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TOPIC: General Discussion

Underlayment

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I am in the process of building a new home and I'm trying to decide on which panel/underlayment to use. I would like to use a consealed fastener system with the self-adhering underlayment. It seems that the manufacurer's sales representatives are unable to tell me if this is the correct system. Help. Can you please tell me what I need to use for underlayment with this type of panel?
Guest User

2/23/2006
Hi there. I am assuming you are referring to a concealed fastener standing seam. In that case, you need to have an underlayment with a smooth (non-granulated), non-asphaltic top surface so that you will not have any problems with the top of the underlayment either sticking to or rubbing against the back of the metal panels. Frankly, if the roofing manufacturer cannot answer this question, something is very very wrong. I would look for another manufacturer because if they can't answer this, then chances are they alos do not know about the sorts of quality materials it takes to produce a wuality metal roof either. Todd Miller
Todd Miller
Isaiah Industries, Inc.

2/24/2006
Most metal roofing Mfg's require a 30lb felt for underlayment, you might also consider an ice & water product, depending on your area of the country. I would recommend some sort of venting when using ice & water ( peel n stick ) to cover an entire roof. Without proper venting in the attic it will condensate. 30 lb felt will allow your roof to breath, to a degree, but venting the eave and ridge would be the best choice. Mike
Guest User

3/3/2006
I agree with Mike's venting comment but would go one step further to emphasize the need, in most construction, for good attic ventilation, with intake and exhaust, in all attics, regardless of the roof covering. Todd Miller
Todd Miller
Isaiah Industries, Inc.

3/4/2006