Can't decide....
I'm going to raise the underarm on my w trusses, due to circumstances it's much easier to overlap it against the upper arms at the eaves.
For example, the top frame is 50 mm and the bottom frame 45... (I could glue a 4mm plywood on the side)
BUT!
Will it be a much weaker solution than with nail plates?
I have a longer common/ possible nailing area with overlap since the underarm is angled out to zero.
On the other hand, I get the loads in a straight line with a nail plate...
I also remember that "imported byggaren" doesn't recommend nail plates except in factory construction
Please help!!!
I'm going to raise the underarm on my w trusses, due to circumstances it's much easier to overlap it against the upper arms at the eaves.
For example, the top frame is 50 mm and the bottom frame 45... (I could glue a 4mm plywood on the side)
BUT!
Will it be a much weaker solution than with nail plates?
I have a longer common/ possible nailing area with overlap since the underarm is angled out to zero.
On the other hand, I get the loads in a straight line with a nail plate...
I also remember that "imported byggaren" doesn't recommend nail plates except in factory construction
Please help!!!
Last edited:
The underram and överram do you mean? 
I think it should be fine, if you want to be really sure you can put an underram on each side. That way you can attach the actual framework relatively securely too.
But I think you should talk to a konstruktör.
I think it should be fine, if you want to be really sure you can put an underram on each side. That way you can attach the actual framework relatively securely too.
But I think you should talk to a konstruktör.
Jo menar ju de
Yes, it should hold, and that's what my carpenter thinks as well.
But I would like to have some margin.
Nobody manufactures a new truss like that anymore and there are no calculations for overlapping layouts..
On the other hand, there was no bottom frame at all in these two trusses that are to be redone,,, the top frames were supported from an old truss about a meter-- which in turn was only standing on one! outer wall and in the middle of a non-load-bearing interior wall :eek:
It would be interesting to find out how much difference there is in the strength of the different seams...
Yes, it should hold, and that's what my carpenter thinks as well.
But I would like to have some margin.
Nobody manufactures a new truss like that anymore and there are no calculations for overlapping layouts..
On the other hand, there was no bottom frame at all in these two trusses that are to be redone,,, the top frames were supported from an old truss about a meter-- which in turn was only standing on one! outer wall and in the middle of a non-load-bearing interior wall :eek:
It would be interesting to find out how much difference there is in the strength of the different seams...
Nail plates (plates with punched and then unfolded elongated teeth) are used in factory-made trusses and are pressed into the wood with special pressing tools.
Nailing plates (plates with punched holes for manual nailing) are used in on-site built joints.
Lapping (lap joints with wood or K-plywood) is used in on-site built joints.
The strongest in relation to size are factory nail plates. Which of the others is strongest depends on design, number of nails, distribution, types of loads applied, load direction, etc. That nailing plates are mainly used is because lapping is usually in the way when insulating the roof beams.
/Ingenjören
Nailing plates (plates with punched holes for manual nailing) are used in on-site built joints.
Lapping (lap joints with wood or K-plywood) is used in on-site built joints.
The strongest in relation to size are factory nail plates. Which of the others is strongest depends on design, number of nails, distribution, types of loads applied, load direction, etc. That nailing plates are mainly used is because lapping is usually in the way when insulating the roof beams.
/Ingenjören
I'm not sure if I understood what you want to do ...
So you have W-trusses today!?
You want to nail a new lower chord (is it called lower chord in trusses? or just in frame trusses, I wonder) that is higher up in the truss?
And then remove the old lower chord? Get higher ceiling height?
I also believe that the builder meant the nail plates that factories press on with hydraulic presses, which are not suitable/possible to use on construction sites.
So you have W-trusses today!?
You want to nail a new lower chord (is it called lower chord in trusses? or just in frame trusses, I wonder
) that is higher up in the truss?And then remove the old lower chord? Get higher ceiling height?
I also believe that the builder meant the nail plates that factories press on with hydraulic presses, which are not suitable/possible to use on construction sites.
http://www.byggahus.se/newreply.php?do=newreply&p=442019
Well... according to the link above (if I did it correctly), he meant nail "nings" plates, as did I.
By overlapping I mean that the upper frame goes down beside (overlapping) the lower frame and is screwed together with it (not through), thus a single-shear joint.
That is, without splices.
Could place the equivalent of the upper frame's thickness in between and splice on the other side.
But it's precisely the lateral load that remains uncertain. Especially on the braces...
Well... according to the link above (if I did it correctly), he meant nail "nings" plates, as did I.
By overlapping I mean that the upper frame goes down beside (overlapping) the lower frame and is screwed together with it (not through), thus a single-shear joint.
That is, without splices.
Could place the equivalent of the upper frame's thickness in between and splice on the other side.
But it's precisely the lateral load that remains uncertain. Especially on the braces...