advice on running wires from attic to basement?

[purbeast0]

i've been running wire all day today and have had luck so far. however all of this wire so far is going from an upstairs closet to other rooms in the upstairs. i simply ran them into the attic and snaked them into 4 rooms. that is all done and came out fine.

now my last place to run wires, and the most important, is my basement where my entertainment center is.

this is a 4 level split level. the top floor is the 4th floor, where the wire is starting, then going into the attic. i'm trying to get the wire to the 2nd floor that is in a utility room that is right under another room and a wall surrounding it, and want to run it from there to the back of the drywall where my entertainment center is on the other side.

here is pics of the room on the 4th level, where i'm positive the wall and closet, as well as the room, are above the utility room:

http://i.imgur.com/qhJPz.jpg
http://i.imgur.com/3rVcx.jpg

don't mind the mess there is insulation everywhere up there right now.

and here is the utility room that is directly below that portion of that room:

http://i.imgur.com/YxFBJ.jpg
http://i.imgur.com/JH93q.jpg
http://i.imgur.com/xCqTf.jpg

the problem is, i don't know exactly WHERE the walls are on the basement, so i don't know where to drill up from the basement into the wall, and then snake wire down through the wall into the basement through that hole.

does anyone have any tips on how i can figure this out?

worst case scenario is i drill through the hardwood floor in the closet into the utility room, but i would REALLY like to try and not do that unless that really is my only option.

 

[mshan]

If ultimately you can't figure it out, try calling some companies that install security systems.

They may have employees that run wire as a side job when they are not on company time.

Probably can search around YouTube too.

Few links I've bookmarked over the years:

- http://forums.anandtech.com/showthread.php?p=28866715#post28866715

- http://answers.yahoo.com/question/index?qid=20080728144605AADjwNe

 

[EagleKeeper]

Find a point of reference that you can use.

A window or door that you can measure from.

 

[purbeast0]

i just realized something that could work too.

there is an air duct that is in a wall upstairs pictured here:

http://i.imgur.com/rfpHO.jpg

and it comes out in the utility room here (on the left)

http://i.imgur.com/z2yso.jpg

would drilling a hole in the attic next to it, then one down in the basement next to it as well, work? there is some yellow sealant around there and not sure why exactly.

but to those experienced in this, does this look like the best option?

also i've been using 1" bits to cut through the wood and could fit 6 cables in them snuggly. would using a 1.5" hole be okay for this since i'm running 8 wires, or could that mess with the structure of the wood beams?

 

[EagleKeeper]

I would worry about putting a 1.5" hole in a load bearing beam.

Might be better at that point to have individual holes for each wire a couple of inches apart

If you can run the wire down without putting a hole in the air duct; try it.