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A.D. Miller
12-03-2008, 02:10 PM
I may have asked this question at some time in the past, but don't remember getting a straight answer.

For stair and handrail code compliance issues does anyone have a source for hard rubber, or the like, balls to use for measurement of stair rail openings, etc.? That would require the following precise sizes: 4", 4.375", and 6".

Aaron

John Arnold
12-03-2008, 02:11 PM
I'm not sure, but I suspect JP has balls in that range.

A.D. Miller
12-03-2008, 02:14 PM
I'm not sure, but I suspect JP has balls in that range.

John:

Would that be free range?

Aaron

John Arnold
12-03-2008, 02:59 PM
John:

Would that be free range?

Aaron

Commando?! Surely not.

Jerry Peck
12-03-2008, 03:31 PM
I'm not sure, but I suspect JP has balls in that range.

John,

I do, they are a bit worn for the wear, wrinkly, and such, but, if you'd like a photo ... see attached ... :eek:

Jerry Peck
12-03-2008, 03:40 PM
I may have asked this question at some time in the past, but don't remember getting a straight answer.

For stair and handrail code compliance issues does anyone have a source for hard rubber, or the like, balls to use for measurement of stair rail openings, etc.? That would require the following precise sizes: 4", 4.375", and 6".

Aaron

Aaron,

From Walmart (some) and some craft stores, depends on what they stock.

I have styrene test balls made of polystyrene (I think that is what they are made of) in 2" (for when the bottom rail of a guard rail was 2" maximum above the floor), 4" for the 4" maximum openings, and 6" for the 6" maximum for the triangular area. I have not yet found 4-3/8" test spheres anywhere.

Leave those plastic polystyrene balls in the plastic wrapper, otherwise they will wear down by rubbing up next to things and you will find white powder (not the sniffing kind) laying on the floor of you vehicle, plus, with the plastic wrap left on, you can write on them (which wears off and needs to be re-done occasionally).

A.D. Miller
12-03-2008, 03:47 PM
Aaron,

From Walmart (some) and some craft stores, depends on what they stock.

I have styrene test balls made of polystyrene (I think that is what they are made of) in 2" (for when the bottom rail of a guard rail was 2" maximum above the floor), 4" for the 4" maximum openings, and 6" for the 6" maximum for the triangular area. I have not yet found 4-3/8" test spheres anywhere.

Leave those plastic polystyrene balls in the plastic wrapper, otherwise they will wear down by rubbing up next to things and you will find white powder (not the sniffing kind) laying on the floor of you vehicle, plus, with the plastic wrap left on, you can write on them (which wears off and needs to be re-done occasionally).

JP:

Thanks.

Aaron

Rick Hurst
12-03-2008, 04:35 PM
Aaron,

You can find those at Michaels Craft stores and at the Hobby Lobby.

rick

A.D. Miller
12-04-2008, 06:14 AM
Aaron,

You can find those at Michaels Craft stores and at the Hobby Lobby.

rick

Rick: Thanks. But, if anybody has a scource for balls different than polystyrene, let me know.

Aaron

Jerry Peck
12-04-2008, 08:10 AM
Rick: Thanks. But, if anybody has a scource for balls different than polystyrene, let me know.

Aaron


Let me know too.

I've not yet found a source for wood balls (they would be heavy unless made of balsa wood) or metal balls (even heavier) in the correct sizes.

Thought about turning wood to make balls in those sizes, then realized I'd first need to buy a lathe ... but only after making room for one in my garage ... anyone out there have a lathe and feel like turning some wood down into balls those sizes?

imported_John Smith
12-05-2008, 06:28 AM
ToyShoppe® Jumbo Tennis Ball - $1.99 available at PetSmart

Jerry Peck
12-05-2008, 08:24 AM
The reason that I am still looking for wood (or metal) test spheres is that there are some railings which cannot be properly checked with my polystyrene test spheres, and a balloon or tennis ball would only make those matters worse.

A guard rail is required to resist horizontally applied load of 50 pounds on an area equal to one square foot, including openings and spaces between rails.

Thus, at 50 pounds per square foot, which is 144 square inches, the load applied to a 4" sphere into an opening would be 16 square inches (presuming the opening is not spherical, the opening between two vertical balusters can be presumed to be square as there is only air above and below the test sphere anyway), thus, 144 / 16 = 9, then 50 / 9 = 5.5 pounds horizontal force on that 4" square area being tested.

If I were to apply a horizontal force of 5.5 pounds to the polystyrene sphere, the sphere would crush and pull through, as would a balloon or tennis ball.

This testing becomes especially important with those horizontal wire/rope guard rails we have discussed before.

By the way, if you are trying to look up those forces, they are in the IBC, and 1607.7.1, Exception 1, states that only the loads in 1607.7.7.1.1 are to be applied, which is the 200 pound applied in any direction at any point along the top, and that the top rail, supporting devices, and attachments are to resist that 200 pound load.

Thus, the only the 200 pound top rail load is applicable to one-and-two-family dwellings.

Which means townhouses, etc., should meet the in-fill panel load of 50 pounds per square foot (5.5 pounds applied to the test sphere).

I've seen many guard rails with fancy decorative in-fill components in single family homes which would not meet the in-fill load, but (by code - which is minimum) they do not have to meet it. :confused: I guess it is okay to kill you own kids, and those of guests, but only if you live in a single family home or a duplex????

Brandon Chew
12-06-2008, 12:12 PM
The reason that I am still looking for wood (or metal) test spheres is that there are some railings which cannot be properly checked with my polystyrene test spheres, and a balloon or tennis ball would only make those matters worse.

