Notches and holes in joists

[Dippy]

I see that in approved doc A 1992 there is clear guidance on cutting notches and drilling holes in joists. But in the 2004 version there seems to be no guidance at all. Is this something that I need to discuss with my LABC directly?

 

[Chivers7]

Refering to an onsite guide page 52 section 7 :

Maximum diameter of hole 0.25 of joist depth

Holes on centre line in a zone between 0.25 and 0.4 x span

Maximum depth of notch should be 0.125 x joist depth.

Notches on top in a zone between 0.1 and 0.25 x span
Holes in the same joist should be at least 3 diameters apart.


* All need mechanical protection or greater than 50mm from top/bottom

Hope this helps

 

[Dippy]

Thanks. In fact I did contact my LABC inspector and he told me that the guidelines had been removed from the 2004 edition because they are covered in the reference to the TRADA (Timber Research And Development Association) tables.

It also appears that the electrician who wired my house didn't bother with the guidelines at all

 

[plugwash]

I wouldn't lose too much sleep over it. Most houses probablly have holes that don't comply with those guidelines and yet we don't seem to have floors failing all over the place.