Oversized notches, contractor offered to brace/bridge

[StretfordReno]

Plumber has notched across all the joists far beyond the 35mm allowable by building regs.

As a fix — after raising concerns — the contractors are offering to brace/bridge the joists.

My concern is that will do little to address the problem as it’s adding strength in the wrong direction and it seems like sistering should be the option.

Do I need to get a SE out and get them to tell the contractor how to remedy the issue (the contractor will claim the notches are old despite the room never having had a radiator and the property being on storage heating)? Should the contractor get out a SE out? Do I need to involve building regs?

The project is already two weeks over and we have had plenty to complain about — with them also butchering our floorboards and putting the notches in such a position there is nothing to mail the floorboards back into.

Ultimately, while we know they have done a bad job — our main concern is making sure the floor doesn’t fall in and we don’t let our desperation to get the job finished override our safety concerns. We’re currently living out of storage and sofa surfing because the properly is in no fit state to move into (of which the floors is just one issue).

Advice and guidance — particularly on how worried to be is much appreciated.

 

[Dereekoo]

What size and span and spacing are the joist, how deep are the notches and where are they in position to the span

 

[StretfordReno]

What size and span and spacing are the joist, how deep are the notches and where are they in position to the span

The bedroom is 4m long in the length the joists run — the joists are 2 x 8, they are about 4 and a half floorboards away from the wall (around 25 - 30 inches) and they are about 20 inches between each joist. I’m not in the house so these are best guesses at the moment.

 

[StretfordReno]

The notches are around 4.5 - 5cms at their deepest

 

[thomp1983]

Notching Joists Will Thye Need Sistering?

Hi all, Sometime prior to buying our house someone has butchered in some 22mm rad pipes that have always squeaked and rubbed on the floorboards. I'll be laying new flooring next week so today I'm on sorting out the pipework. The original notches in the joists were just enough to stuff 2...

www.diynot.com

Look at my similar thread and how I fixed it. Do as I did and it should be fine.

 

[Dereekoo]

The bedroom is 4m long in the length the joists run — the joists are 2 x 8, they are about 4 and a half floorboards away from the wall (around 25 - 30 inches) and they are about 20 inches between each joist. I’m not in the house so these are best guesses at the moment.

Well taking off 50mm and taking the joists as c16 2 x 6 spaced at 500 , running the calcs, the max deflection is shown to be 14.5mm against an allowable of 12mm and structural max bending moment is 1.1kNm against allowable of 1.2kNm so structurally it is sound although deflection is outside prescribed limits. C24 timber would bring deflection to 12mm and an allowable bending moment of 1.7knm

Using 2 x 8 deflection is 6mm and allowable bending moment 2 kNm

So in essence its not going to collapse and taking into account that its deflections at the centre of the joist will be somewhere between 14.5 and 6mm (more towards 6 than 14.5 but indeterminable by calculation) its not something to get to worried about but having said that for piece of mind perhaps you may wish to do something as thomp1983 did , since the strengthening isn't where its really needed (in the compression zone in the top of the joist where the notch is) its not a structurally calculable/efficient bodge but more a suck it and see solution but it won't do any harm. Or you could possibly go with https://www.screwfix.com/p/simpson-...LqjHxLCLroCK0e2LdjdOJc-q4vgA61_0aApm4EALw_wcB