A guard rail is required to resist horizontally applied load of 50 pounds on an area equal to one square foot, including openings and spaces between rails.

Thus, at 50 pounds per square foot, which is 144 square inches, the load applied to a 4" sphere into an opening would be 16 square inches (presuming the opening is not spherical, the opening between two vertical balusters can be presumed to be square as there is only air above and below the test sphere anyway), thus, 144 / 16 = 9, then 50 / 9 = 5.5 pounds horizontal force on that 4" square area being tested.

If I were to apply a horizontal force of 5.5 pounds to the polystyrene sphere, the sphere would crush and pull through, as would a balloon or tennis ball.

This testing becomes especially important with those horizontal wire/rope guard rails we have discussed before.

By the way, if you are trying to look up those forces, they are in the IBC, and 1607.7.1, Exception 1, states that only the loads in 1607.7.7.1.1 are to be applied, which is the 200 pound applied in any direction at any point along the top, and that the top rail, supporting devices, and attachments are to resist that 200 pound load.

Thus, the only the 200 pound top rail load is applicable to one-and-two-family dwellings.

Which means townhouses, etc., should meet the in-fill panel load of 50 pounds per square foot (5.5 pounds applied to the test sphere).

I've seen many guard rails with fancy decorative in-fill components in single family homes which would not meet the in-fill load, but (by code - which is minimum) they do not have to meet it. :confused: I guess it is okay to kill you own kids, and those of guests, but only if you live in a single family home or a duplex????


All of the code sections that talk about limiting the passage of spheres for various sizes are completely silent about any forces being applied to the sphere. As such, I believe these are intended to be strictly dimensional code requirements.

There are other code sections that talk about load resistance requirements for handrails, guards, and in-fill components. These sections are very specific about the amount of force and the direction in which it is to be applied. Here's the section on in-fill components:



1607.7.1.2 Components. Intermediate rails (all those except the handrail), balusters and panel fillers shall be designed to withstand a horizontally applied normal load of 50 pounds (0.22 kN) on an area equal to 1 square foot (0.093m 2 ), including openings and space between rails. Reactions due to this loading are not required to be superimposed with those of Section 1607.7.1 (http://ecodes.iccsafe.org/iccf/gateway.dll?f=xhitlist$xhitlist_x=Advanced$xhitlis t_vpc=first$xhitlist_xsl=querylink.xsl$xhitlist_se l=title;path;content-type;home-title$xhitlist_d=NYBC2007_free$xhitlist_q=[field folio-destination-name:'NYBC2007_S1607_7_1']$xhitlist_md=target-id=0-0-0-8081)or 1607.7.1.1 (http://ecodes.iccsafe.org/iccf/gateway.dll?f=xhitlist$xhitlist_x=Advanced$xhitlis t_vpc=first$xhitlist_xsl=querylink.xsl$xhitlist_se l=title;path;content-type;home-title$xhitlist_d=NYBC2007_free$xhitlist_q=[field folio-destination-name:'NYBC2007_S1607_7_1_1']$xhitlist_md=target-id=0-0-0-8085).



I don't think using a 4" sphere with 5.5 pounds of force behind it is a valid test procedure. When you try to shove that sphere through a smaller diameter opening, even just fractionally smaller, the force applied to the in-fill components is no longer in a horizontal direction. What you are measuring is the resistance of those components to being spread apart. I don't think there is requirement currently in the code for resistance to that kind of load (and perhaps one is needed?).


IMHO, a proper test procedure for compliance with 1607.7.1.2 (as it is currently written) would need something rigid that was 1 foot square, like a piece of plywood or a metal plate, that had 50 lbs of force behind it in a horizontal direction. It is testing how well the in-fill elements are fastened to the rest of the guard, so they can't break away easily and have someone fall through it. It is not testing how hard or easy it would be for someone to spread apart the in-fill components and climb through (and I'm not aware of a standard currently specified for this kind of test and believe that there should be one).


I imagine the amount of force to be applied in the "passage of a sphere" testing process to be very similar to that which an auto mechanic applies when using a set of feeler gages to measure gap distance on a spark plug.

Dee Stevens
12-06-2008, 02:13 PM
I was just checking the code about the opening limitations on guards, section 1013, specifically 1013.3 which states that "Open guards shall have balusters or ornamental patterns such that a 4-inch-diameter (102 mm) shpere cannot pass through any opening up to a height of 34 inches." That word cannot shows up in all the exceptions as well.

A.D. Miller
12-06-2008, 03:29 PM
I was just checking the code about the opening limitations on guards, section 1013, specifically 1013.3 which states that "Open guards shall have balusters or ornamental patterns such that a 4-inch-diameter (102 mm) shpere cannot pass through any opening up to a height of 34 inches." That word cannot shows up in all the exceptions as well.

Gentlemen:

Looks like Dee may know more about balls than the "pressure Kings".:D

Aaron

Ted Menelly
12-06-2008, 03:50 PM
Gentlemen:

Looks like Dee may know more about balls than the "pressure Kings".:D

Aaron

I do believe that the thread got more response just because of the title.

Jerry Peck
12-06-2008, 08:13 PM
I was just checking the code about the opening limitations on guards, section 1013, specifically 1013.3 which states that "Open guards shall have balusters or ornamental patterns such that a 4-inch-diameter (102 mm) sphere cannot pass through any opening up to a height of 34 inches." That word cannot shows up in all the exceptions as well.

Dee,

And that is why the sphere should be able to withstand the pressure for its proportional area of the 50 pound load, the 5.5 pounds.

