Soil pipe through joists - HELP!!!

[thenezza]

I’m in the process of refitting my bathroom and upon lifting the floor have discovered that one of the previous occupants has cut massive notches out of the joists for pretty much the entire length of the room. There is less than an inch left of the joists in places… as you can see from the picture the cuts are also right next to the supporting wall. The joists run into the bedroom to the left where they finally meet the supporting wall. What can I do to re-enforce the joists? Will I have to get a steal installed under them?
Thanks in advance,
Lee

Untitled

• thenezza
• 7 May 2013
• 1

 

[Jackrae]

What is normally fitted to the floor above the joists. If you don't want to fit a lintel under the joists (in the room below + plus support pillars) you could tie the cut ends of the joists together with steel bridging fabrications above the notches. However I'd surmise you'd be talking about at least 2" square box section to do this, which means the floor above the bridge pieces would be about 2" to 3" higher than the rest of the floor. The bridge pieces would require 2 sets of drilled lugs (say 1.5" x 3/16") welded on and hanging down each side of each joist end (a total of 8 lugs). Adjacent lugs would require to be about 8" apart to give sufficient rigidity, and the bolt holes should penetrate the joist in their centres (4" down for an 8" joist) In effect this would mean each bridge piece would be around 28" long.

 

[rjm2k]

Could you reposition the loo to remove the need for the soil pipe there and then repair the joists? Not sure if something like this is what you need to repair http://www.wickes.co.uk/invt/152829/?source=123_75 but they are none structural so I suspect you need more.

Assuming the chipboard was screwed into the joists, whilst it is up the whole lot will be weaker so I'd be careful what's in the next room!

 

[phatboy]

I would not walk anywhere near it, and get a structural engineers advice ASAP.

Its a wonder that the floor hasn't fallen through already. This is potentially very dangerous!

This is no DIY task to repair.

 

[TheVictorian]

Personally I'd have the soil pipe boxed in against the wall above the joists then repair the joists with 6x2 coach bolted through both sides probably to 2 foot each side.

However, I'm no structural engineer so this is just a personal opinion...

 

[rjm2k]

Might be wise to put some acros and a scaffold board under it temporarily, but be careful not to put too much pressure on it so as not to disturb it. I'm no SE though.

 

[thenezza]

I can re-run the soil pipe so it takes a right turn and follows the joists along then out of the property, I think it may have been like this for 10+ years! I have screwed the boards back down for now..
What does anyone think about two other lengths of timber bolted through both sides of the existing joist?

 

[ivixor]

What is directly underneath the cut? It looks like a plasterboard ceiling is to the right, but perhaps the joists are actually resting on a wall of some kind?

If so, it would explain why it hasn't fallen down yet!

 

[TheVictorian]

To me it looks like the cuts are about 6 inches to the left of a wall below.

 

[thenezza]

Its just the lath and plaster ceiling of our dining room, the plasterboard is our kitchen ceiling. The wall that supports the jouists is visible just to the right of the soil pipe.

 

[ivixor]

Its just the lath and plaster ceiling of our dining room, the plasterboard is our kitchen ceiling. The wall that supports the jouists is visible just to the right of the soil pipe.

Ok, that's quite alarming then! Personally I'd prop it up from underneath sharpish then get a proper builder in to repair those joists. Given what might happen if you do it wrong, don't think it's worth attempting a repair if you are not 100% confident.

 

[hazetimesfive]

quite impressive that is, the notching seems cleanly done.. most odd.

 

[phatboy]

What happened in the end then? Has it all been fixed now, and if so how?

 

[Porque223]

First, measure the no-load deflection by putting a straightedge across the joist top right over the pipe cutout. This will be a triangle, with the straightedge being the top, long side of the triangle.

You can measure the change in deflection by using your own body weight. It's a concentrated load at distance X from one of the supports.
If there are joist supports just to the left of the wall in the photo you may not have much at all.

Having measurements will make everyone pay attention.

It does look bad, though.

 

[sooey]

Are you taking the pizz?
You're asking him to put his weight on that to measure the feckin deflection?
He's lucky if he's got an inch of joist left there. How the hell that's stayed up is anyones guess.