what is a hanging beam

[dazzadazza]

hello,

i have an old workers cottage west of melbourne. i just got half my attic converted to storage space and want to do the other half myself by laying some flooring. i was warned i need to replace my hanging beams which are skew-whiff. what exactly are they? i know it's a silly question but i have no idea and haven't found a basic definition of 'hanging beam' or how they work anywhere???

cheers,

dazza

[ozwinner]

A hanging beam runs at 90 to the ceiling joists and the joists "hang" off it via joist hangers which are nothing more that pressed meta.

Al

[echnidna]

Its a beam that runs across the ceiling joists in the middle of the room.
The joists are bracketed or cleated to the beam. So the joist loads hang from that beam.

You might also need to fit separate floor joists to hold the weight of the floor as the ceiling joists are normally only sized to hold ceiling loads.

[ozwinner]

A hanging beam runs at 90 to the ceiling joists and the joists "hang" off it via joist hangers which are nothing more that pressed metal.

Al

[dazzadazza]

thanks very much.

i just found this diagram on the web which made sense: http://www.mii.com/artefact/download.asp?aid=26774

now, tell me, what is it that keeps the hanging beam in place - is it held there because it is attached to all the joists? or is it bolted at the ends?

[Metung]

This pic may also be helpful.

[Pulse]

The joists hang from the hanging beam, not the other way around. If you are adding storage to the attic then you may need to upsize the hanging beam or add extra hanging beams to take the load. The ceiling may need temporary propping if you ar removing a hanging beam.


Cheers
Pulse

[Metung]

Are the ceiling joists and ceiling battens one and the same thing in this scenario or would you fix battens to the joists?

[echnidna]

Generally ceiling lining (plaster) is fixed directly to the ceiling joists.
on rare occaisions battens are fixed to the celing joists.

Generally (dontcha love that word) battens are fixed to the bottom chords of roof trusses to support the plaster but on rare occaisions extra roof trusses are used at a spacing of 600mm so the plaster can be fixed to the bottom chords without battens.

[les88]

thanks very much.

i just found this diagram on the web which made sense: http://www.mii.com/artefact/download.asp?aid=26774

now, tell me, what is it that keeps the hanging beam in place - is it held there because it is attached to all the joists? or is it bolted at the ends?

The hanging beam is supported each end on the wall. I would install a spacer [ a couple of bits of fibro] under the ends to stop the beam pushing on the joists.In the early days the type of fasteners shown here had not been invented we used ceiling dogs. A ceiling dog was made out of 1/4 inch steel about 6 inches long and bent at 90 degrees each end and sharpened to a sharp point the bent pieces were at right angles to each other. All the timbers were installed with the bow up, and they varied a bit. As you could not put any weight on the joists at this stage of construction, you would sit on the hanger and lift the joist to the hanger scue nail it then drive the dog in. If the room had a big span you could have more than one hanging beam. The ceilings were fixed on battens because the underneath of the joists were not straight enough.

[Metung]

To change the subject slightly, I had an interesting experience after installing my steel/tin inverted "U" shaped ceiling battens. I was sweeping up on a couple of occasions after installation and I noticed these little round steel discs. On the second occasion I did a bit more investigation and found they were the head of the screws that I had used to fix the ceiling battens and had sheared off. I certainly hadn't over-tensioned them and I reckon they had gone overboard when the "X" was stamped in the head of the screw and therby weakened it. I re-fixed the faulty ones and hope now that the plaster doesn't come crashing down one day.