Energy Star Water Management Requirements

I am having difficulty understanding a particular requirement of the Energy Star Builder requirements.

The National Water Management System 3.3 requires: self-adhering polymer-modified bituminous membrane at all valleys and roof deck penetrations.

Footnote 16 states: As an alternative, any applicable option in 2009 IRC Section R905.2.8.2 is permitted to meet item 3.3…In addition, any option in 2009 IRC Section R905.13 is permitted.

Am I interpreting it correctly that the Footnote, allows you to meet minimum code as an alternative to the preferred method?

They want you to ensure the valleys of a roof do not leak. ICE&WATER membrane (per 3.3) is one way to accomplish it. They then refer you to the code and tell you that other approved methods, as per code, is okay with them, too.

In order to understand their requirements you need to have a solid knowledge of construction methods. Start with step A not step C :slight_smile: Their requirements are not for a novice but for an experienced builder. Best of luck!

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My point wasn’t very clear. Why would there be a requirement for the Builder to meet a higher standard, if they accept the minimum as an alternative? Does not that defeat the purpose of the higher level of protection the Energy Star standard offers? Am I understanding the footnote correctly to accept minimum code as the alternative?

“Self-adhering polymer-modified bituminous membrane” is not exactly a “higher” standard, it is listed in the same [minimum] code the footnote 16 refers to. EPA chose it as its minimum method, not the other way around. There are other ways to line a valley, are you familiar with them, did you read the code they are referring to?

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Welcome to our forum, Alfred!..Enjoy! :grinning_face_with_smiling_eyes:

I had read the code. After researching material costs, I estimated the Energy Star method to be roughly 3x the cost as minimum code. That is what has me asking the question. I am in an area which does not require Ice and Water Shield by historical temperatures, so basic felt is compliant for an Energy Star and Indoor Air Plus home.

Why would a builder meet the Energy Star option when for a great deal less money, they can meet minimum code and still achieve Energy Star compliance.

You keep adding information… what is the full story? are you a home inspector? what is the reason for researching this information?

What exact roofing application are you referring to? where did you read (cite the source) that you can just use basic felt in a valley?

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The full story is:
I am earning my home inspector license. I retired from the military 4 years ago where I inspected commercial oil tankers, chemical tankers, and liquified natural gas ships for 23 years. I currently work for a builder of single family homes (primarily) which are Energy Star and Indoor Air Plus certified. I am currently going through the entire Energy Star and Indoor Air Plus certification checklist for my own education and benefit.

I am asking the question, because I want to ensure we meet the Energy Star minimum. I am not looking for the best way to do it, I am trying to understand the Minimum allowed under the Energy Star program.

Hopefully, that is transparent enough to gain some assistance in working through my lack of understanding on why an Energy Star standard would allow the builder to default to minimum code.

My sources:
R905.2.3 - Underlayment - must meet ASTM D 226 Type I

ASTM Website: D226- This specification covers asphalt-saturated organic felt used in roofing and waterproofing. Two types of asphalt-saturated felts are presented: type I - commonly called No. 15 asphalt felt,

Table R301.2(1) (h) - jurisdiction does not have a history of ice damming.

R905.2.8.2 - For closed valleys (valley covered with shingles), valley lining of one ply of smooth roll roofing complying with ASTM D 6380 and at least 36 inches wide (914 mm) … shall be permitted.

ASTM D 6380 - Standard Specification for Asphalt Roll Roofing (Organic Felt)

While both can be made from an organic felt, an asphalt based roll roofing and felt underlayment are not the same product. Also, an underlayment required for roof covering is not the same as a lining required for a valley (the two have different requirements).

Also know that unless the manufacturer of the asphalt shingles approves a roll roofing as a lining in a valley where their product is installed, not only would it be against the code, it would also void their warranty.

Like I noted, you started with a C instead of an A.