I could make the argument that the sphere must withstand the entire 50 pound minimum load requirement (actually, you made that argument for me, the same argument I use when I talk about applying the 50 pound load to the sphere), however, some people balk at it, saying that the load is not applied to the 1 square foot area as the 50 pound load is to be.

By reducing the load down to the area the sphere is interacting with and the load adjusted for that area, they understand the reasoning behind that.

The in-fill components must withstand the 50 pound load applied. The in-fill components must not all that 4" sphere to pass through it. Putting those two together and you get 'the in-fill component must be such that the 4" sphere CANNOT pass through it ... with the 50 pound load applied'.

Here is why: (it is all in the wording the code uses)

1607.7.1.2 Components. Intermediate rails (all those except the handrail), balusters and panel fillers shall be designed to withstand a horizontally applied normal load of 50 pounds (0.22 kN) on an area equal to 1 square foot (0.093m 2 ), including openings and space between rails. Reactions due to this loading are not required to be superimposed with those of Section 1607.7.1 (http://ecodes.iccsafe.org/iccf/gateway.dll?f=xhitlist$xhitlist_x=Advanced$xhitlis t_vpc=first$xhitlist_xsl=querylink.xsl$xhitlist_se l=title;path;content-type;home-title$xhitlist_d=NYBC2007_free$xhitlist_q=[field folio-destination-name:'NYBC2007_S1607_7_1']$xhitlist_md=target-id=0-0-0-8081)or 1607.7.1.1 (http://ecodes.iccsafe.org/iccf/gateway.dll?f=xhitlist$xhitlist_x=Advanced$xhitlis t_vpc=first$xhitlist_xsl=querylink.xsl$xhitlist_se l=title;path;content-type;home-title$xhitlist_d=NYBC2007_free$xhitlist_q=[field folio-destination-name:'NYBC2007_S1607_7_1_1']$xhitlist_md=target-id=0-0-0-8085).

Take a guard rail with vertical balusters, make the vertical balusters 3-7/8" apart, that means that, "including openings and space between rails" (or vertical balusters) the 1 square foot CAN BE 3" wide by 37" high. Okay, so the railing is only 36" high for inside dwelling units, but, for non-dwelling units, that height is 42", so achieving 37" is feasible. Make the railing 42" high, take off for the top rail, the height of the space is now 40", 40" x 3.875" = 155 square inches - *including the openings and space* - so ... (it does not say a 'one foot square area', it specifically states "an area equal to" "one square foot").

I CAN justify applying 50 pounds to that 4" sphere. :)

It is just a lot easier for most people to understand the 5.5 pounds.

And for what I was trying to achieve, the 5.5 pounds would have sufficed. ;)

Richard Pultar
12-06-2008, 10:31 PM
What is the 4.375 size for?

Nolan Kienitz
12-07-2008, 06:59 AM
I do believe that the thread got more response just because of the title.

Aaron's point exactly. Generates a lot of good conversation. ;)

Brandon Chew
12-07-2008, 10:04 AM
I was just checking the code about the opening limitations on guards, section 1013, specifically 1013.3 which states that "Open guards shall have balusters or ornamental patterns such that a 4-inch-diameter (102 mm) shpere cannot pass through any opening up to a height of 34 inches." That word cannot shows up in all the exceptions as well.


The logical fallacy in this argument is that if I choose to use a sphere made of a material that is rigid enough, and and I apply enough force behind it (5 lbs, 50 lbs, 500 lbs, 500 million lbs ... I can keep going as high as I need to), I can make that sphere pass through ANY guard you could conceivably construct out of any material that is not as strong as the sphere.

Why can I do this? Because in every instance where the code specifies "passage of a sphere" it says nothing about what material the sphere should be made of or about the force that should be applied to it, which simply means, I can make the sphere out of anything I want and push on it as hard as I want. And if I can do that, then you cannot build a guard that can keep me from passing a 4 inch sphere through it. I'll make my sphere out of rigid shell filled with depleted uranium and fire it from a howitzer if I need to, and I'll get it to pass through that guard.

Now clearly, testing guards with howitzers is not intended by those sections of the code. I'm taking this argument to the extreme in order to illustrate why putting emphasis on the single word "cannot" does not bring out the true intent of these code sections.

In the real world, these "passage of sphere" requirements have been in the code for a long time, and guards have been constructed, and countless COs have been issued, which in effect are saying that those guards comply with the code.

So what is the intent? I said it before, but it has been overlooked by both your and Jerry's response to my post. The absence of specifying a material for the sphere and the force to be applied to it does not mean that I should determine compliance with those code sections by making the sphere out of anything I want and pushing on it as hard as I want. It means that what I make the sphere out of and how hard I push on it are not factors to be used to determine compliance with those code sections. If they were factors, they would be specified in the code. These code sections (that talk about passage of a sphere) are dimensional (i.e., distance) requirements. There are no "resistance to movement" requirements associated with them.

There are "resistance to movement" requirements for handrails, guards, and in-fill components and they are specified in other sections of code (1607.7.1.2 is one example). Each of these sections is specific about the magnitude of the force to be applied, the area over which it is to be applied, and the direction it is to be applied. None of these code sections say anything about applying a force by using it to push on a sphere of any size.

More on this when I respond to Jerry's post about 5.5 lbs on a 4 inch sphere.

Jerry Peck
12-07-2008, 10:49 AM
So what is the intent?

More on this when I respond to Jerry's post about 5.5 lbs on a 4 inch sphere.

The "intent" of the 4" sphere is NOT ALLOW the passage of a small child's head, not a 4" spherical shell filled with depleted uranium shot from a howitzer.

