notching joists

[joe-90]

This is something I've been wondering about for a while.

I recently read a book by a BCO about building regs.

In it he said that the maximum joist notch was one eighth of the depth of the joist concerned. In the standard 150mm joist this is 18.75mm.

This means that 22mm pipe is a complete no-no as just the pipe alone would break the rules.

I work under floorboards quite a lot installing security systems and I've seen notches as deep as 75mm!

How do plumbers get around this - or do they just ignore the regs?

One other point; taking into account the above, is there any way (legal or otherwise) to get bath and sink wastes across the joist run?


cheers.
joe

 

[Paul Barker]

You are correct the people who have done that were not properly trained.

You can drill joists to 1/4 of their depth in the middle with one diameter between two drilled holes.
Where distancees for waste pipe are great there is no option but a pump or a raised plinth.

There are also rules about positions along the joists which are ignored by the poorly trained too.

I did a central heating estimate for a person I new from other things (radio ham). Any way I din't ge the job, but because the brand new boiler wouldn't fire up my friend asked me in to have a look. I was scared to walk across the floor. They had notched the joists the full length of the living room right in the centre of the span with a hugely oversized furrow seemed about 4 inches wide and 3 inches deep. The firm was corgi registered.

The commissioning fault was incorrect polarity.

I told him the regs over joists and left it with him. You get what you pay for.

 

[nstreet]

See page 13 on this publication for joist notching specification: http://www.nhbcbuilder.co.uk/NHBCpublications/LiteratureLibrary/Technical/filedownload,21418,en.pdf

 

[joe-90]

You are correct the people who have done that were not properly trained.

You can drill joists to 1/4 of their depth in the middle with one diameter between two drilled holes.
Where distancees for waste pipe are great there is no option but a pump or a raised plinth.

There are also rules about positions along the joists which are ignored by the poorly trained too.

Yes he said that too but I've never seen anyone out there taking the sligthtest notice of it. They simply saw the joist with a skillsaw and hit the notch out with a hammer. I guess plastic pipe might make them observe the regs a bit more.


lee

++++++++++++++++++++++++

See page 13 on this publication for joist notching specification: http://www.nhbcbuilder.co.uk/NHBCpu...y/Technical/filedownload,21418,en.pdf[/QUOTE]



That's a handy publication.


lee

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joe 90

please note 10a, forum rules

 

[PEDANTICVINDICTIVEMAN]

Stop worrying get the old circular saw out and notch away wherever you like, nobody is watching.

 

[Nige F]

Well said PVM.......I had a job once.where the house-1920`s had been lit by gas lamps The notches were unbelievable.I showed the owner, removed the old iron pipes and used most of the notches for my overpriced lash up No bowing of ceilings etc. so go ahead

 

[PEDANTICVINDICTIVEMAN]

Yea it's only modern crap houses which are built with sapling branches right on the limit which cause notching problems, NHBC my arse

 

[Paul Barker]

I wouldn't buy a house under a hundred and twenty years old. The real quality ones of that era made in Scarborough for rich West Yorkshire industrialists weekend use are made to a standard long forgotten which will live on another 120 years beyond the battery hen living quaters they build for folk today to live in who have no posessions, and probably no interests except TV staelite tv playstations and tinternet on a neat laptop that gets put away in cupboard under stairs next to shoe rack hung on wall.

 

[Softus]

Hear hear PB