Offset Link Beams

[Trenno]

Curious as to others' opinion on whether they would go for #1 or #2 for a classic coupled stair/lift core setup that doesn't quite line up (assuming both stair/lift inner dimensions are fixed/minimised to maximise the GIA/£/$).

EDIT - never mind my pros/cons, one of them was a non-issue.

 

[r13]

If the plan layout is up to the liking of the structural engineer, there wouldn't be any offset. Both are not particularly bad, nor good.

 

[jayrod12]

I think number one is the most constructible.

 

[EZBuilding]

With option #2, could you extend the beam further North?

In either case, I believe #2 provides the best option to achieve adequate development of reinforcement. I agree with jayrod that number one is more constructible and is likely also less architecturally sensitive.

 

[jayrod12]

How much of an offset are we talking about here?

Why couldn't they just make the two lift shafts slightly larger to line everything up. If we're talking about a matter of 3-4" which is what it appears on the sketch, even if it's 6", can we not beg the architect to line all those walls up? (I get you are trying to remove that as an option to maximize available space, but some things just make no sense. This is one of those times where I feel it makes no sense to go through all these structural gymnastics.)

 

[KootK]

- #1 will be more economical but really only permits one sided coupling at the offset beam. Only you know if that's sufficient.

- #2 is better from a mechanical perspective as it can accommodate true, two sided coupling, albeit with some degree of weirdness in the middle of the coupling beam where the forces get shifted over.

 

[HTURKAK]

If i were in your shoes, I will try to align the lift wall to staircase wall. Just increasing the lift hole several cm.s to line up should not be a big issue..

 

[hokie66]

#2. I don't see the difficulty of construction, and the wall to wall force transmission is much better.