large vent flashing

john J
I posted a message a day or two ago, but it did not show up. Here is part of that: I am looking at installing metro roman (or decra villa) tiles. The question is how to flashing a large vent opening (eg 6" or 8" or even larger). The installation manual only says that for small pipes (eg 1-3") first use an under pan, then the pipe flashing, and finally the tile. For large opening, it merely says that no under pan is needed. Can any one describe how a large vent should be flashed?
Dick Bus
I would recommend that you contact Metro directly. Their technical people will be able to help you.
Guest User
The base flashing could be coated to match the Metro color you choose but i think your refering to Smart Accessories. I think the 1"-3" reference is related to the Smart Accessories. The base flashing, when you using the Smart Sleave, is coated to match the roof color and is also designed for the Smart Sleave. It is not available in sizes above 4". Any vent flashing / jack larger than the 4" would not be able to utilize the Smart Sleave and base system, because Metro does not make them in the larger sizes. I use standard vent flashings on all the Roman installs, if Metro wants to make Smart Accessories to cover all vent sizes we come accross then, i would be more inclined to use them. If you have a lot of jacks on a section of roof where some are beyond the size limits of the smart sleaves, then the jacks will not look the same. The Smart Sleaves have a much larger profile than a standard jack of the same size, they will look completely different than a non Smart Sleaved jack. I would just use a standard jack, chip the caulking to match the roof color and then paint the remaining pipe to match the roof color. Andy
Guest User
Thanks for the response! Andy, I am not talking about the Smart Accessories. I am not planning to use them (not even for the 1.5-3" pipes). I am going to use their aluminum base flashing (for easy working). The question really is: How should I install it to "prevent leaking" for the large vent holes? Should I install under pans first, then the aluminum base flashing and then the regular tiles (just like the metro installation video except not using the smart accessories)? or under pans are not needed. Eg, if no under pans are needed, then should I bend the 3 sides (except the lower side) of the base flashing up or not. I know you have done a lot of this, I would appreciate if you could describe it in detail. I have another 2 questions: a) valley metal: metro has a 7" valley and I would like to use it (batten-less install). I was told that 2x2 battens should be put on both sides of the valley and the valley be fastened to the batten. If this is the case, it seems to me the tiles will be bent up along the battens at the valley, then you will use barrow caps to cover the battens on both sides of the valley (leaving an open valley). Am I misunderstanding it (the person who told me this is on vocation now, and the distributor does not know the answer)? I wan to have a closed valley (ie tiles cover the valley metal). Must I use the wide valley metal just like the metro installation video? b) Sun tunnel light. The 14" circular tunnel light seems popular. Do you know how to install it with villa tiles without using the extra tile flashing kit provided by the tunnel light manufacture ($130)? The sun tunnel comes with a flashing piece just like a vent base flashing. Thanks, John

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