Electrical Boxes, before or after sidin?

Hello. Just wondering if electrical box holes should be cut through the exterior sheathing before or after the siding is on?
Thanks
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Replies
We used to have them installed before the exterior finish because the electrician would come to do the rough in before the siding was on. Sometimes we would have to adjust the depth of the box. Maybe the bigger question is who do you want cutting the hole in the siding? The electrician or the carpenter.
Thanks. I'll be doing the cutting since it is on my addition and i'm the jack of all trades on this one.
It takes some extra time, but I carefully measure and locate trim blocks on the sidewall for outlets, lights and hose bibs. The blocks fall in one course of siding or two depending on the exposure. I like to use Azek so rot is not an issue. I also notch the bottom for the siding to go under and have a notch on top to catch the next piece.
Normally when we do a full reno, we just stick the wire through a hole in the sheathing, then apply the box after siding.
Family.....They're always there when they need you.
Thanks Guys for the tips.
Are are some options.http://www.aifittings.com/arliprod6.htmThis one is surface mounted afterwards.http://www.aifittings.com/whnew45.htmAnd this one is done before.http://www.aifittings.com/whnew13.htm.
William the Geezer, the sequel to Billy the Kid - Shoe
Thanks Bill.
Easier to do it after, especially if you have access to the back side. That way you can center the box opening in the exposure, with no chance of miscalculation. (Remember to figure in the top lip of the cover plate when placing the box near the top of the exposure, and also include any clearance needed to allow the weather shield to open.)
Thanks Dan. Thanks for the info. on centering.Makes sense.
We just went thru this one.
Our lesson learned for Next Time...
If the inspector requires the boxes to be mounted to pass rough electrical, OK.
Tell the Sparkie you want enough cable slack to move the box later. They have no idea where the siding will break.
Soon as Inspector signs and leaves, pull them all off and hang them on the cables sticking out, waiting for the siding.
When you get to that point on siding, you can install them precisely where you want them - like centered on a stick of siding, not on the edge (BTDT).
Our sparkies go the garage light mounts about 1" out of level left to right. Didn't show until that nice level siding appeared. Got to move the boxes under the worse conditions.
HO selected large carriage light fixtures with oval mounts spanning two sticks of siding. Had we known early, would have fabbed some rectangular mounting blocks, leveled those in and sided to and around these. Our work around was not bad, but it could have been better if decisions were made before, not after siding that section.
The ToolBear
"You can't save the Earth unless you are willing to make other people sacrifice." Dogbert
Thanks TB for the good advice.