Notches in Joists

[withask]

I have had C.H. installed and I think that the joists have been dratically weakened by huge cut-outs. The pipe runs are in the middle of the floor and are about 2" wide and 3" deep. The annoying thing is that plastic pipe was used and holes drilled in the joists to suit. Who could I get to check the structural safety?
Withask

 

[masona]

The pipe runs are in the middle of the floor and are about 2" wide and 3" deep.

What size are the joists?

 

[shaggy]

...and what is the span. (this doesn't sound good )

 

[neilsumner]

If the holes are drilled through the center of the joist then they are in the best place as long as they are not too big in relation to the depth of the joist.
Notching joists from the top is only acceptable if you are at the edge of a joist span.
Notching the top or bottom of a joist in the middle of it's span drastically reduces it's load bearing capacity. IE it's bending strength.


-Neil

 

[DAZB]

This will give you a quick guide to what is generally allowed and it looks like you may need a Structural engineer to check yours now I'm afraid....

http://www.wakefield.gov.uk/Plannin...ontrol/Advice/TimberJoists/TimberJoistsIV.htm

Follow the two links on the right under Timber Joists

 

[kevplumb]

I have had C.H. installed and I think that the joists have been dratically weakened by huge cut-outs. The pipe runs are in the middle of the floor and are about 2" wide and 3" deep. The annoying thing is that plastic pipe was used and holes drilled in the joists to suit. Who could I get to check the structural safety?
Withask

if the holes for the pipes were drilled to suit

why cut a 2""x3"" notch

 

[withask]

Thanks for all replies, the link posted by DAZB was very good.

The joist sizes are 2" X 8" with a 13ft span.

The notches are on the top of the joists and 6ft from the end.

They measure ,on average, two and a half inches wide and two and a half inches deep; some are smaller and some larger.

Only notches have been used and not holes.

I expected to see holes as plastic tubing was used for distribution: which is what I would have used if I had tackled the job myself.

Judging by the comments I need to get some advice. Does anyone have any ideas??? I thought I had picked a well-qualified plumber but obviously dropped a gooly!

Thanks again