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Architecture/Ice dam solution; construct new, vented, foam insulated roof on top of existing warm roof


I live with very cold weather and lots of snow. My roof has almost no ventilation. An old roof, in need of repair, a 10/12 pitch approx. 13sq.  2 small gable dormers. What economical and effective construction plan can work to construct a new, vented, roof on top of the structurally sound existing roof? My thoughts involve; tear off shingles, provide vapor barrier, install 2" foam panels, lag 2"x4" s flat on top of taped & sealed foam sheets at roof rafters below. 1/2" OSB 4x8 roof sheathing over 2X4s, ice guard, felt paper,drip edge, shingles. Add overhangs eve & rake, add vented soffit and ridge vent, result...a cold roof?

With a roof that steep (10/12 pitch), I would say that if you install two rows of ice and water shield at the eaves (manufactured by Grace), then most of your problems will go away.

I understand your difficulty in trying to provide adequate ventilation for an existing eave condition.

Adding 2" of rigid insulation (R10) is always a good move.  


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Richard Burton AIA


A combined total of 25 years experience with construction, architecture, and building code enforcement. Ask me about residential and commercial design. Ask me about design aesthetics, structural methods, and building something that will withstand severe weather conditions. Ask me my opinion about YOUR design ideas and I will tell you the merits of good design and challenge your thinking about practical issues. Ask me how to best find and work with your local architect and approach general contractors to get the most value for the least amount of headaches. You can ask me about improving your energy efficiency and things that are both green and practical. But don't ask me about solar panels and wind turbines unless you are currently paying your utility company 35 cents per Kilowatt. Otherwise the math does not justify the initial cost and return on investment. Ask me any building code question and how to get a building permit from the most difficult enforcement agencies.


Here in the midwest, we design and build "green" in ways that make sense. My construction methods prioritize weather resistance, ease of maintenance and durability. While a graduate student in San Diego, I taught drafting and history of architecture. After working ten years for other architecture firms, I have started my firm Arrow Architecture in 2008. More than half of my work involves commercial office buildings. But my portfolio of work also includes custom homes, residential additions, home remodels, and second story additions.

President-Elect of American Institute of Architects - Lincoln, NE

B.S. Architecture - (Interior Design) University of Nebraska Lincoln 1997 Master of Architecture - (Urban Design and Professional Practice) NewSchool of Architecture - San Diego 2004 Graduated Summa Cum Laude ICC Certified Building Plans Examiner

Awards and Honors
AIA Henry Adams Medal and Certificate

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