How to Run Wires in Existing Construction past horizontal stud/fire-block

I am trying to run a couple of ethernet cables (Cat 5e) to my existing thermostat location in my home in order to install a network enabled thermostat and remote temperature sensors.  My home is 2-story stud/drywall construction and I have basement.  There is a fire-block (horizontal stud) between the floor and the thermostat location.  I know this because I saw it during construction.  I have previously replaced the thermostat wire - putting a 6-condutor in place of the original 4-conductor.  The hole through the fireblock was barely big enough for the -4, and the -6 was an extremely tight fit.  So there is no room to use the existing hole.  I could try to go up through the attic, I suppose, but that would be extremely complicated.

My question is, what is the easiest/best/cheapest way to run these wires to the existing thermostat location - past the horizontal stud?

Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

The easiest thing to do would be to cut a hole below the horizontal fire stud - big enough to work in.  Remove the old wire, then use an auger or some kind of tool to enlarge the hole enough for your larger wire to pass through, then run your new wire up from the basement - grab ahold of it with your hand or some tool and feed it through the hole to the thermostat.  Then patch the wall and paint.
Robert Sutton JrSenior Network ManagerCommented:
Well,  I have a few questions??
1) Will you be using the existing wire still or will that be replaced once the new wire is installed?
2) Is the thermostat on the 1st or 2nd floor?
3) You can try to run a home-run through your attic if you are attempting to access walls on the 2nd floor. You wont be able to access 1st fl walls from the 2nd floor no matter how much you try without causing damage. a GOOD RULE of thumb is: fishing walls on the 2nd floor is usually easier from the attic. Fishing walls on the 1st floor is typically easier from the basement.
4) The simplest solution would be to use the existing wire to pull through the new wire(s) right from the back of the "Existing" thermostat and pull DOWN towards the basement..... Or vise versa.... Pull up from the basement.....

I threw a few Ideas out there... I hope you can use one. Let me know if there are any other questions you may have.....
Robert Sutton JrSenior Network ManagerCommented:
For what its worth:
Typically your standard thermostat wire is insulated and thicker (Diameter wise*) than your typical ethernet, CAT5, etc...Its all 8-condutor but its alot thinner than the thermostat wire...
Powerful Yet Easy-to-Use Network Monitoring

Identify excessive bandwidth utilization or unexpected application traffic with SolarWinds Bandwidth Analyzer Pack.

egladnerAuthor Commented:
To answer The Warlock's questions above...
1.  Yes, I will be using the existing wire.  The Cat5 I need to run is additional to the normal thermostat wires.
2. The thermostat is on the 1st floor.  
3. Actually, my home is 1.5 stories.  The location of the thermostat is in the part of the house that is just a single story, so I could access it from either the basement or the attic.  I could go up through the attic, but then I would need to run down through another wall somewhere to get back to the basement where my hub is.  I was trying to avoid having to do that, since it could lead to further complications.  But right now it's either that or busting a hole in the wall - unless I get some other suggestions here.
4. That's what I did when I replaced the 4 conductor with the 6 - I used the 4 to pull the 6.  But in this case, the 6 needs to stay there and I need to add the cat5.
Your going to need a long flexible drill bit,  heres a picture of what I am talking about,

Using one of these allows you to drill holes through the horizontal stud in the wall from the existing hole for the thermostat.  With a long bit you may be able to drill right into the basement.  The drill bits also double as a wire pull so you can remove the drill and pull the bit right through with a wire attached.  You do need to be sure that there are no electrical wires or pipes in the space you are drilling through.

It is also possible to drill up from the basement and down from above then do some fishing.  Either with new holes or enlarging the existing holes.  Feed some wire in one hole and use a fish tape or even just a old coat hanger straightened out with a small hook on one end to catch the wire and pull it through the second hole.  If you make new holes you need to be very careful that you drill up into the wall and not through your floor.  You will still need to use a flex bit to redrill the horizontal stud through the hole where the thermostat is mounted.  

You would probably need a 1/2" hole for all 3 wires but a 3/8" may be okay for a pair of Cat5 wires just be careful not to get any kinks.  The long flex bits are not cheap but they save a ton of time.  You can likely get these bits from local electrical supply stores or places that cater to contracters.  

Another route is to go up to the attic then come back down through a door frame.  Just remove the moulding from one side and drill up to the attic and drill down at the bottom of the door.  Then run the wire down the space between the jam and the frame and replace the moulding.  You would likely still want a flex bit long enough to drill up from the thermostat and door frame to the attic.

There should be no reason to have to damage any walls for this run - just be careful with the long bits.


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
He asked for, "easiest/best/cheapest way to run these wires".

IMHO, cut a hole in the wall, pull the wire out, round out the hole to make it larger, reach in grab the wire and push it through the hole - is pretty easy and cheap.  Yeah, a little labor repairing the wall.  But meets the criteria.
I really think that calling the patch job 'a little labor' in glossing over just how much extra work this creates to drop a couple wires down the wall.  Probably why the poster asked for other suggestions.

While patching large holes in drywall is not 'hard' it is not 'easy' to do well - meaning done so it does not show.  Unless the tools and materials are handy it is not necessarily cheap either.

Here's a link for the drill bits - $25-30 range,  a local store would likely be a bit more.  Well worth the cost for the mess it saves.

egladnerAuthor Commented:
Thanks for the input.  I agree, patching a hole in the wall may be easy - doing it well is not.  That was the obvious solution, but not what I was looking for.  Thanks for your help.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.