Installing Joists

[Mark A]

Hi chaps,

When installing new joists how do you deal with warped timbers?

I know the trick when building stud partitions of ensuring all the timbers bend in approximately the same direction, so to the eye any inperfections are not as noticeable, but surely the same technique wouldn't apply to joists as the result would be undulating floors and annoying squeaks?

Any tips would be much appreciated!

Cheers,
Mark

 

[RogerBoyle]

Change them for straight timbers is the best answer
If they are crowned slightly then put the crown up( No different to doing studwalls)
If its a big crown then saw them up for noggins and get better timber
If they snake along the length then add additional noggins

 

[Mark A]

Change them for straight timbers is the best answer
If they are crowned slightly then put the crown up( No different to doing studwalls)
If its a big crown then saw them up for noggins and get better timber
If they snake along the length then add additional noggins

Thanks for your reply.

Maybe warped was too strong a word - let's say slightly un-straight.

I think my problem is that I am trying too hard... I'm sure a chippy would fit them in a day to an acceptable standard, but what is that exactly?

A search online brought up a website referencing the acceptable standards of work for homebuilders, and for joists they stipulate that they should be within 4mm of level per meter, up to a maximum of 24mm over 6m.

Does that sound reasonable? Seems a bit much to me.

Cheers,
Mark

 

[RogerBoyle]

When you have laid your joists out ( Crown up) you can start to level them up a bit more by adding the noggins pushing down on the crown of any that are sticking up more than the rest so the tops and bottoms of the noggins are flush with your joists. If its sticking up by around 6mm or more replace it
This will loose a lot of the unevenness that you may be experiencing and when you have added your finished flooring either boards or sheets ( use 22mm )then you will in all probability find that its all perfectly level. If its still slightly out don't worry about it as a few months down the line it will flatten off .

The inch over the 6 mtr is ok What you don't want is anything more than around 6 mm in any one spot as it may not come back easily