Holes in Joist

27col

Can somebody please explain the logic of preventing the use of a hole already drilled in a joist.

dave82_2

Yes the current and holes drilled in error are too near the top so doesn't meet the regs. If I then nail the floor board down I might go through the cables!!!

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andrew-b

So it's more important the electrics are safe but doesnt matter too much if your floor collapses...makes perfect sense :rolleyes:

wealdroam

Plugging the holes will potentially restore some of the weakness too.

Gloomendoom

wealdroam wrote: »

Plugging the holes will potentially restore some of the weakness too.

I don't think you mean what you wroted!

diable

andrew-b wrote: »

So it's more important the electrics are safe but doesnt matter too much if your floor collapses...makes perfect sense :rolleyes:

If the microwave, TV and kettle still work then whats the problem? :whistle:

greenface

:T

andrew-b wrote: »

Test it by threading a rope through the joist and hanging the apprentice from it?!

:T

my thoughts too

dave82_2

Cheers All,

They have said verbaly it isn't an issue I will ask the sparc to sign the following.

"<company name> aknowladge that during the rewire a number of holes were drilled in error that do not meet bulding regulations for drilling holes in joists.

In our opinion this will not affect the integraty of the joists or cause any future problems in the area of the errounous holes.

Signed

x"

If they really don't think it is an issue they won't mind signing!

Cheers

Gloomendoom

I'd run it through a spell checker first.


Oh, and the kiss at the end is probably overkill.

1984ReturnsForReal_2

Albert



Joined: 17 Feb 2004
Posts: 698
Location: United Kingdom
Thanked: 1 time
Posted: Tue May 16, 2006 6:19 pm Post Subject:
Could you please detail the source of these figures?
According to BS7671, 522-06-05 (brown book), and OSG page 52:
The cable should be installed in a "position that it is not liable to damage by contact with the floor or the ceiling or their fixing. Unarmoured cables passing through a joist shall be at least 50mmfrom the top or bottom as appropriate or inclosed in earthed steel conduit"...etc.
1. Max dia of hole 0.25 x joist depth
2. Holes on centre zone between 0.25 and 0.4 x span (I think that this is your 25% to 40% figure).
3. Holes in the same joist should be at least 3 diameters apart.

http://www.diynot.com/forums/viewtopic.php?p=353927#353927


In other words the holes should be at least 1/4 of the way [STRIKE]down/up[/STRIKE] across but no more than 40% across & at least 3 hole widths apart.





Edited: Point taken from below