# Installing exterior wall vent cap for bath exhaust fan



## joecaption (Nov 30, 2011)

#1 I would not use a galvanized vent, it's going to rust at some point.
#2 If that's you and the vent your planning on using, stop! You need a siding block first so the vent will sit flat.


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## md2lgyk (Jan 6, 2009)

Your bathroom fan has a 6-inch vent?? Must be one heck of a bathroom.


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## Ray_S (Oct 9, 2013)

Joecaption, thanks for your reply. My questions are about the choice of caulk or adhesives, and how to secure the vent cap without predrilled screw holes. I haven't seen any vent caps with siding block so I would not try that. The picture is from internet and not me, but the install and type of cap are similar.


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## djlandkpl (Jan 29, 2013)

Drill your own hole in the flange. Caulk is not enough. 

You don't need to use a siding block but you have to make sure you have a good seal around the bottom or wind driven rain will get in. The siding block will make it look better and make aligning the duct work easier. When you mount it directly to the siding, the duct connection is angled downwards.


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## Ray_S (Oct 9, 2013)

Dan, thanks for the advice. I will predrilled holes and screw it on. My siding is T11 type and a little different than that in the picture. In my case the cap will be attached to the wall flat so I am ok without siding block. Thanks again. Ray


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