Open Valley

[phil kaznowski]

Today I looked at an asphalt shingle roof with an open metal valley. The valley was a metal rib where not only the shingles butted directly into the rib, but there was an additional layer of shingles that ran parallel against the rib (screwdriver is betwen shingles)? I have never seen this configuration, is this correct?

Thanks,

Phil K.

[Jerry Peck]

The valley was a metal rib where not only the shingles butted directly into the rib,

That is called 'preformed valley metal' and that is the water diverter, and that is really called 'closed valley'. They make a preformed valley metal with two water diverter ribs which is called open valley as the shingles meet to the two water diverter rigs and the space between the water diverters is the "open valley" part.


but there was an additional layer of shingles that ran parallel against the rib (screwdriver is betwen shingles)? I have never seen this configuration, is this correct?

Depends on who you talk to ... everything I've seen on that says no (actually, it says to do it differently, it does not even show that - that is just some lazy person trying to save from cutting a bunch of shingles off properly).