Thus, back to my 5.5 pounds ... what does the head weigh of a small child? And what likely force would be applied by that head being pushed against a railing?

Thus, using the 5.5 pounds for that force seems to me to be 'on the weak side', so if the guard railing in-fill components cannot resist that force, the guard railing in-fill components will not resist a child slipping their head through.

No howitzer needed. No depleted uranium needed. Just "common sense" is needed.

Fire away!

As I said, I can argue for both the 50 pounds and the 5.5 pounds, with most people accepting the 5.5 pounds logic.

A.D. Miller
12-07-2008, 10:54 AM
The "intent" . . . No howitzer needed. No depleted uranium needed. Just "common sense" is needed. . . .Fire away!

JP: That is you in a nutshell.

Aaron:D

Brandon Chew
12-07-2008, 10:59 AM
Dee,

And that is why the sphere should be able to withstand the pressure for its proportional area of the 50 pound load, the 5.5 pounds.

I could make the argument that the sphere must withstand the entire 50 pound minimum load requirement (actually, you made that argument for me, the same argument I use when I talk about applying the 50 pound load to the sphere), however, some people balk at it, saying that the load is not applied to the 1 square foot area as the 50 pound load is to be.

By reducing the load down to the area the sphere is interacting with and the load adjusted for that area, they understand the reasoning behind that.

The in-fill components must withstand the 50 pound load applied. The in-fill components must not all that 4" sphere to pass through it. Putting those two together and you get 'the in-fill component must be such that the 4" sphere CANNOT pass through it ... with the 50 pound load applied'.

Here is why: (it is all in the wording the code uses)

1607.7.1.2 Components. Intermediate rails (all those except the handrail), balusters and panel fillers shall be designed to withstand a horizontally applied normal load of 50 pounds (0.22 kN) on an area equal to 1 square foot (0.093m 2 ), including openings and space between rails. Reactions due to this loading are not required to be superimposed with those of Section 1607.7.1 (http://ecodes.iccsafe.org/iccf/gateway.dll?f=xhitlist$xhitlist_x=Advanced$xhitlis t_vpc=first$xhitlist_xsl=querylink.xsl$xhitlist_se l=title;path;content-type;home-title$xhitlist_d=NYBC2007_free$xhitlist_q=[field folio-destination-name:'NYBC2007_S1607_7_1']$xhitlist_md=target-id=0-0-0-8081)or 1607.7.1.1 (http://ecodes.iccsafe.org/iccf/gateway.dll?f=xhitlist$xhitlist_x=Advanced$xhitlis t_vpc=first$xhitlist_xsl=querylink.xsl$xhitlist_se l=title;path;content-type;home-title$xhitlist_d=NYBC2007_free$xhitlist_q=[field folio-destination-name:'NYBC2007_S1607_7_1_1']$xhitlist_md=target-id=0-0-0-8085).

Take a guard rail with vertical balusters, make the vertical balusters 3-7/8" apart, that means that, "including openings and space between rails" (or vertical balusters) the 1 square foot CAN BE 3" wide by 37" high. Okay, so the railing is only 36" high for inside dwelling units, but, for non-dwelling units, that height is 42", so achieving 37" is feasible. Make the railing 42" high, take off for the top rail, the height of the space is now 40", 40" x 3.875" = 155 square inches - *including the openings and space* - so ... (it does not say a 'one foot square area', it specifically states "an area equal to" "one square foot").

I CAN justify applying 50 pounds to that 4" sphere. :)

It is just a lot easier for most people to understand the 5.5 pounds.

And for what I was trying to achieve, the 5.5 pounds would have sufficed. ;)


This argument is flawed because you have neglected some very important information in that code section you quoted: "a horizontally applied normal load of 50 pounds" (underline is mine). Once you choose to use a sphere to apply the force to the guard components, you are not applying that force to the components in a horizontal direction -- you are applying it in a radial direction outward from the center of the sphere, distributed along the surface of the sphere that is opposite from where you are putting your 5.5 lb load that is pushing on it.

If you wanted to scale down the 50 lb load to a "footprint" smaller than 1 foot square, and you wanted to apply it to a round object that was 4 inches in diameter, and you wanted that load to be horizontally applied to the guard components, then you should not use a sphere; you should use a rigid 4 inch diameter circular pressure plate. The force to apply to that plate is not 5.5 lbs, it is 4.36 lbs. Here's the math:

Area of circle is pi multiplied by the radius squared. Radius is one half the diameter.

4 inches diameter = 2 inches radius

Area of circle: (3.14) x (2.0) x (2.0) = 12.56 square inches.

Force is 50 lbs applied to an area of 1 foot square, or 144 square inches.

Force per square inch is: (50) / (144) = 0.347 lbs per square inch.

Equivalent force on 4 inch diameter circle is: (12.56) x (0.347) = 4.36 lbs

If you choose a sphere as your test object, you are testing how well the guard infill elements resist being spread apart -- a worthy goal for sure, but there is no standard currently specified in the code for this. Absent this standard, it will be defined by the courts on a case-by-case basis (when an expert convinces a court/jury that the designer was negligent because the guard elements could be "easily" spread apart by a reasonable person).

Jerry Peck
12-07-2008, 11:27 AM
If you wanted to scale down the 50 lb load to a "footprint" smaller than 1 foot square, and you wanted to apply it to a round object that was 4 inches in diameter, and you wanted that load to be horizontally applied to the guard components, then you should not use a sphere; you should use a rigid 4 inch diameter circular pressure plate. The force to apply to that plate is not 5.5 lbs, it is 4.36 lbs. Here's the math:

Area of circle is pi multiplied by the radius squared. Radius is one half the diameter.


