help me decide stud and osb spec.

[saveasteading]

I'm going to knock up a temporary toilet block in an outbuilding. There are already a pair of wc s with no enclosure, connecting to a 'country' septic tank , but they are scabby so I will use  new wc s.

It will be the site toilets and then eventually become one garage and one garden facility.

 

Stud and osb walls, no need for ceilings, but maybe a couple of joists to stop it rattling. 2 salvaged doors. No fancy inner decoration at this stage.

 

Stud in 38 x 63 seems flimsy so perhaps go for 38 x 89.   £50 more.  Am I being conservative here?

OSB in 18mm or 11mm.   I'm thinking 11mm is enough.   £110 difference.

perhaps the thinner osb should be screwed on rather than use a nail gun.

 

I have to set an example in economy here, plus I actually want to keep the costs down, but a wobbly old thing will do the opposite.

 

 

 

 

[Russell griffiths]

The thing with 68mm studwork that I don’t think people think about is running services 

putting a cable through the centre of a stud puts it only 30mm from the surface, which as far as I’m aware isn’t deep enough to keep it the recommended 50mm in to give it half a chance of not being screwed through. 
 

im aware it should be in a safe zone, but good practice and all that stuff. 
68 for wardrobe walls and anything non important 

89 for dividing walls. 

[Mr Punter]

38 x 89 @ 600 ctrs and 9mm OSB is fine.  Nail the OSB @ 300 ctrs.  Use treated timber if you want it to last.

[saveasteading]

1 minute ago, Mr Punter said:

9mm OSB is fine

That's another £36 the right way. It just seems awfully skinny.

6 minutes ago, Russell griffiths said:

running services 

just some dangly wires and pipes at this stage. we can add a service void next year...or whenever.

89mm seems sensible though as it is sort of semi outdoors. (old ugly barn with 2 walls.)  And thinking about it:  I expect I will end up flooring over it for storage of my precious stuff that might come in handy but  I have to keep out of sight....or throw.

 

So the current status is 89mm stud @ 600cc, a few joists, 9mm osb but perhaps (?) screwed rather than nailed......£340 plus vat, before the toilets etc.

 

I have to decide whether I need a sole plate and fabricate panels on the ground, or literally stick build it.

The latter saves 20m of stud, and keeps all the work light for weak old me, but involves some ups and downs for fixing the header.

The former is probably technically easier and faster , but will need a hand to heave up to place.

 

For those interested, these quotes are from Travis P. I use Wickes less 10% less VAT as the easy test and we are well below that, and free delivery.

For screws etc, TP are exactly the same prices as Toolstation, which they own.

[saveasteading]

1. Scope for improvement. 2. detailed design. Actually we will carry on right across to where the trailer is. as a cubby hole.

 

 

[SimonD]

1 hour ago, saveasteading said:

1. Scope for improvement. 2. detailed design. Actually we will carry on right across to where the trailer is. as a cubby hole.

 

 

 

I'd go 38 x 89 at 600c/c and use 11mm OSB with a sole plate especially if you carry across. Change door no. 1 to inward opening so there is no risk of someone going into or coming out of to other loo getting smacked by outward opening door. Question for the BH masses - do any toilet doors open outwards?

[Mr Punter]

13 minutes ago, SimonD said:

Question for the BH masses - do any toilet doors open outwards?

 

Yes if it is a new build and on the entrance floor building regs require it. Part M

Edited June 4 by Mr Punter

[AppleDown]

25 minutes ago, Mr Punter said:

 

Yes if it is a new build and on the entrance floor building regs require it. Part M

If you have more than one loo downstairs - maybe a cloakroom and a bathroom - only one needs to open outwards. Plus there are minium distances needed between toilet and walls/doors for wheelchair users.