The lack of a Z could be an issue. Also, yes, condensation could be an issue.
A drawing of the ridge assembly or a picture would be helpful.
Is there any way you can email more information to me and/or call me so we can discuss please? My number is 1-800-543-8938 ext 201 and email me at todd@asktoddmiller.com
Todd Miller
2012-05-31 16:50:01.000000
Dear Experts
it's an 1920s old house renovated with a brand new metal roof. The roof doesn't have a z closure under the cap at the top.
The roof is not vented and we sprayed open cell spray foam between the rafters underneath
and created an open cathedral ceiling.
6" of open cell wasn't enough for me so 2 months after the roof was up I installed 2" R10 foam board XPS over it
and sealed it all up nicely with spray foam from a can.
After a recent thunderstorm with wind driven rain followed immediately by 90+ F and 90% RH water started to drip
in more than a dozen areas, mostly between the first two pink boards from the top. They are 2 ft x 8ft installed horizontally, so basically
the water was coming from the peak down up to 4ft where the foam boards are sealed.
The roof has high temp underlayment underneath but no vent gaps, all new.
I took a couple of pink boards down from the top and they are wet. The spray foam underneath dried after two days so it wasn't too bad. But those areas covered by the pink boards are still wet behind (water is still dripping), I guess I need to remove at least the top rows to get it all to dry.
Is the Z closure absolutely necessary, could it be the reason water came in? Could it be condensation?
Thank you for your help!
Savas P.
2012-05-31 16:36:37.000000
Hi Todd
thanks for the reply. You'll find pictures and lots of different opinions in this forum:
http://www.greenbuildingtalk.com/Forums/tabid/53/afv/topic/aff/14/aft/80244/afpg/1/Default.aspx
forum entry: "Help! Cathedral Ceiling + Icynene Moisture Problem"
I tried spraying water into the gap at the metal roof cap but either couldn't get enough water pressure to get enough water into the gap, or the roof isn't
leaking around that area
Thanks!
Savas P.
2012-06-05 15:52:08.000000
The fact that it was directly after a rainstorm and not during the heating season (assuming that this was recent) somewhat rules out condensation.
Eric Novotny
2012-05-31 22:23:51.000000
Its a leak.
Dana is a supremely smart guy and he knows his stuff backwards and forwards.
It is a bulk water issue.
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