Thread: Joist Hangers and Pryda Brackets

Originally Posted by OBBob

.....................I would be interested to know if builders nails multigrips, triplegrips etc. by hand ... I sort of imagine they wouldn't ... that's a lot of nailing on a whole house?

Generally not, that's a job for the labourer or the apprentice.
Although, yes, I have hand nailed more than a few of them, it really doesn't take that long. Hold nail in position, tap once to start and then reach into your nail bag and grab the next nail while you drive the first home.

Mick

Well ... sounds like I need the practice!!

Actually I don't mind the ones into the top plate but its 5.5m up at my ridge beam that I really don't enjoy ... but should have though of that when I designed it!

Or I need an apprentice / labourer.

OK Guy's ... I have followed the advice and had a very enjoyable weekend fitting 200 multigrips by hand! I guess with modern power and air tools you can get a bit soft. I look at various aspects of my 100 year old house quite often and wonder how they originally built it without all that stuff???

I tell you what though, I'd much rather belt them all in with a hammer than drag an air hose all over a roof frame. If there's something that a hose can get caught on you can be certain it will, and usually when you're up in the roof and on your own.

Nobody mentioned a Pneumatic Palm Nailer yet. I thought this was their main use. (???)

That'd be right! I've never heard of them ... are they any good? How much are they worth?

I thought this was their main use

You're telling the story!

Never seen one in use. Don't know much about them but I gather they just bang in an ordinary nail and are good for spots where it's too tight to swing a hammer or get a nail gun in. Not sure if they would take a flat head clout like you use on these brackets? I reckon I could beat you in a race with you using one of them and me using a hammer

Originally Posted by OBBob

I look at various aspects of my 100 year old house quite often and wonder how they originally built it without all that stuff???

Not to mention no power tools. But more importantly, no silicone, no gappo and no builders bog.

Well maybe the blisters and that black thumbnail were worth it ... the frame inspector counted the nails on few of the pryda brackets!

I am a structural engineer and would approve nailing through the joist hanger provided the right no of nails with the right diameter and right driven depth was achieved, although pryda may advise against it. Very scary to see someone would do without the brackets and skew nail the joist ends (assuming face fixed) into the bearers. Would have something like 5% capacity of the hanger. Seriously dont take this guys advice.
Deanom

i can understand tidy nailing left/right triple grips by hand where they will be seen but for joist hangers and hidden situations the gun is the only way to go! pretty freaky how someone could specify nailing through the holes or not nailing through the holes, buggered if i can see any reason either way..

Yeah, I think you'll find that the inspectors will only approve something if their ass is covered by a document of some sort, which is probably fair enough given the increased litigation levels creeping in.

As for the barckets, they are designed around maximum limit states ... so I image they are tested to where they fail, then a factor of safety is incorporated. So if you were building right on the limit state (neglecting the FS for a minute) then you wouldn't want to be adding holes to the brackets.

I'm guessing a builder who knows his inpectors would have no bracket nailing issues in reality.

I'm pretty sure the nails in bearing on the timber would fail before the steel bracket failed. It wouldn't make sense for Pryda to design their bracket to fail before the timber. Provided the right no of nails are driven sensibly into the bracket, I'm sure it doesnt make much difference whether the nails are driven through the plate or into the holes. Ofcourse you are better off to drive through the holes that have been provided.

Look at it this way: Each hole in one of those brackets is a potential weakness. If the hole is too close to the side of the bracket, it could tear through. So in engineering those brackets, the size, number and location of the holes must be taken into account. Then they would have to be tested, probably to the point of failure, to establish the operational parameters for the design. This would then feed into the load ratings etc which would have to be documented to allow them to be approved for use in construction. Then you want to come along and belt nails into them where ever you feel like?