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Metal Roofing Advice

riverat's picture

I live in a 1940, single story, single hip roof, 1100 sq. ft.  tabby home in coastal Georgia, but not directly on the water. It is my primary residence.  The roof sheathing is solid substrate (decking).I have a few questions about replacing my asphalt shingle roof with a properly installed, Gavalume, metal roof
As far as profiles I was thinking of “R- Panel “or “5V Crimp”. Typical of the older cottages down here, there is a slight waviness or imperfections to the roof. Would an r-panel   sheet roofing hide blemishes better than a 5v-crimp? The ribs of an r-panel  have 11/4 “ tall ribs and 36” panel coverage and are reportedly good for lower sloped roofs. 36 inch coverage would require fewer holes and screws since most 5v crimp has 16 inch coverage.
Or, would 5v crimp be a better sheet roofing choice?
Can Ice & Water shield be used as underlayment? Can metal roofing be installed directly on the Ice & Water shield?
Is 24 gauge metal roofing less prone to “oil canning” than 26 or 29 gauge roofing?
Stylistically, and given my geographical location, which roof style do you think would be better?
Unfortunately, standing seam roof style is more than my budget can afford.

By the way,  I will be removing the exsting skylight as shown in photo.

Your thoughts would be appreciated,
Bill Hilton

The two profiles that you are (post #208069, reply #1 of 1)

The two profiles that you are considering are exposed fastener roofs. Most exposed fastener roofs will develop a leak at some point and the lower the slope, the greater the likelyhood. That being said, putting I&WS under the entire roof would probably be a good belt and suspenders option. However, you would need to use NON-granulated high temp peel & stick underlayment. The granuals will abrade the finish on the back of the panels.

Both of the profiles that you are considering have regular ribs or striations, so oil canning should not be an issue, no matter the gauge. Are you after a raw galvalume finish or are you considering a color? If you're after a color, avaoid the low cost polyester finishes and opt for Kynar instead. I've seen much polyester finish failure.


Are you DIYing this installation? Concealed fastener standing seam might not be out of reach if you are. If you'd like to contact us and discuss it, click the link below.