Brandon,

That's where your engineering background takes over from your common sense background. ;)

In applying the 5.5 pound calculation to the sphere, I am, as the code said I could, "including the openings and space", which are, naturally, filled with a substance we know of as "air", thus, the part of the sphere which is not bearing on the vertical balusters IS bearing on the "air" in the "openings and space", thus, I can apply a resistance factor of -0- to the air in the "openings or space" (for this argument's purposes, otherwise, yes, scientifically speaking, "air" does offer some resistance, but for this calculation, it is safe to use an air resistance factor of -0- ... for your howitzer example, probably not).

So, whether or not the sphere is actually 16" square inches or 12.56 square inches, the 3.44 square inch difference is being resisted by "air", or, being resisted by 'nothing'.

Thus the head of the small child, NOT being square, is what is being replicated on a general scale as small children's heads are not spherical either, but closer to spherical than to square.

Let's see, we could take a 4" square cube (aren't all cubes square?), fill it with water, dunk a small child's head (4" in dimension) into the water filled cube causing the water which is displaced by the head to be spilled out, remove the small child's head prior to drowning the small child, measure the depth of the water remaining in the cube, then refill the cube, dunking in a 4" sphere, allowing for it's displaced water to be spilled out, remove the sphere, then measure depth of the remaining water. Now compare the water remaining after the 4" sphere and the water remaining after the child's head, that will show "the difference" between a small child's head and a sphere - when each of 4" in dimension. :)

Brandon Chew
12-07-2008, 11:41 AM
The "intent" of the 4" sphere is NOT ALLOW the passage of a small child's head


I'm well aware of that. All "small child's heads" are not a uniform size.


The "intent" of the 4" sphere is NOT ALLOW the passage of a small child's head, not a 4" spherical shell filled with depleted uranium shot from a howitzer.

Thus, back to my 5.5 pounds ... what does the head weigh of a small child? And what likely force would be applied by that head being pushed against a railing?

Thus, using the 5.5 pounds for that force seems to me to be 'on the weak side', so if the guard railing in-fill components cannot resist that force, the guard railing in-fill components will not resist a child slipping their head through.

No howitzer needed. No depleted uranium needed. Just "common sense" is needed.

Fire away!

As I said, I can argue for both the 50 pounds and the 5.5 pounds, with most people accepting the 5.5 pounds logic.


By attempting to ridicule what I've posted, you've overlooked what I've already said about this:


Now clearly, testing guards with howitzers is not intended by those sections of the code. I'm taking this argument to the extreme in order to illustrate why putting emphasis on the single word "cannot" does not bring out the true intent of these code sections.


And it also seems that you've completely missed the point of why I posted that ridiculous example. When determining compliance with the spacing requirements, applied force is not relevant. If it was relevant, it would be specified in the code. Please show where in the ICC codes it says the in-fill components need to resist a force that is trying to spread them apart? It's not in the sections on spacing, and it's not in the sections where design loads on handrails and guards are specified (IBC 1607.7).

Testing how well guard elements resist spreading by trying to push a 4 inch sphere through it with 5.5 pounds of force behind it may very well be a worthy undertaking, but to take it further and suggest that this is testing compliance with a code requirement is making it into something that it is not.

imported_John Smith
12-07-2008, 11:58 AM
TREC doesnt mention a sphere per se, it says 4" diameter. Having said that, couldnt you use anything with a 4" diameter? I know a lot of round things that arent spherical that are referenced in diameter or radius.

"(4) report as in need of repair spacings between intermediate balusters, spindles, or rails for steps, stairways, balconies, and railings that permit passage of an object greater than four inches in diameter;"

Jerry McCarthy
12-07-2008, 12:06 PM
When in the trenches I kept it simple and used my metal clip board that held my field inspection reporting system format that I checked while performing my inspection.
For those that carry a clip board try this; Mark the clip board at spaces of 1-1/2”, 2”, 2-1/2”, 4”, 6”, 7-1/2”, 8”, 9”, 10-1/2” and 12 “. This allows one to check many dimensions as their inspection progresses without having to pull out one’s tape. If you have to ask what those measurements represent you’re not a qualified real estate inspector.

PS: carried a 1-1/4 inch solid steel ball-bearing in my pocket which worked well for checking floor levels. I used to used a pool 8-ball which was rather effective in ending arguments about slope especially when I set them down on a hardwood floor and by gravity they rolled across it until they made that distinctive “clank” sound when they hit the baseboard. I stopped when the agents all began referring to me as that “the hateful 8-ball man.”

Brandon Chew
12-07-2008, 12:50 PM
Brandon,

That's where your engineering background takes over from your common sense background. ;)

In applying the 5.5 pound calculation to the sphere, I am, as the code said I could, "including the openings and space", which are, naturally, filled with a substance we know of as "air", thus, the part of the sphere which is not bearing on the vertical balusters IS bearing on the "air" in the "openings and space", thus, I can apply a resistance factor of -0- to the air in the "openings or space" (for this argument's purposes, otherwise, yes, scientifically speaking, "air" does offer some resistance, but for this calculation, it is safe to use an air resistance factor of -0- ... for your howitzer example, probably not).

So, whether or not the sphere is actually 16" square inches or 12.56 square inches, the 3.44 square inch difference is being resisted by "air", or, being resisted by 'nothing'.

Thus the head of the small child, NOT being square, is what is being replicated on a general scale as small children's heads are not spherical either, but closer to spherical than to square.

