Nails or Screws?

[junglejim]

I’m trying to get advice on fixing counter battens to 18mm osb cassette roof. 
I’ve read some articles suggesting they should be screwed rather than nailed but others saying nails are ok.

 

 Any advice welcome?

 

 Thanks

[SteamyTea]

Nails, screws and bolts all work in a different manner, with screws and bolts being quite different (has (expletive deleted) all to do with the type of tool used to tighten them).

 

What does the panel manufacturer have to say?

[ToughButterCup]

Nails and screws are both fine. I prefer screws because I make mistakes.  And I am not in a rush. The stainless steel screws I use are cheaper than any carpenter.  But still expensive.  

[Iceverge]

Screws for me in this situation. 

 

Nails will have very little pull out resistance from an 18mm layer of OSB. Much less than a solid rafter for instance. 

 

The only exception I might think of is if you were to glue the battens to the OSB before nailing but you probably (hopefully) have a membrane in the way. 

 

 

 

 

[joe90]

If using nails use ring shank.

[SteamyTea]

  On 19/07/2024 at 18:47, joe90 said:

If using nails use ring shank.

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Or those twisted nails.

They are very hard to pull out.

 

Nails work by deforming the timber, which then contracts around the nail shaft.

Screws cut a channel and rely on the cross sectional surface area to stop being pulled out.

Nails, generally, have better shear strength than screws (bolts work differently, they clamp the materials).

[nod]

100% ring nails 

[saveasteading]

I've recently got a nail gun. I will certainly use it for stud. Bang bang bang at varying angles,  roughly in place. But it is too powerful for fixing osb. 

Screws for  greater control. I only buy upmarket ones these days.  They must go in easily and come easily out again.

I've recently tried some with a big receased head on them, and a hex socket. The head means you don't have to hold them, and don't drop them.

They grip the osb nicely.

 

Is that advice? My worry with batten would be splitting. So i think I recommend a self drilling, self clearing, self tapping screw with recessed head and hex connection..

But I haven't ever done battening so I'd welcome others' input.

[LA3222]

They need to be screwed, I have a SIP house and I spoke to technical department at Kingspan Tek - they said screw and directed me to ejot for Screws. Spoke to ejot tech department and they sent me tge pullout tests they'd done fir a couple of screw options...think I went with their stainless steel ones in then end - the screws have to be long enough to for the tip to penetrate at least 20mm beyond the back face of the osb iirc.

[Iceverge]

  On 20/07/2024 at 05:24, LA3222 said:

the screws have to be long enough to for the tip to penetrate at least 20mm beyond the back face of the osb iirc.

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Interesting, what was the logic in going in so far? 

 

I assumes it was a done deal once the main untampered thread of the screw was gone beyond the inner face of the OSB.

[LA3222]

  On 20/07/2024 at 10:24, Iceverge said:

 

Interesting, what was the logic in going in so far? 

 

I assumes it was a done deal once the main untampered thread of the screw was gone beyond the inner face of the OSB.

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Dunno, I didn't ask tbh...they sent me the fixing pullout data sheets which I weren't particularly interested in! Just told what the use was and asked for a recommendation 🤷‍♂️

[saveasteading]

  On 20/07/2024 at 10:24, Iceverge said:

what was the logic in going in so far? 

 

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The first few mm are a point and cutting section,  and sometimes another bit clearing the hole. Then it converts to the thread at full diameter

There will be a minimum number of full threads to cut into the timber and resist pull-out.  I think about 4 or 5 turns typically.

Add these up and 20mm sounds right.

 

3 threads instead of 4 is only going to be a mm or so, but you have lost 25% strength, even though lots of pointy screw is projecting uselessly, it's job being done.

.

[Dave Jones]

galv nails, if you must use screws stainless steel as they will rust.

[jack]

  On 19/07/2024 at 22:39, saveasteading said:

I've recently tried some with a big receased head on them, and a hex socket. The head means you don't have to hold them, and don't drop them.

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For the last couple of years, every time I've finish a box of pozis, I've replaced them with the torx equivalent. They're just so much more pleasant to use.

