Overboard screw length?

[Phoebe]

Just a wonder what folks prefer to use on your average overboard. Just done a small artex ceiling and used 65mm screws and it seemed a bit over the top and obviously more pricey. Cheers for any replies

 

[S a plastering]

No mate thats about right

 

[beddy]

i use 50mm for overboard.

 

[thebigfella]

Yeah 50 is my normal length but I had to go to 60 on the last job as it was a old building, ever job is different you just have to gauge it when you get there

 

[Rhys]

Depends what you're overboarding, some lathe and plaster ceilings can be quite thick. IIRC we use 65mm (though I think the last box we got were 50mm as there was 500 in a box compared to 250 x 65mm for the same price)

 

[Olican]

Usually got plenty of 50mm in the van but I must always cut a little opening to check there are no nasty suprises

 

[bubbles65]

50's are usually enough but as said, it really depends on the depth of the existing ceiling marra :RpS_thumbup:

 

[beddy]

keep plenty in the van. ive got 32s 38s 50s 65s and 100s

 

[DannyMac]

50's or 45's if you're overboarding boards

 

[Arti]

keep plenty in the van. ive got 32s 38s 50s 65s and 100s

Are they not the years of your record collection Beddy.............rock around the clock and all that jazz...........:RpS_thumbup:

 

[Fourplastering]

I use 65's on lath and plaster, some of those bad boys are thick.
50's on board

Basically the screw need to penetrate the timber joist by 25mm

 

[DannyMac]

The depth that the screw needs to penetrate depends entirely on the density of the timber.

 

[smudge505]

into a timber backgrounds screw must penetrate a minimum of 25mm, this is to maintain a secure fix in case of a fire, the density of the timber has nothing to do with it. If you happen to be fixing into a metal substrate then only 10mm of penetration into the substrate is required due to the fact that metal doesnt burn and just warps with the heat of a fire.

 

[carlos]

50mm screws are the norm

 

[DannyMac]

into a timber backgrounds screw must penetrate a minimum of 25mm, this is to maintain a secure fix in case of a fire, the density of the timber has nothing to do with it. If you happen to be fixing into a metal substrate then only 10mm of penetration into the substrate is required due to the fact that metal doesnt burn and just warps with the heat of a fire.

By the time a fire has burnt 20-25 mm into the joists you'd be well fu'cked if you were upstairs anyway. Who thinks this sh1t up?

And besides, for the fire to burn into the joists that much, the plasterboard would already be compromised so what does it matter if it fails since it's not protecting anything anyway.

For what it's worth I was talking in regards to the screws being in far enough to able to take the weight of the board, as per the OPs question, an average overboard.

 

[spunky]

The screws don't take the weight of the board though Danny its the joists

 

[DannyMac]

Yeah that's what I mean't, my point still stands.

 

[spunky]

You don't get minimum fixing for timber densities only length if there's a problem with the timber the screws could slip at any length

 

[DannyMac]

Of course, that goes without saying. If the timber is rotten and soft then you need a longer screw to get into the meat of the wood, this is all common sense.

Alternatively sometimes when the timber is hard as fook, it can be a struggle driving 25mm in.

 

[Rhys]

Of course, that goes without saying. If the timber is rotten and soft then you need a longer screw to get into the meat of the wood, this is all common sense.

Alternatively sometimes when the timber is hard as fook, it can be a struggle driving 25mm in.

Had that on a ceiling at home - utility room one collapsed after a leaking shower. Had to use 75mm screws where wood was soft and 38mm screws were squeaking on other bits (head snapped off one).