Let's see, we could take a 4" square cube (aren't all cubes square?), fill it with water, dunk a small child's head (4" in dimension) into the water filled cube causing the water which is displaced by the head to be spilled out, remove the small child's head prior to drowning the small child, measure the depth of the water remaining in the cube, then refill the cube, dunking in a 4" sphere, allowing for it's displaced water to be spilled out, remove the sphere, then measure depth of the remaining water. Now compare the water remaining after the 4" sphere and the water remaining after the child's head, that will show "the difference" between a small child's head and a sphere - when each of 4" in dimension. :)


I know you mean this tongue-in-cheek ("That's where your engineering background takes over from your common sense background. ;) ") but don't try to dismiss my argument by implying that it lacks common sense. On the contrary. I'm applying a lot of common sense to some straight-forward code sections that most of the country doesn't seem to find too difficult to put into practice every day, while punching holes in some convoluted and flawed logic that is being used to defend someone's interpretation of what they want the code to say. Those challenges have, as yet, gone unanswered.

If you choose a 4 inch sphere as your test object you are no longer applying a load to the guard that is consistent with what is specified in IBC 1606.7 (or any other ICC code section that I am aware of).

The language in the code about "including the openings and space" is there to recognize that all guards are not solid barriers -- that they frequently have openings and spaces -- and to clarify that when the 50 lb force is applied across the one foot square area, some of that area will include "openings and space". It is simply trying to preclude an alternate interpretation where someone might think they mean that you should take the 50 pounds and apply it to 144 square inches of the guard surface (which would be ignoring the openings and space). I think we both agree on this point. I think you "get it" .... and I "get it" too.

Theoretically, you could enlarge or reduce the size of your test plate any amount that you want, and you could make it any shape that you want, as long as that shape will apply a normal force to the guard element in a horizontal direction (your sphere does not do this) and you scale the force up/down to be equal to 50 lb/sq ft or 0.35 lb/ sq in (which is what you are trying to do) over the full test plate area (including the parts of the test plate that would press against "air" or open space).

I don't see where the discussion of cubes and dunking heads in water is relevant to the points I've made which prompted me to jump into this thread, so I'll leave a response to that to others. I'm probably done with this thread unless it can move beyond rehashing previously stated arguments and positions. Gotta move on to a more productive use of my time.

BTW - I agree with other posters that craft stores can be a good source for balls :).

Jerry Peck
12-07-2008, 12:53 PM
I'm well aware of that. All "small child's heads" are not a uniform size.

Well aware of that, however, *by code*, we are limited to those which fit into the 4" sphere size and smaller.


By attempting to ridicule what I've posted, you've overlooked what I've already said about this:

Not ridiculing it, pointing out that over applying the engineer's analytical scientific methods missed the point behind it.


Testing how well guard elements resist spreading by trying to push a 4 inch sphere through it with 5.5 pounds of force behind it may very well be a worthy undertaking,

And, are not codes "minimum" levels of safety?

Thus, using the force requirements of the code, and applying them in a logical manner, does that not test to see if it meets the intended "minimum" levels of safety?

If the in-fill components were to really resist the loads applied to the guard rail, then the in-fill components should be able to resist the same load as as the top rail is required to withstand. After all, when a person falls against the guard rail, them may not hit or grab the top rail, the may hit or grab whatever is closest, which could well be the in-fill components. Under that typical scenario, the 50 pound rated in-fill components of the guard rail could easily just be knocked right out given the 200 pound load falling against it, right?

Without going there (the above), I am simply going with what the code is trying to prevent, a small child from pushing his/her head through the openings.

Let's change the example from vertical balusters to those horizontal wire/ropes types which have horizontal wires/cables/ropes pulled between support columns to serve as the in-fill components of the guard rail.

Those wires/cables/ropes move quite easily, right?

Okay, now take the 4" sphere and begin the test to see if the guard rail in-fill components will resist the passage of that 4" sphere such that the 4" sphere * "CANNOT" * be passed through between the horizontal wires/cables/ropes. In fact, let's go to one which was posted here not long ago using horizontal ropes, ropes which were sagging slightly (as wires/cables/ropes will do).

Now, when testing that style, do you stop when the sphere first hits the higher sagging rope, knowing full well that ANY PRESSURE will allow the sphere to be passed through?

Okay, starting with the last paragraph above - how do you compare that situation to the situation first being discussed, with vertical balusters?

Pressure is pressure is pressure, even though you KNOW the rope is only sagging down under its own weight and there only resistance will be the weight of the rope as it raised to go over the 4" sphere.

Is that horizontal sagging rope in-fill acceptable to you? If not, why not?

Jerry Peck
12-07-2008, 01:00 PM
PS: carried a 1-1/4 inch solid steel ball-bearing in my pocket which worked well for checking floor levels. I used to used a pool 8-ball


I use golf balls, first, they don't break or mar things, plus the little dimples will sound out and reveal loose/unbonded areas of the hardwood floor when the golf ball is rolled along the floor.

I would roll the ball across the floor, if the floor is not level, the ball will turn toward and into the dip, and, after hitting the other side (or even before in some cases) the ball will roll back toward me, showing the low point between me and the opposite wall.

Those little dimples, though, are great for sounding out loose/unbonded areas as the golf ball rolls over them.

A.D. Miller
12-07-2008, 02:57 PM
A better use for all of these balls . . .

