Home>Discussions>HEALTH & SAFETY>Floor Joist Structure Compromised...Possibly ???
8 posts / 0 new
Last post
gmac80
Floor Joist Structure Compromised...Possibly ???

A cable company technician installed a new cable line. He cut out the hole for the wall plate in the drywall and drilled down within the wall. When he drilled he went down through a 2 x 8 floor joist. (Actually two joists that are sandwiched together.) So he entered somewhere at the top of the two joists and the cable comes out in the middle (4 inches from the top and bottom--middle area of boards) and at an angle of 110-120 degrees.) Does this pose any structural problems for my floor? If so, how do I know and should I call a contractor to inspect it for the possibility of adding stability. Thanks!

dj1
Re: Floor Joist Structure Compromised...Possibly ???

It all depends on the diameter and location of the hole. Usually cable guys know where not to drill.

Google 'code for drilling and notching joists' - and you'll get valuable info about this subject.

HoustonRemodeler
Re: Floor Joist Structure Compromised...Possibly ???

Generally, drilling a 3/8" or 1/2" hole into a 3" joist will do very little harm if any.

Worknot
Re: Floor Joist Structure Compromised...Possibly ???
gmac80 wrote:

A cable company technician installed a new cable line. He cut out the hole for the wall plate in the drywall and drilled down within the wall. When he drilled he went down through a 2 x 8 floor joist. (Actually two joists that are sandwiched together.) So he entered somewhere at the top of the two joists and the cable comes out in the middle (4 inches from the top and bottom--middle area of boards) and at an angle of 110-120 degrees.) Does this pose any structural problems for my floor? If so, how do I know and should I call a contractor to inspect it for the possibility of adding stability. Thanks!

you stated floor joist and sandwiched together. which is a sign that maybe a double joist which is used to carry extra weight or to head off a opening or cantilever section of the house(bay windows or a deck. A hole 3/8" would normally be ok, even at an angle, but you better check. I think it is 2" from either top or bottom

Sombreuil_mongrel
Re: Floor Joist Structure Compromised...Possibly ???

I think OP is stating that the hole was drilled down vertically and hit a double joist instead of the bay between joists. So the damage is minimal and not structurally significant, IMO. Unless he was using a 3" bit.
As far as cable installers knowing what they are doing? Give me a break; one of them drilled up through my sister's PVC shower pan liner! They had to pay for replacing the liner and the tile.
Casey

dj1
Re: Floor Joist Structure Compromised...Possibly ???

Casey,

There are moron installers in every cable company, but most installers, who want to keep their jobs, follow the guidlines.

The same goes to other trades: a driver who backs the company truck into a newly installed flower bed, a drywaller who drills into a copper pipe, a cabinet installer who breaks floor tiles...
We've seen them all. All accidents are covered by the employers and hurt the bottom line.

Worknot
Re: Floor Joist Structure Compromised...Possibly ???
Sombreuil_mongrel wrote:

I think OP is stating that the hole was drilled down vertically and hit a double joist instead of the bay between joists. So the damage is minimal and not structurally significant, IMO. Unless he was using a 3" bit.
As far as cable installers knowing what they are doing? Give me a break; one of them drilled up through my sister's PVC shower pan liner! They had to pay for replacing the liner and the tile.
Casey

sounds like we need a picture, didn't sound like it grazed it.
-"So he entered somewhere at the top of the two joists and the cable comes out in the middle (4 inches from the top and bottom..."-that's a 4" gash in that board. we all are just guessing until we see it.
everyone has had bad day. some just have them more often then others :)

Pat Dagnan
Re: Floor Joist Structure Compromised...Possibly ???

who want to keep their jobs, follow the guidlines.

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.