Roof Trusses higher on one side by 20mm (not level)

[connick159]

Hi, I've just come to boarding internal walls on a bathroom and can see that the roof truss (ceiling plasterboard will be fixed to the truss) is some 20mm higher on one side of the room than the other (across about 2.8m.)

 

The walls that meet the ceiling will be tiled so the difference will stick out like dogs balls, A couple of questions:

 

1. Whats the best way to fix the difference? Shimming or sistering the underside of the trusses or something else? (builder long gone so up to me to sort it out)

2. Is such a difference an acceptable amount? (whats a general tolerance over about 3m  - I'd have thought the trusses should be dead level?)

 

Thanks in advance.

Edited October 26, 2022 by connick159

[Canski]

Maybe stitch some 3x2 to the chords but level them up and board up to those ? 

[Gus Potter]

1 hour ago, connick159 said:

Is such a difference an acceptable amount?

No but you have  you have what you have.

 

Do you know why this is the case? Try and figure out just for your own piece of mind if this is an indicator of a bigger problem. Maybe post some more info if you are worried.

1 hour ago, Canski said:

Maybe stitch some 3x2 to the chords but level them up and board up to those ? 

If you can set you mind at ease then this is a good way to go. Don't forget the noggings / dwangs!

 

On something like this you would be looking at (from memory) a level tolerance of 10mm when it was built . But it depends on age as timber creeps over time so it's not an exact science.

[nod]

8 hours ago, connick159 said:

Hi, I've just come to boarding internal walls on a bathroom and can see that the roof truss (ceiling plasterboard will be fixed to the truss) is some 20mm higher on one side of the room than the other (across about 2.8m.)

 

The walls that meet the ceiling will be tiled so the difference will stick out like dogs balls, A couple of questions:

 

1. Whats the best way to fix the difference? Shimming or sistering the underside of the trusses or something else? (builder long gone so up to me to sort it out)

2. Is such a difference an acceptable amount? (whats a general tolerance over about 3m  - I'd have thought the trusses should be dead level?)

 

Thanks in advance.

I never board directly on to trusses 

There’s always some undulating Hangers Bad alignment etc 

Fix 5x1 to the highest side and simply level and pack down where needed 

About thirty quid and an hours work on a bathroom 

[Dave Jones]

no issue with boarding to trusses its what 99.99% of every build does. 

 

Odd that you have a 20mm drop, assuming the wall plates are level to each other then it could be the crap quality of timber. Sistering is absolutely fine. Ask the truss company to supply the timber free if the issue isnt caused by your walls.

[joe90]

Ordinarily I don’t think you would notice, but tiles!!!!, yes, like @nod says batten it out, (it’s his day job so he should know).

[connick159]

12 hours ago, nod said:

I never board directly on to trusses 

There’s always some undulating Hangers Bad alignment etc 

Fix 5x1 to the highest side and simply level and pack down where needed 

About thirty quid and an hours work on a bathroom 

thanks but sorry, i'm a bit lost. Do you mean getting 5 x 1 battens and screwing them up directly to the underside of the trusses and using packer to get it level? or screw them onto the side of the truss and drop the batten at the high side so it hangs down lower than truss and gets it all  level?

thanks again.

[nod]

7 minutes ago, connick159 said:

thanks but sorry, i'm a bit lost. Do you mean getting 5 x 1 battens and screwing them up directly to the underside of the trusses and using packer to get it level? or screw them onto the side of the truss and drop the batten at the high side so it hangs down lower than truss and gets it all  level?

thanks again.

Directly under 

As pictured on our previous build 

[nod]

7 minutes ago, connick159 said:

thanks but sorry, i'm a bit lost. Do you mean getting 5 x 1 battens and screwing them up directly to the underside of the trusses and using packer to get it level? or screw them onto the side of the truss and drop the batten at the high side so it hangs down lower than truss and gets it all  level?

thanks again.

Directly under 

As pictured on our previous build 

[Temp]

23 hours ago, connick159 said:

 

1. Whats the best way to fix the difference? Shimming or sistering the underside of the trusses or something else?

 

Sistering to the side of the truss is probably easiest. No need to cut tapers.

[markocosic]

You don't cut tapers; you pack them where they need to be fatter @Temp

[Dave Jones]

14 hours ago, nod said:

Directly under 

As pictured on our previous build 

 

use pozi's next time for service access and dont have to bother with double battening palaver

 

[nod]

22 minutes ago, markocosic said:

You don't cut tapers; you pack them where they need to be fatter @Temp

Exactly 

Quite common on most builds