Handrail to Stud Wall
Handrail to Stud Wall
(OP)
I'm assuming that this has been worked out since it's done all over the place but what is a typical detail for attaching a railing to a stud wall (wood or metal stud). I have not encountered this before as it's usually delegated to others but an architect asked me to look at his detail. From what I see it looks common to specify blocking aligning with the anchor locations. I don't see how the 200# works for this detail, in particular if you apply 200# vertically on the rail, which is about say 3"+ away from the connection. What keeps the blocking from rotating?
The only way that I see this working is to have them lay out and align studs with the anchor locations and then use a tall plate to take the T/C forces from the 200#. Is there a better detail?
The only way that I see this working is to have them lay out and align studs with the anchor locations and then use a tall plate to take the T/C forces from the 200#. Is there a better detail?






RE: Handrail to Stud Wall
If you design the handrail your self then yeah, I would think you want to line it up with a stud. There is a lot of coordination with the framer though unless you make the connector able to slide.
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
To answer your original question, the blocking is usually set to attach between studs as it is rare to get exact alignment for the brackets over a stud. It is also rare that the blocking is able to withstand design loads, but that doesn't stop the field crew from installing anyway!
RE: Handrail to Stud Wall
If the 200# didn't apply vertically then it would be easy, but I've never seen that interpretation - but I haven't looked at many of these. Is this considered a 'guide rail' as you said and is therefore not subject to the same loading requirements?
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
If you're in the US and subject to the IBC (International Building Code) the 200# (applied in any direction) is a code requirement. There's also a requirement for 50# per linear foot, applied in any direction. These loads do not act together. Section 1607 of the IBC has the details.
Regards,
DB
NB: These requirements are in ASCE 7 as well.
RE: Handrail to Stud Wall
The size of the handrail exceeds code maximum by 6 mm. The specified size for the handrail was determined by making it the same size as the guardrail which is at the opposite side of the wall handrail at the same stair case. My calculation indicates the 1.25" diameter STD pipe is not adequate for the guardrail of that height and spacing. The architecture drawings (Addendum) also indicates 1.5" metal pipe for handrail.
It is not a matter of the handrail being under designed; it is more than adequate from a strength and serviceability consideration. The size, moreover, is not too large to prevent an individual from using it for a firm grip.
If necessary, ??? can approach the City of ??? and advise them of the non-conformance and obtain a variance from the code requirement. If this is not forthcoming, it may be necessary to appeal the decision to the ??? Building Commission.
In the event the variance is declined by the ??? Building Commission, it may be necessary to replace the offending handrail.
In the interim, can you determine if the shop drawings were reviewed by either the Engineer of Record, the Architect for the project, or the Contractor? Can you advise me the results of their review.
Dik
RE: Handrail to Stud Wall
Faith is taking the first step even when you can't see the whole staircase. -MLK
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
If you can come up with a plausible and reasonable scenario where the rail would experience a 200# vertical load, please share it with us.
There is a site called juliusblum.com that you may want to look at.
RE: Handrail to Stud Wall
You can't say it's not made for that. If it's there, someone starts falling grabs it and it breaks, someone is getting sued.
RE: Handrail to Stud Wall
I have never tied to justifying the backing for handrails. But, I have been challenged with attaching some handrails to the backing.
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
Is it just me or from a distance, does the figure in the OSHPD seal look like a hand with its fingers crossed?
RE: Handrail to Stud Wall
Wannabe - Thanks for the link, that is along the same lines as other details I've seen. I have not gone through the analysis in detail but eyeballing it I'm surprised if it works for the situation of 200# applied vertically on the rail and the resultant m = 200# x 'e'.... it doesn't seem like the track would have the torsional stiffness or capacity.
RE: Handrail to Stud Wall
http://www.perfectwall.net/metal-framing-info/smoo...
RE: Handrail to Stud Wall
Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.
RE: Handrail to Stud Wall
We see this happen a lot. Architects will often just grab a rail or stair detail from somewhere and use it in their drawings without doing any design checks.
Faith is taking the first step even when you can't see the whole staircase. -MLK
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
RE: Handrail to Stud Wall
I have never tested ANY railing into metal 2x4's.
The "rules" require the 1-1/4 or 1-1/2 nominal dia pipe: They CANNOT be larger nor smaller and still meet the code "grip" requirements. I would like to see your actual calculation where the previous writer said he had to use a thicker pipe for strength purposes. What assumptions have you made?