YouTube - Music by Balls (http://www.youtube.com/watch?v=SllII1r9VUE)

Aaron

Timothy M. Barr
12-09-2008, 05:25 AM
Why balls Could a round tube work? I turned some round balsa and sliced off sections about one inch thick

A.D. Miller
12-09-2008, 05:55 AM
Why balls Could a round tube work? I turned some round balsa and sliced off sections about one inch thick

Timothy:

I could, except that the code reads:


R312.2 Guard opening limitations. Required guards on open
sides of stairways, raised floor areas, balconies and porches
shall have intermediate rails or ornamental closures which do
not allow passage of a sphere 4 inches (102mm) or more in
diameter.

Exceptions:

1. The triangular openings formed by the riser, tread and
bottom rail of a guard at the open side of a stairway are
permitted to be of such a size that a sphere 6 inches
(152 mm) cannot pass through.
2. Openings for required guards on the sides of stair
treads shall not allow a sphere 4 3/8 inches (107 mm) to
pass through.

and even their diagram (Figure 312.2) indicates the use of spheres. I'd post that, but I have no idea how to do it on the Hann's site. Cut and paste is as old as computers, but won't function in the Hann's realm. Bad foo dogs! Why?

See page 13:
http://www.stairways.org/pdf/2006%20Stair%20IRC%20SCREEN.pdf

Aaron

Jerry Peck
12-09-2008, 07:17 AM
Why balls Could a round tube work? I turned some round balsa and sliced off sections about one inch thick

For quick 'carry-with-me-in-my-clipboard' measurements, I have flat circles cut out of heavy cardboard which are 4", 4-3/8" and 6" is diameter.

But ... when you want to state that it does NOT meet code, you need to use a sphere, because that is what the code states.

Word of caution when using flat circles: you can maneuver and slip flat circles through places that the sphere will not go. If the flat circle does not go, the sphere will not either, however, if the flat circle does go, the sphere *might not*.

Timothy M. Barr
12-09-2008, 09:10 AM
Ill be in my shop this weekend Being I was a toolmaker at one time (22 years)I should be able to turn a sphere. Let me see how long it takes me to turn one Might be able to do you some good

A.D. Miller
12-10-2008, 03:52 AM
Ill be in my shop this weekend Being I was a toolmaker at one time (22 years)I should be able to turn a sphere. Let me see how long it takes me to turn one Might be able to do you some good

I got quotes from some wood turners locally for laminated oak or maple spheres in these sizes and they were stratospheric. I found 4" spheres for a reasonable price, about $15, but the other sizes are not stocked anywhere that I can find. Custom turning is over-the-top expensive.

Aaron

Jerry Peck
12-10-2008, 08:27 AM
I've found a source for 4" and 6" wood balls, but am checking on trying to get the 4-3/8" balls. Maybe I can get them all at one place, maybe even in a set.

I'll let you know when I hear back from them.

Erby Crofutt
12-10-2008, 08:13 PM
That YouTube video HAS to be an animation, doesn't it? Nobody would actually spend all the time it'd take to make that happen in real life.

Wow!

Richard Pultar
12-10-2008, 09:33 PM
no balls required or implied for measuring openings..IF the code development committee wanted a ball they would have said ball.
Regardless of the choice of convention for indexing the number of dimensions of a sphere, the term "sphere" refers to the surface only, so the usual sphere is a two-dimensional surface. The colloquial practice of using the term "sphere" to refer to the interior of a sphere is therefore discouraged, with the interior of the sphere (i.e., the "solid sphere")
being more properly termed a "ball (http://mathworld.wolfram.com/Ball.html)."

A.D. Miller
12-11-2008, 03:30 AM
no balls required or implied for measuring openings..IF the code development committee wanted a ball they would have said ball.
Regardless of the choice of convention for indexing the number of dimensions of a sphere, the term "sphere" refers to the surface only, so the usual sphere is a two-dimensional surface. The colloquial practice of using the term "sphere" to refer to the interior of a sphere is therefore discouraged, with the interior of the sphere (i.e., the "solid sphere")
being more properly termed a "ball (http://mathworld.wolfram.com/Ball.html)."

Wrong. The word is derived from Latin sphaera, from Greek sphaira, literally, ball. It the term can be used to define the two-dimensional surface, but is most commonly used to define a three-dimensional orb.

sphere - Dictionary definition and pronunciation - Yahoo! Education (http://education.yahoo.com/reference/dictionary/entry/sphere)
Sphere - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Sphere)
sphere - Definition from the Merriam-Webster Online Dictionary (http://www.merriam-webster.com/dictionary/sphere)

However, if it pleases you, I will submit that, if you find me a two-dimensional handrail, then I will utilize the two-dimensional sphere you are describing.

We work in the real world, which is three-dimensional. Try thinking that way. It makes things so much easier.

Aaron:D

Jerry Peck
12-11-2008, 07:43 AM
Richard,

A two-dimensional 'sphere' is not a "sphere", that would be a "circle".

To attain the dimensionality of a "sphere", that "circle" would have to be inflated so it was "circular in all dimensions", i.e., "spherical", otherwise known as a "sphere".

spherical - Definition from the Merriam-Webster Online Dictionary (http://www.merriam-webster.com/dictionary/spherical)

Sphere - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Sphere)

Spherical Coordinates -- from Wolfram MathWorld (http://mathworld.wolfram.com/SphericalCoordinates.html)

Spherical Geometry (http://www.math.uncc.edu/~droyster/math3181/notes/hyprgeom/node5.html)

The Geometry of the Sphere (http://math.rice.edu/~pcmi/sphere/)

Richard, you will notice that in each of the above spherical references, they are all beginning with a "sphere", not a "circle".

Jerry Peck
12-11-2008, 07:49 AM
I've found a source for 4" and 6" wood balls, but am checking on trying to get the 4-3/8" balls. Maybe I can get them all at one place, maybe even in a set.

