IIRC when they were destructive testing guards at VT they used 600 lbs as the factor of safety. The Simpson tie down solution was the only survivor and it wasn't pretty. I believe they harnessed a football player to a spring scale and failed to generate over about 80 lbs of pull. There is an article from JLC on the testing. If the inspector wanted to apply 200 lbs I believe I have to allow that. I try to build stout but I seriously doubt many would survive and I suspect most connection areas would be beyond allowables. I'm not clear on where the requirement came from?
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destructive testing
- Thread starter tbz
- Start date
The IBC does not contemplate tests other than those specifically required. It is not the building inspector’s job to perform tests rather the inspector can ask the design professional for evidence of compliance. Testing may not be the best way to resolve the issue.
I would suggest that the jurisdiction does not want the inspectors performing tests because of liability concerns. In addition the inspector can typically better spend the time performing other inspections.
This question suggests that somebody has too much free time or has a distorted perception of what the building code requires.
My position is that the building inspector can only ask for testing when he has reason to believe that there is a problem. You could possibly modify your building code to require more testing but I would suggest that there would be great resistance.
The way you typically show compliance to Section 1607.7.1 is by performing calculations to show that the forces can be resisted. Usually it is obvious that only the local members need to be checked but theoretically it is open ended how far you must track the loads.
I would suggest that the jurisdiction does not want the inspectors performing tests because of liability concerns. In addition the inspector can typically better spend the time performing other inspections.
This question suggests that somebody has too much free time or has a distorted perception of what the building code requires.
My position is that the building inspector can only ask for testing when he has reason to believe that there is a problem. You could possibly modify your building code to require more testing but I would suggest that there would be great resistance.
The way you typically show compliance to Section 1607.7.1 is by performing calculations to show that the forces can be resisted. Usually it is obvious that only the local members need to be checked but theoretically it is open ended how far you must track the loads.
As the inspector you should be checking to see that the work is done in accordance with the approved plans and in a professional manner; giving a tug on a guard rail should do the latter and observation should do the former. Getting into testing is, as pointed out up the thread, an invitation to get into problems.
permitguy
REGISTERED
There is also a question as to how much deflection constitutes a failure.
I would agree, but I wouldn't consider giving the guard a shove to be a test, either.
khsmith55
Bronze Member
Agree with RGLA with caveats. First ask for design calculations from the Architect/Engineer, confirm the railing was built according to the construction documents then ask the DPR to field test ( I believe that would be within the scope of AIA B141), if they decline, do the test your self. On a side note, I use a large game scale to test railings for compliance and a digital fish scale to test opening force for accessible doors.
tbz
SAWHORSE
KHSMITH55,
you noted you use a large game scale, what do you use as your pass fail point? and if fail am I correct in my assumption that you require the permit holder to provide an engineers review and or test before passing it?
DRP,
The VT testing from all the documentation I read was done on the posts, this is another point that few seem to remember the loads are on the whole guard as a system, there are published papers with peer review that show by adding connections and additional turns, the guard system strength is increased and if the test were done on full guards rather than just posts by it's self, I would venture a guess that the results would be different based on the configuration of how the guards were built, and the promoted product would not be required.
you noted you use a large game scale, what do you use as your pass fail point? and if fail am I correct in my assumption that you require the permit holder to provide an engineers review and or test before passing it?
DRP,
The VT testing from all the documentation I read was done on the posts, this is another point that few seem to remember the loads are on the whole guard as a system, there are published papers with peer review that show by adding connections and additional turns, the guard system strength is increased and if the test were done on full guards rather than just posts by it's self, I would venture a guess that the results would be different based on the configuration of how the guards were built, and the promoted product would not be required.
tbz
SAWHORSE
DRP,
We have done some testing on all wood frames mounted to wood construction, but the infill has either been metal inlay or cable infill.
Frame work to accept cable infill is the best comparison to just testing a post, it has been over a year since I read through the VT study, but the study from what I remember reading never really tested complete deck and guard assemblies, just the post connection, thus not allowing for other factors.
I would have loved to have seen them do complete common built deck designs and not just the post free standing.
As for 50' straight runs of wood guard being built,that is very uncommon in my region of the country from what I have seen. But if built under the IRC, would really not change much since the IRC is limited to just the 200 lb point load and not the 50lb P/LFT. If built under the IBC, there would be a lot of bracing up or connections like the study shows as a good construction method.
