around to see that warranty run out, but I like having it nonetheless.

Materials

Metal roofing is available in steel, galvanized, zinc, copper, aluminum and alloys with trade names like Galvalume and Zincalume. The metal material can be roll-formed into sheets or stamped into designs that emulate shingles, tiles or shakes. Finishes can be applied to achieve just about any appearance and with the right type of finish, you won’t need to worry about the color fading over time.

Installation

Installation of metal roofing is fairly easy but still requires knowledge and skills. It is especially important to properly waterproof around penetrations, skylights, chimneys and roof/wall junctions. I have heard installers say that new metal roofing can be installed on top of your existing roof, but I cannot imagine why you would want to do that. If you can afford a metal roof, you can certainly afford to do it right. The material is lightweight and won’t cause problems to your existing roof structure. This fact can save you some significant money during the installation phase.

I admire homeowners who make the choice to invest in metal roofs because of their durability, so be concerned if some installers only offer a one-year guarantee on workmanship. This is at odds with metal roofing’s exceptional material warranties and promise of durability. TheMetal Roofing Allianceoffers courses for  metal roofing installers and contractors to make sure their work stands up to the durability of the metal material, and the test of time. By using proper installation practices your contractor should be offering workmanship guarantees that are more commensurate with a lifetime roofing material. Here are some examples:

 

Use compatible accessories

An expensive metal roof can be ruined by using cheap or incompatible trim, fasteners, and accessories. Using galvanized materials or fasteners on a galvalume roof, for example, can cause irreparable corrosion and oxidation, compromising the quality of the panels and shortening a metal roof’s life. This is caused by poor planning or laziness because it only costs a small amount more for proper trim, fasteners, and accessories that are compatible with the metal roofing material. The long-term assurance of reduced call-backs… and even better, satisfied customersis well worth the trouble. 

 

Install with water runoff in mind

Use roof flashings and curbs made from aluminum or stainless steel that are most compatible for metal roofs. Galvanized flashing is inferior, won’t last as long and can actually cause corrosion damage. If using galvalume flashing, minimize and check seam welding as this can melt the material’s protective coating. 

Use well thought-out flashings and under/over curbs. Make sure you plan for proper clearance in order to give water some room to run off and avoid pooling (a good rule of thumb is a minimum of 12 inches between panel ends and the diverter on the upslope end, and 6 inches between the curb’s sides and panel seams). For big curbs with a heavyweight load, be sure you have proper structural support underneath. Demand use of curbs around chimneys, caulking alone will not hold over time to prevent leaks.  

 

Penetrations

For metal roof plumbing penetrations, do not use standard residential pipe jacks or those made for membrane roofs. Use a pipe boots made to last, from galvalume or aluminum.

Move the penetrations to miss panel seams and avoid blocking the flow of water. If other trades need to make penetrations in the roof (like HVAC), be sure they are supervised by the roofer and coordinate the location and method so that only proper techniques and materials designed for metal are used.

 

Contractors with the proper training should be confident enough in their product to offer workmanship guarantees that make sense. The value of a fine metal roof deserves that.

More

Here are even more benefits for homeowners who choose this material.

Energy

A metal roof system will help lower your energy bills. During the summer, it can reflect radiant solar heat that helps cut cooling costs. During the winter season, it will shed snow and ice off the top.

Functionality

Most metal roof varieties only weigh 50 to 150 pounds per 100 sft. This is the reason it can be installed over the top of old roof systems. There’s no need for additional structural support as the material is so light.

Sustainable

Roof metals, zinc, steel, copper and aluminum are some of the most durable and recyclable materials on the planet. If you decide to get a new one, you can even recycle it when you’re finished so there will be little waste at the end of the roof’s useful life.

Choices

The variety of metal roofing available caters to customers with different preference in price and style. You can choose between zinc, aluminum, copper and galvanized steel in many shapes and colors. Whatever you choose, you can count on unmatched longevity.

Aesthetics

Best of all, metal roofing looks great! A metal roof can make any home more attractive and an attractive home is a more valuable home. Plus, it’s much more fun to come home to every night. This alone is a great reason to choose a metal roof.

Summary

The up-front cost of my standing seam metal roofing was slightly higher than lesser roofs but when factors like durability, maintenance, life expectancy, energy savings, low weight, ultra-sustainability and good looks were considered, it was a total bargain.
The only problem we had was with the protective film applied by the factory. Because of scheduling issues, the roof material sat on site for several months prior to installation. When it came time to remove the protective film, it would not come off so some of the metal panels actually had to be replaced.

Once installed you will have a beautiful roof to protect your home for 50 to 70 years and perhaps even longer.