Eaves beam !

[JD7710]

Hello all

Right situation is I'm having a shed built and the fabricator wants to know how I want the eaves beams. I know most buildings have either a timber beam or z purlin type beam, but all the ones I've seen with either of those also have a chs brace between the coloum tops.

I've looked at a building today that has had a length of channel 125x65 fitted between the coloum tops to double as the eaves beam and the brace.

I was gonna go with timber but I now like the look of the channel idea, but is using channel an acceptable practice ?. Or am I better off sticking to either timber or z section ?.

 

[DX 3.90]

I've seen a couple of sheds with channel eaves beams so it's obviously not impossible and would certainly stop them and the rest of the purlins sagging, the only problem would be fixing to it you'd need some good sharp tec screws! You may be better with the C type z purlins as they are better than timber and easier to fix to. But if it doesn't cost much more then do, the shed will look neater in 10yrs time with nice level eaves and probably less issues with gutters holding rubbish in low spots.

 

[Forever Fendt]

the channel eaves beam sounds ok but at 125x65 i hope its not a 20 ft bay have they fixed a timber to the top to fix the roof sheets and the side cladding? strictly speaking the eaves tie should be on the centre line of the stanchion and the rafter

 

[JNP]

Dont let them just use a 125pfc. If they want to use that as the eaves beam then insist on a chs tie on the column centre line too.

We use a [ shaped eaves beam from folded galv, the same as the purlin, then a CHS tie on the column centre line.

 

[JD7710]

Dont let them just use a 125pfc. If they want to use that as the eaves beam then insist on a chs tie on the column centre line too.

We use a [ shaped eaves beam from folded galv, the same as the purlin, then a CHS tie on the column centre line.

I originally spec'd the galv folded eaves beams 190-2.0 at no point did anyone mention putting the chs braces in.
I was hoping by using a 125x65 channel section it would serve as eaves beam and brace but obviously not !.

 

[David.]

A channel section eaves beam with fish plate gussets at either end would be good spec for a farm shed.
Have a Dale building to industrial spec dating to the 80s built just this way, has piece of strip in top of web to pick up hook bolts for sheets. Important thing is to have web stiffeners welded into the top of the stanchions at the rafter connection points.
Cannot see how timber EB on its own is better, under extreme loading the bolts will pull out of the ends of the timbers.

 

[JNP]

The fact that galv eaves beams and purlins were spec'd suggests this is not just a cow shed or machine store but more like a grain store or something similar?, with column loading etc.

 

[JD7710]

The fact that galv eaves beams and purlins were spec'd suggests this is not just a cow shed or machine store but more like a grain store or something similar?, with column loading etc.

No purely machine shed come workshop, columns have 70x10 stiffeners from web - web at the haunch and a morris stiffener I think it called as well. No concrete panels are being fitted and no loading on the columns.

 

[JNP]

In that case a PFC would be ok, but I would expect at least a 150x75 or 180x75. Just out of interest, why no timber eaves?

 

[Bruce Almighty]

On a few 30' bays we have used box section for eaves beam, with fish plate gussets
Can't remember the size, I think 200 x 100 ?

 

[MrA.G.]

A 125 PFC section isn't really an ideal section to be used as a column tie. Column ties are designed to act as axial compression and tension members to resist gable wind loading more so that what the buildings contents will be.

A bigger PFC or CHS section would be better.