Floor joist gap from side wall?

[iDIY]

Hi,

Im going to be ordering / fitting 6x2 (2.5m span) floor joists soon. They will be on joist hangars into dense concrete block at each end, 400mm centres.

Im just a bit unsure about the setup along the side walls parallel to the joists. Do they go hard up to the wall or should/must there me a gap?

 

[Deleted member 174758]

You normally leave a small gap, otherwise you can't get a hoist hanger in...

 

[SFK]

No idea what the gap should be, but have found that when length of joist is put very close to wall, over 100 yrs (yes I know) damp from wall has caused damp issues in the joist.
(I guessed trapped damp air).

So when replacing joist (after I improved ventilation) I placed length of joist (about) three inches off the wall. Hopefully big enough space to stop any dead air, big enough room for me to pass my hand and check joist, and small enough so that I cannot stand on this overhang.

 

[Leofric]

50mm gap packed out.

 

[iDIY]

50mm gap packed out.

Thanks, what do you mean by packed out?

 

[Leofric]

Blocks of wood, anybody else care to elaborate feel free. At 2m max centres for restraint straps.

 

[tony1851]

Leave a small gap and you can run cables up and down.

 

[Leofric]

Leave a small gap and you can run cables up and down.

50mm perhaps