going over shingle roof

i have a dimensional shingle roof on now that is in decent shape but want something thats going to last forever. ive seen where you can go ever a shingle roof with metal but wondered about where the screws go in sinking the metal panels in and creating a indentation in the panels. ill be using 20 gauge metal panels form ABC roofing supply, SELECT 40 7/8" wide rib. they overlap, not standing seem. is going over a existing shingle roof going to cause me problems with the looks of the panels.		paul orne 9/10/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19817/find/
It will not create the flattest substrate to be certain. You would be well advised to either strip the roof or go over furring. Can't hurt with some additional convective air movement behind the panel for cooling either.		Eric Novotny An informed customer is the Best Customer! 9/10/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19818/find/
the problems i see with furring strips is walking on it. step in between the strips and instant bend.		Guest User 9/10/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19819/find/
Depending on the spacing, not necessarily. This is also why you don't want someone walking your roof that doesn't know the construction or proper technique.		Eric Novotny An informed customer is the Best Customer! 9/11/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19820/find/
if you are interested in a roof that will last for ever. you need to consider the entire system. a 20 gage panel is a pretty beefy panel that will have great spanning capabilities. I have never heard this heavy of a gage being used for the residential market. I would recommend stainless steel fasteners. Flashing details are very important, make sure you review them before the project is started. Underlayment and ventilation are also important. Using a roofing system from a member of the Metal Roofing Alliance will be give you a level of comfort as all of us have agreed to only promote quality products for the residential market.		Dick Bus 9/26/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19821/find/

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