How much joist can be cut out fo CH pipes

[AnthonyRad]

Hi all,

Heating engineer has curved 15mm ch pipes where the wall meets the ceiling instead of notching the joist further and putting them at a 90 degree angle so completely hidden when ceiling is boarded and wall bonded then plastered. He explained that he couldn't notch out the joist anymore and the joist was so tight to the wall he had to do it like that.

Had the plasterer round and he will have to build out the wall 40mm, 'double dot and dab' to ensure the curved section of pipes won't be visible. That is a whole lot of extra time and expense and wasted space to build out a whole length of wall 40mm just to hide 2 small sections of pipes especially when I want to be hanging heavy things on the wall in future. (also don't like coving so can't do that to hide them)

Is it reasonable to ask him to notch out more of the joist (size 7x2), even chase out more of the brick behind if needed to put them in at a 90 degree angle. I could even put metal bat straps across the notch also for belts and braces?

Thanks

(the electric cabling resting on the pipes will be clipped up don't worry)

 

[SimonG]

Board out above, drill out the wall down back of joists and away you go. Just been lazy.

 

[ShaunCorbs]

Your not supposed to notch the bottom out but 1/8th the depth of the joist so about 3/4 of an inch max

 

[exedon2]

If you asked a building inspector how much you can notch underside of joist the answer would be none! Building regs very clearly lay out where you can notch or drill joists.
As has been said lazy job floor boards up neat notch chase behind joist job done everyday stuff.

 

[Scott_D]

Change it to soldered elbows tight to the bottom of the joist.
Cross batten the joist and board over, lowering the ceiling by 20mm ?

 

[townfanjon]

Our job is absolutely impossible to do without notching or holeing joists .
To cut 15 mm off the bottom of that joist is more than ok in my book ,
I am pretty sure the house wont fall down .

 

[AnthonyRad]

If you asked a building inspector how much you can notch underside of joist the answer would be none! Building regs very clearly lay out where you can notch or drill joists.
As has been said lazy job floor boards up neat notch chase behind joist job done everyday stuff.

Thanks, if I get him to do as you described will that be ok as there will then be a notch at the top directly above the small notch at the bottom he's already done?

 

[Ben-gee]

Plate the side with 18mm ply once it’s done.

 

[exedon2]

Spot on ply plate screwed and bonded with one of expanding floor glues (caberfloor or similar) will make best of a bad job.

 

[Keefy]

Off the top of my head it's 1/8th the depth of the joist and ideally no closer than 25% of the span away from the wall. Not always possible I know but yes, straps/plates are a wise idea.