We do work on a fair amount of wood deck structures and our mountings are not much different with the forces applied, however our structured metal product does have a large advantage over all wood construction for a guard with spreading the forces applied.
Tom
We have done some testing on all wood frames mounted to wood construction, but the infill has either been metal inlay or cable infill.
Frame work to accept cable infill is the best comparison to just testing a post, it has been over a year since I read through the VT study, but the study from what I remember reading never really tested complete deck and guard assemblies, just the post connection, thus not allowing for other factors.
I would have loved to have seen them do complete common built deck designs and not just the post free standing.
As for 50' straight runs of wood guard being built,that is very uncommon in my region of the country from what I have seen. But if built under the IRC, would really not change much since the IRC is limited to just the 200 lb point load and not the 50lb P/LFT. If built under the IBC, there would be a lot of bracing up or connections like the study shows as a good construction method.
We do work on a fair amount of wood deck structures and our mountings are not much different with the forces applied, however our structured metal product does have a large advantage over all wood construction for a guard with spreading the forces applied.
Tom
jj1289
SAWHORSE
Lets bring this subject back up on destructive testing. Would you make the same stance for firestopping and fireproof patching? Special inspections for firestopping only kick in once certain thresholds are met or the BO requires an SI for firestopping. My question comes down to smaller projects and you need to verify the system was installed per the listing?
Nothing in the code prevents a building official from doing destructive testing if necessary to verify compliance. It is expected by the code writers and firestop experts that random destructive testing is the only way to verify compliance on firestopping systems other than physically watching the system be installed.
[A] 104.11.2 Tests. Whenever there is insufficient
evidence of compliance with the provisions of this code,
or evidence that a material or method does not conform to
the requirements of this code, or in order to substantiate
claims for alternative materials or methods, the building
official shall have the authority to require tests as evidence
of compliance to be made without expense to the jurisdiction.
Test methods shall be as specified in this code or by
other recognized test standards. In the absence of recognized
and accepted test methods, the building official shall
approve the testing procedures. Tests shall be performed
by an approved agency. Reports of such tests shall be
retained by the building official for the period required for
retention of public records.
evidence of compliance with the provisions of this code,
or evidence that a material or method does not conform to
the requirements of this code, or in order to substantiate
claims for alternative materials or methods, the building
official shall have the authority to require tests as evidence
of compliance to be made without expense to the jurisdiction.
Test methods shall be as specified in this code or by
other recognized test standards. In the absence of recognized
and accepted test methods, the building official shall
approve the testing procedures. Tests shall be performed
by an approved agency. Reports of such tests shall be
retained by the building official for the period required for
retention of public records.
Yankee Chronicler
REGISTERED
Please delete. Old thread
steveray
SAWHORSE
While I have not done it, I would fully support and suggest it...As I know how often it is wrong...I require FS SI on all multi story wood project through IBC 1705.1.1
tmurray
SAWHORSE
Yup. I've had people disassemble a firestopping system to verify compliance.
I typically tell them ahead of time that I'm going to pick a few to look at. Even though you're not telling them which ones your going to have them rip apart, it seems to help notifying them ahead of time that you will be.
I typically tell them ahead of time that I'm going to pick a few to look at. Even though you're not telling them which ones your going to have them rip apart, it seems to help notifying them ahead of time that you will be.
Yankee Chronicler
REGISTERED
The discussion. I posted before noticing that the original discussion (and the particular post to which I replied) is fourteen years old. There was no way for me to remove my post entirely, so I changed it to a request that jar remove it.
tbz
SAWHORSE
1st off, don't every delete any old threads,
just move the new current input to a new thread.
just move the new current input to a new thread.
Yankee Chronicler
REGISTERED
I was just trying to be funny. I'm a "class clown" by nature, but due to the limited nature of text only conversation, often my attempts at humor fall flat.
Inspector Gadget
REGISTERED
On large builds, I often put notes in the plans review document that destructive testing may take place.
Oddly enough, the one place I had fully planned on doing destructive testing was a large government building.... except I showed up for a spot inspection the day the firestop installer was present, and the guy was so giddy that a building official was (a) onsite (b) inspecting fire stops and (c) knew what systems were that the blighter geeked out, showed me some systems he had just created and generally demonstrated such passion and competence that I never actually did any destructive testing.