[junglejim]

Thanks for all the advice… seems like conflicting opinions screws vs nails still. I’m inclined to agree with the arguments for screws but is there any issues with penetrating the insulation?

[joe90]

  On 19/07/2024 at 22:39, saveasteading said:

I've recently got a nail gun.

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Beware, keep your other hand well away from the timber, I have had a 90mm nail hit a knot and exit the timber at 90’ (right through a finger 😣)

[JohnMo]

  On 23/07/2024 at 09:33, joe90 said:

Beware, keep your other hand well away from the timber, I have had a 90mm nail hit a knot and exit the timber at 90’ (right through a finger 😣)

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I did the same, pulling your finger off the nail is the worst bit. Then realising the best thing you have on site is masking tape, to stop the bleeding and a rubber gloves - So you can finish the job without getting blood everywhere.

[saveasteading]

@joe90and @JohnMo

 

Any more advice please? 

 

Do you learn to be more cautious, or useful techniques, or does familiarity cause carelessness?

At present I have used it for about 20 nails and am scared silly of it. I wonder, and worry,  if that is the safest stage?

 

I'm knocking up some stud for site toilets. I'm using screws to create the shape, then banging in lots of nails at angles for rigidity. That way my hand is not tempted to go near the sharp end. Yet.

[joe90]

  On 23/07/2024 at 12:03, saveasteading said:

and am scared silly of it.

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That’s better than being blasé, treat it with respect, same as any power tool.. 

 

  On 23/07/2024 at 10:51, JohnMo said:

pulling your finger off the nail is the worst bit.

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Ha, my young son was with me and he said “you need to go to hospital “ but I replied “they know nothing about nail guns” 🤣 and yes masking tape to stop the flow of blood.

 

the good thing about some paslode nails is the glue on them (looks like red paint) , makes them very difficult to pull out, almost like ring shank nails.

Edited July 23, 2024 by joe90

[JohnMo]

  On 23/07/2024 at 12:03, saveasteading said:

Any more advice please

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Always have masking tape on site, has many unusual uses. Or better still a first aid kit.

[SteamyTea]

  On 23/07/2024 at 15:17, JohnMo said:

better still a first aid kit

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We have a first aid kit at work.

Anyone actually used a triangular bandage?

 

Never got any blue strip plasters in it, lots of square ones, no use at all when you slice the side of your finger and get onion juice in the cut.

Load swearing works better than paracetamol.

[ToughButterCup]

  On 23/07/2024 at 16:23, SteamyTea said:

...

Anyone actually used a triangular bandage?

...

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During First Aid tests every other year, and keeping our grandchildren amused while I'm playing their patient with a broken arm. 

[SteamyTea]

  On 23/07/2024 at 16:45, ToughButterCup said:

 

During First Aid tests every other year, and keeping our grandchildren amused while I'm playing their patient with a broken arm. 

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So not really then.

 

Sticky tape and super glue, and vaseline for burns, all that is needed.

 

Topical subject at work at moment. If someone has a stroke (or suspected stroke) sit them up, it will not make matters worse, and may help.

Get them to hospital ASAP, even if you have to drive them.

 

[markocosic]

Screws for OSB IMO.

 

Nails want 1/3rd and 2/3rd to stand a chance of pulling anything tight..1/3rd through the thing being fixed. 2/3rds into the thing that you're fixing to.

 

You don't have that putting battens onto OSB. They won't be pulled tight to the OSB. They won't offer much uplift resistance.

 

Screws on the other hand don't "waste" energy going through the thing you're attaching (they have a plain "neck" that slides loosely through the hole) and do all their fixing on the threads.

 

Say 5*50 mm with 30 mm of thread and 20 mm of shank (neck) for a 38*19 batten to OSB. Perhaps 5*60 mm if the "drilling" tip is particularly long.

 

Else tack the batten on with nails for speed, then screw through counter battens AND battens AND the OSB with something like 5*80mm screws.

 

C3 rated for corrosion is ok. Stainless screws are not as strong as coated steel screws.