Tips for ceiling U-channel needed

[Spelunx]

I am pulling down an old suspended Styrofoam ceiling, and replacing it with a new flash plaster one.

The bit I am a little confused about is attaching the u-channel to the timber joists.

The bloke I bought the plaster off said that it was better to use the channel, as it was easier to get it level.

What is the best way to achieve this? do you use packing for the low bits? or plane out the high bits?

Any tips or tricks would be apreciated, a step by step guide would be even better!

Cheers

Jayson.

[journeyman Mick]

I assume that by "U-Channel" you mean metal ceiling batten. You can get metal clips that nail onto the side of your ceiling joists/truss bottom chords. You just tack them up with one nail through a slotted hole, adjust them up or down and then finish nailing them off. Have a look round the Rondo site.

Mick

[rod@plasterbrok]

Jayson, you use a clip that attaches to the side of the joist. This clip has slots in it so that the first nail can attach the clip in position yet allow it to slide up and down. Then you put another nail in the horizontal slot once the clip is level. For furring channel (top hat section rondo part no 129) use a rondo 226 clip that can be spaced at 1200mm maximum centers. If you are using a nail up batten, ( c section rondo part number 301) then use a rondo part number 304 clip spaced at 900mm maximum centers.

There are several methods to straighten the ceiling using clips. Perhaps the most reliable an quickest method is to use a laser level. However not everyone has a laser level nor knows how to use one effectivley.

So here is the next best method. Straight is usually more important than level, it does not matter so much if a ceiling runs 10mm out of level provided that there is not a door head or the like to show it up over a short span. Therefore if the floor is reasonably level you can measure up the same height in each corner and place a mark. Use a chalk line to flick a visible line between the marks. If you can start so there will be about a 15mm gap between the top on the channel and the bottom of the joist. This will allow for any joist hanging down so you will not have to chop anything out of the joist. (You may want to check that 15mm is enough before you start).

Then put the battens up on each side level with the mark on the wall, make sure each clip is paced on the same side of the joist. Now on every 2nd joist that has a clip you can flick a chalkline level with the top of the clip along the side of the joist. Now all you have to do is nail each clip level with that line and your ceiling will come up dead flat. The intermediate clips between those that you have levelled can be clipped on vitually where the batten sits. They will sag about 1mm over 1200mm or 2-3 mm over 1800mm without a clip so I just fix the clip to the batten and raise it by that amount.

The other method if you are unable to flick a line along the joist is to again get the end battens up and level to the perimeter line then use a string line along the joist where the batten clip will be attached. I normally put the string line above the batten and make sure each batten sit 1mm bellow the line. Or place it under the batten and use a spacer on each end and the same spacer to level the batten to the line.

I hope that is clear enough for you.

BTW I don't find using straight edges for battening very reliable!

Cheers Rod

[Spelunx]

Cheers guys.

The stuff I got sold looks like product number 310. It is listed as 35mm ceiling batten, and is in a U shape.

According to the Rondo website, you can directly screw the batten onto the floor-joists above, or you can use part number 311, which is a direct fixing clip similar to the one you have described, Rod.

Which would be the easier way to go?

Also, Rod, I asked a question here a few months ago about sound-proofing, and you stated that I could use some rubber between the batten and the joists, and this would cut down on some of the vibration coming through from the floor above. How would this work if I went with the direct fix clips?

Cheers

Jayson.

[rod@plasterbrok]

Same sort of product Spelunx, fix the same way as described.

Yes you can fix them direct to the joists, If the joists or trusses are straight enough to start with it is a quick way to batten out. We normally only use clips if there is a need to do so. Usually it is to cover up bolts from steel work or to level a bad frame.

You can use the rubber blocks between the clip and the joist it will still act as a sound barrier. Just use a longer nail to fix the battens. You will need to make the rubber blocks a bit bigger than I would have previously described so both nails will go through the rubber block.

Use a very dense insulation and consider double sheeting or using fire check plasterboard to get better sound proofing.

Cheers Rod

[Spelunx]

Same sort of product Spelunx, fix the same way as described.

Yes you can fix them direct to the joists, If the joists or trusses are straight enough to start with it is a quick way to batten out. We normally only use clips if there is a need to do so. Usually it is to cover up bolts from steel work or to level a bad frame.

You can use the rubber blocks between the clip and the joist it will still act as a sound barrier. Just use a longer nail to fix the battens. You will need to make the rubber blocks a bit bigger than I would have previously described so both nails will go through the rubber block.

Use a very dense insulation and consider double sheeting or using fire check plasterboard to get better sound proofing.

Cheers Rod

Cheers.

The frame looks reasonable, so I think I will screw the channel directly to the jarrah beams.

I have used the old styrene ceiling as insulation by sticking under the floor, then I have got 75mm sound bats to go in, followed by 13mm ceiling plasterboard. I would have liked to have done more, but this seemed like the most cost-effective option, as my budget is tight.

Thanks for the help.

Jayson.