Brett: With few exceptions, there is no reason the truss bearing on the 'header' makes a difference. Actually, what you're referring to is called the 'top plate'. A header is the beam that is laid above an opening like a door or window. The top plate is two layers of 2x4 laid flat accross the tops of the studs. They use two layers for two reasons: it makes corners and intersecting walls easier to join, by overlapping, and the joists, rafters, and/or trusses don't have to be directly over the studs (which is called 'stacking').

At the bottom of the wall is (you guessed it) a bottom plate, which is a single 2x4 laid flat. The studs stand on the bottom plate. What makes the job of snaking wires in an outside wall difficult is the insulation. A fishtape is usually required because it is stiff enough to push past the insulation batts. The inside side of the insulation is faced with a kraft-paper vapor barrier, so if you can keep the wires between the paper and the backside of the drywall, so much the better, but it's very difficult.

The second difficulty is drilling a hole through the top plates below a low roof, but it can be done, more easily with an angle drill. Just remember to think three-dimensionally, so you don't drill into the room or through the outside of the house.

Is it possible to go under instead? Unless your room is on concrete (referred to as a 'slab'), your crawlspace should be easier to use. Just remember the three-dimension thinking again, especially again on the outside walls. It's easy to find inside walls from underneath, if you know what to look for.

Email me directly if you need more help. I'll even give you my number if you need one-on-one help.

Larry

This message was edited by Larry Fine on 09/17/01 01:04.23.