How to raise bathroom floor level (1st floor bathroom )??

[newbe99]

Does anyone know how to raise floor level in bathroom by 200mm for an area 2m x 1.7m ( the shower tray and bath are to be sited on original floor level so that there is no "step up" to the shower enclousure.

Would the new floor be too heavy on top of the existing floor (it's 1st floor suspended floorboarded floor, supported by joists). The joists have been heavily cut into in the past for the old waste pipes and plumbing .. I'm worried in case they need supporting

many thanks

 

[Cartboy52]

I did this in my old bathroom. There used to be a step down into the bathroom, so I raised the floor and left the bath on the original floor.

The way I did it was to attach some battons to the wall using those bolt things with expanding ends - like you put into a concrete floor. Then, I used joist hangers and put new joists across. New T&G on the new joists and jobs a good'n!

Our original joists looked a bit dodgy as well, so didn't fancy putting the addidional weight on it. The other bonus is you get a good void to put all your pipes through. I have a sink on an internal wall and the waste pipe can run right under the new floor, on top of the old one!

 

[noseall]

as said above. bolt a timber bearer plate to the wall then fill in with joists at say 400 or 450mm centres using jiffy joist hangers.

 

[newbe99]

thanks for advice.. can I check if I need to do this if I just want to raise the floor near where I intend to put a shower tray (say 200mm deep) ie raise floor level by 200mm for a floor area approx 900mm x 1300mm.
there is 1 outside wall, (ie can access brickwork) the other 2 surrounding bathroom are internal non structural breeze block walls (built 1930s)

many thanks in advance for any advice, regards , Gina

 

[Jasonb]

I would just get some 175 or 200mm joists and rest them on the existing floor. Fix with angle brackets if going onto the flooring or skew nail/screw to the joists. Fit noggins to stop the joists twisting. Board the top out with ply then you can tile straight onto it if required

Heres one I prepared earlier

Jason

 

[TicklyT]

Don't forget to allow for access to the bath and shower traps... Sodd's law says they will get blocked if you can't get at them easily

 

[newbe99]

thanks Jason the photos are very enlightening. But yours looks like a concrete floor.. on my 1st floor joists, should I lay the new joists directly on top of the existing floor joists or should they be perpendicular? In collins, they say to build a partition wall off existing floor joists if they are perpendicular, else if running parallel you need to support existing joist.
just wondering if this is similiar

many thanks!

 

[Jasonb]

It was built off a chipboard covered floor.

You can either run the new joists directly above the existing ones if they line up with where you want the new floor or set them at right angles so they span 2-3 joists.

Jason

 

[newbe99]

how did you do yours .. did you run them parallel or perpendicular? is one a structurally better method than the other?

Gina