Choosing The Right Metal Roof for Your Home

I am always amazed at how roofing sales people try and push their 'one size fits all solutions' to homowners.

The are many excellent options when it comes to metal roofing like metal shingles, metal tiles ,metal shakes and metal slate. There are roll-formed metal solutions that come in a variety of architectural syles like standing seam, roll-form tiles, roll-form shakes and roll-form steel shingles. There are exposed fastening systems and and there are concealed fastening systems. There are different gauges and thicknesses. There are steel options and there are aluminum options. There are econo-coatings and there are premium coatings. Frankly theres a lot to choose from when it comes to metal roofing, and there are also important budget considerations. 

Its impossible for any one metal roofing product to address all the issues you want to be considering when investing in a new metal roof.  The right choice for your home depends on the age of your home, how it was constucted, how it was ventilated and how it is insulated.

I will keep this short and simple.

THREE IMPORTANT  CONSIDERATIONS WHEN CHOOSING A NEW METAL ROOF

1. Is your roof level?  A roof that is not level immediately discounts the use of metal shingles unless you are OK with a significant investment in sheathing deck replacement or having your new metal roof following the sagging contour lines of your existing roof. A sagging sheathing deck is an indicator of a potentially damaged plywood or OSB roof sheathing deck. This situation is common in homes built in the 1960's and 1970's when OSB came to market and ventilation was not a swell understood or practiced as it is today. A sagging roof deck in homes built in this era is likely a result of inadequate insulation or ventilation. Regardless of the cause of the roof sagging, given that most metal shingles are screwed directly in to the roof sheathing deck, you need to be aware that roofing screws securing your new metal shingles could ventually pull loose with daily expansion and contraction. A new metal roof heats and cools on a daily basis as the sun heats up the metal during the day and it contracts at night when it cools down.  The solution for a sagging roof is to install a double strapped metal roof  that provides above sheathing ventilation and allows for the vertical strapping to be shimmed prior to horizontal straps being applied to create a level roof.  Vertical straps are applied directly to the trusses, meaning that the weight bearing load of the new roof is sitting on structural lumber, not a sagging OSB or plywood sheathing deck. A sheathing ventilated roof damatically improves air circulation and ventilation, aloows for roof levelling and offers energy savings that can not be realised with with metal shingles.

2. Are You Experiencing Ice Damming?  if you are experincing ice damming, this discounts the use of metal shingles.  The only viable  solution for solving ice damming above sheathing ventilation. A double strapped roof creates a thermal bridge that prevents the snow from melting due to attic heat loss. I have been called out to countless homes with major ice damming issues that recently had new metal shingles installed. The homeowners were lead to believe that snow would simply slide off the new metal shingles. Bottom line, if your roof experiences ice dams in Winter with asphaly shingles, metal shingles wont solve

3. How is your roof ventilated?  If you live in an older home built in the 1920s - 1950s then its likely that your home was built without soffit ventilation. Despite the fact that there is often very limited ventilation in these roofs, I generally don't see any sagging in these roof deck because they were built using 1"-2" planks made from fir or cedar, unlike the homes built with OSB in the 1960's and 1970's.  I have seen many roofs from this era effectively using both metal  shingles applied directly to the roof sheathing deck as well strapped roll-formed metal solutions. If all you care about is  aesthetics, all metal roof options are open to you. However, if you want to improve indoor comfort levels in your home, especially the upstairs living areas and improve roof air circulation, a double-strapped metal roof solution is the way to go.