How many notches allowed in solid joists?

[gwebstech]

Hi

Ive been reading up the guidance on drilling or notching joists, and i can see that for holes it is required distances for holes but i cant see anywhere saying how many notches are allowed in the given spaces

The NICEIC diagram shows limit of notches in a shaded box but surely youre not allowed to notch out all the way from 0.07 to 0.25 span of the joist?

Can anyone clarify?

thanks

 

[EFLImpudence]

https://www.diynot.com/wiki/Electrics:route

 

[gwebstech]

https://www.diynot.com/wiki/Electrics:route

thanks mate, but i cant see anywhere on there where it says what distance to keep between notches

 

[EFLImpudence]

No, I see that now.

Looking elsewhere I find that the maximum length of a notch should be one third of the depth of the joist, but I don't know if that means more than one is allowed.
A lot of conflicting advice.

Someone will know.

 

[gwebstech]

yes its not as clear about notching as it is for drilling holes. Also im not sure if you can notch and drill in the same end? i cant see an answer for that either.

thanks

 

[fluorescence]

surely youre not allowed to notch out all the way from 0.07 to 0.25 span of the joist?

I spent a while researching this very question a while ago and the answer I found was that yes you can notch the whole zone out if you wanted, I am not 100% sure this is true, but the lack of any guidelines for width of each notch and distance between them would suggest to me that it is.

Also if you're going to notch one end of a joist I believe it is recommended to drill any holes at the other end of the joist.

 

[gwebstech]

I spent a while researching this very question a while ago and the answer I found was that yes you can notch the whole zone if you wanted, I am not 100% sure this is ture, but the lack of any guidelines for width of each notch and distance between them would suggest to me that it is.

Also if you're going to notch one end of a joist I believe it is recommended to drill any holes at the other end of the joist.

thanks mate, i was thinking personally, that id check with my BCO and if i can just put several notches in the allowed space, that should be fine anyway as its using the same logic as for holes, and i cant see how the BCO can argue with that but as already said - its a grey area.

 

[Jackrae]

If you have concerns then fit a pair of steel reinforcing plates (bolted through the joist) under the notched area