Nail plates and square twist nails.

[Watshot]

Hi, my engineer has specified galvanised nail plates (76x203) either side of 50x100 studs, to connect to rafters in a loft conversion.

Question is, with one on either side of a 50mm timber, standard 30mm square twist nails are going to be in conflict where they meet in the middle. Should I be using a different nail (are there shorter square twist nails?), and do you nail every hole in the plate?

Many thanks.

 

[tony1851]

Typical SE; gives you a spec, but fails to tell you how to do it.

My first question would be why the nail plates in the first place?
In securing these, even assuming you could get them and the nails in, you would be shaking the tiles loose.
Are the studs structural (ie supporting the roof, or perhaps the floor suspended off them)?
Seems an odd arrangement.

 

[Watshot]

Yes, they are supporting the roof in place of the purlins and bearers, with additional collars at the new ceiling height. So one under each rafter down onto the new steel top plate. This then forms the usual stud wall sides to the room.

I can get them in okay, apart from the doubled up rafters where the roof windows are (guess I could sandwich a plate in first), just wondering about all the nails meeting in the middle!

 

[Watshot]

Here's the specific detail. You can see the nail plate where it joins the rafter at the top of the drawing.

Untitled

• Watshot
• 25 Sep 2010
• 2

 

[tony1851]

Can you put the one on the opposite side diagonally? That way there shouldn't be too much problem with the nails hitting each other.

 

[Watshot]

I guess offsetting them slightly would work. I thought this would be a fairly typical set up with a lot of rafters (especially older) being 47-50mm. Just wondered what the normal practise was.

I'll assume like similar metalwork to nail every available hole.

What about rafter doubling? I'm re-roofing and doing all the windows first before fitting these studs, should I sandwich a plate in between ready for the stud later? Or double up the stud?

Thanks.