Exterior window trim help

[Brian Tax]

I am putting in new window in my 1979 split entry house. I wanted to use 5/4 x 4 exterior trim around the windows. I am concerned ends of the cedar channel siding would not fall on a stud, since there are 2 studs on the sides of the rough opening for a width of 3”, but the trim would be 3 ½”. I think this might be ok, if the sheeting is plywood, but only the corners of the house have plywood sheeting. The middle of house has are some kind of fiber board sheeting that will not hold fasteners well. One option would be to use 2 ½” trim on the sides only and 3 ½” on the top and bottom or 2 1/2” on all four sides of the windows. The windows are white vinyl horizontal sliders. Any other thoughts, ideas or opinions on the 2 ½” trim width would be greatly appreciated. Also is there a standard or common trim style or design you would recommend?
Happy 4th, Thanks, Brian

[Jerome Stanek]

how thick is your siding? Can you dado the back of the trim to fit over the siding

[Brian Tax]

The siding is 3/4", I thought about a dado, but I am not sure if I want to go down that road, but it is an option.

[Thomas Williams]

When I installed my windows I ran 5/4 X 4 board around the window nailing to the jack studs, header, sill and studs. Depending on where a stud was in relation to the end of the siding I used construction adhesive behind the cedar lap siding. I do not recall any stud being more than 8 inches from the opening though.

[Paul Girouard]

Trap it with a rabbit on the side of the exterior trim, the bottom as well. It's a much more weather proof joint as well.

You might look at using a wider and thicker head piece, say a 2x6 or a cut down one 1 1/2" x 5" net. with a 1/2" ear on either side. So the head piece is cut 1" longer than the measurement of the outside to outside measurement of the side casing / brick mold.


Similar to this look,

[Brian Tax]

Thomas,

Did you use the construction adhesive to bond the siding to the sheeting? What about the tar paper/building wrap between the siding and the sheeting.