Published on October 9th, 2013 | by Henri0
Metal roofing usually should have ventilation
Q. I am nearing completion on a new house that I have built myself and am interested in installing either metal roof shingles that are stamped and colored to look like slate, or metal roof shingles that look like conventional, colored, standing-seam roofing installed in 5-foot or 3-foot lengths.
The roofing would go over stressed-skin panels that are currently covered with deteriorating 30-lb. roofing felt. The objective is an attractive, long-lasting roof that I can install myself to save money. I have a number of questions:
- Do you recommend this type of roofing or is there a better alternative?
- Is ice and snow shield on the peak, in valleys, around penetrations, and over the bottom three feet of the roof adequate? (I’ve been seeing roofs that are completely covered with this membrane before shingles are installed).
- Is any strapping required or can the roofing go directly over the ice and snow shield and roofing felt?
- Anything else I should know?
A. Metal roofing is generally a good choice, although some of the manufacturers of the types you describe will sell only to licensed contractors.
I would be concerned about installing metal roofing directly over stressed skin panels without some ventilation between the panels and the roof deck. These panels are so energy-efficient that unless the metal roofing is white, solar heat may distort it. However, on that issue, it is worth checking the recommendations of the manufacturer.
An ice-and-water protective membrane should be installed in all the locations you list except at the ridge, if a ridge vent is used. The practice of installing an ice and water protective membrane all over the roof is seen more and more. It is costly but it should prevent any leakage problem if there is some failure in the roof covering itself.by