For Professionals | Member Login
Find a Professional
Sign Up Log In Add New Topic

TOPIC: Leaking

Bad Valley

Return to Leaking

Return to Archive

Return to Forum

My house has a vertical panel metal roof with a bad valley. The cross-section is an "M" with the two ridges about 23 feet apart. The valley of the M starts at the back of my chimney and runs nearly level for about 25 feet before one of the pitched roofs ends. The contractor appears to have put a rubber sheet about 3 feet up each side of the valley (underneath the metal panels). Though the valley collects dirt and debris, the rubber may be working along the length of the valley, but it is leaking at the end by the chimney. I don't see any easy way of correcting this nearly level (horizontal) valley -- can you suggest anything extra to do at the chimney (flashing, sealers, sloped pieces?) to stop the leak? Thanks, M. Robertson
Guest User

7/26/2004
I am not sure I am envisioning exactly what your roof is like but, when flat valleys exist, I always look for ways to cricket or pitch them to get away from the flat situation. If you wish, please send me some photos. [email protected]
Guest User

7/27/2004
I'm sure you're right. In this case it seems that a triangular piece would be necessary to raise one end of this flat valley. Take a rectangular piece of paper and fold it in half to make it a V cross-section. Then fold each leg of the V back on itself to form an M cross-section. There you have my situation -- two peaked roofs side-by-side, with a valley formed where they touch. Not a correct situation, I'm sure. If you lay a narrow triangle in the valley, it looks like it would shed water toward the apex of triangle. Seems to me to implement that solution, I'd have to trim the roof panels in the valley back on a shallow diagonal and insert this triangle underneath their edges. It would have to have some wood braces tied in underneath, of course. Not a particulary easy solution to implement. That's why I was wondering what I should look for at the junction of the valley and the chimney. I believe that is where my leak is. Thanks again, M Robertson
Guest User

7/27/2004