I'll let you know when I hear back from them.

They are getting me a price on two quantities: 5 and 10. Their minimum order quantity is 5, but there should be a price break for a quantity of 10.

When I get the price breakdown, I will let you know. If there are at least 5 interested in getting the 4-3/8" ball, and provided the price is acceptable, are there 5 interested inspectors?

I will ask about a price on a set of: 4", 4-3/8", 6" wood balls.

Jerry Peck
12-11-2008, 10:40 AM
The least expensive place to get 4" and 6" wood balls are:

4" poplar - 4" Wood Ball (http://www.premierwood.com/4-Wood-Ball-P38417.htm)

6" poplar - 6" Wood Ball (http://www.premierwood.com/6-Wood-Ball-P38418.htm)

If you want different wood:

4" and 6" soft maple, poplar, pine, maple, birch, oak - Wood Balls (http://www.exceldowel.com/balls.shtml)

If you want a 4" or 4-3/8" wood ball:

4" maple - Wood Balls (http://www.caseyswood.com/shoppingcart/zen-cart/index.php?main_page=index&cPath=159_157&gclid=CMrpp6uLuZcCFSCysgodKiybSg&sort=20a&page=2)

The last place can get custom turned 4-3/8" wood balls at the not-inexpensive-price of:

hard maple:
minimum order of 3: $44.50 plus shipping
order of 5: $41.50 plus shipping
order of 10: $36.50 plus shipping

soft maple:
minimum order of 3: $36.80 plus shipping
order of 5: $31.80 plus shipping
order of 10: $26.50 plus shipping

The last price for 10 @ $26.50 each is less than a 6" ball of soft maple, poplar, or pine from one source and only slightly more than a 6" ball of poplar from another source, so the price is not expensive in that respect.

What do you guys say?

How many are interested?

A.D. Miller
12-11-2008, 11:01 AM
JP:

I'll take two of each for a total of 6.

Aaron

Rick Hurst
12-11-2008, 11:09 AM
Aaron,

Have you checked out that store over there in Mesquite near the Home Depot on LBJ. Its a woodworking store that may possibly have these wooden balls or could get them. Sorry, don't know the name of the place but it would be easy to find. Call me if you need to.

rick

A.D. Miller
12-11-2008, 11:14 AM
Aaron,

Have you checked out that store over there in Mesquite near the Home Depot on LBJ. Its a woodworking store that may possibly have these wooden balls or could get them. Sorry, don't know the name of the place but it would be easy to find. Call me if you need to.

rick

Rick:

I contacted several local places. 4" is standard and usually in stock. 6" is standard and usually not in stock. 4.375" is not standard and prociey to turn unless in large quantities. Looks like JP has found a reasonbly priced source.

Aaron

Rick Hurst
12-11-2008, 11:14 AM
Aaron,

Just thought of the name.

Its called Rockler's Woodworking and Craft store.

rick

Jerry Peck
12-11-2008, 11:17 AM
I contacted several local places. 4" is standard and usually in stock. 6" is standard and usually not in stock.

Aaron,

What prices are their 4" and 6" wood balls and how do they compare to the ones on the links I posted?

The main odd one is the 4-3/8" ball, that will have to be custom turned.

Rick Hurst
12-11-2008, 11:19 AM
Your probably right. I just went to their web site and they don't show 4 in. balls. Probably could order them if needed though.

And to think, I'm just been using a tape measure all these years. Guess I need to get some sphere's myself.

rick

Jerry Peck
12-11-2008, 11:20 AM
Another use for that 6" ball (the foam ones I have are too light for this use) is to roll across floors for checking levelness.

The larger and heavier ball will roll over surfaces the small golf balls get caught in ... of course, though, those dimples in the golf balls do sound out loose/unbonded wood floor areas.

Rick Hurst
12-11-2008, 11:24 AM
Jerry,

Seems you to be the winner of the bigger balls.

This place does not have the larger balls in stock.
Hardwood Balls - Rockler Woodworking Tools (http://www.rockler.com/product.cfm?page=5371&filter=wood%20balls)


I guess we'll need to order them from the JP Bigger Ball Emporium.:D

rick

A.D. Miller
12-11-2008, 03:16 PM
Aaron,

What prices are their 4" and 6" wood balls and how do they compare to the ones on the links I posted?

The main odd one is the 4-3/8" ball, that will have to be custom turned.

JP:

Your price is the best. Hard maple would be better I think. Let me know how you want to proceed.

Aaron

Richard Pultar
12-11-2008, 04:56 PM
of course a 21 inch sphere for a guard in group I 3, F, H and S is a BALL if they want a ball they would say BALL . just going by the IRC
you are kidding right ?? about using a ball I hope.. 2 dimensional and all that

Jerry Peck
12-11-2008, 06:11 PM
you are kidding right ?? about using a ball I hope.. 2 dimensional and all that.

Richard,

What's "2 dimensional and all that" stuff? :confused:

You are kidding, right?

Every guardrail and stairway I've ever inspected (other than those done for plan review) have been three dimensional in nature.

The code calls for the use of a three dimensional object: a sphere.

What do you use? Anything 'other than' a sphere (a ball) is not inspecting as to whether or not it meets code - but, if you are a minimalist home inspector only looking to make sure the address is correct, sure, I guess there would be no need for one. :rolleyes:

Jerry Peck
12-11-2008, 06:14 PM
Question for those who know: How soft is "soft maple"? Does it dent easily?

Harder or softer than SYP pine?

Harder or softer than spruce/pine/fir?

I would want one that did not dent or gouge easily.

Oak would be nice, but it would (I am sure) cost much more.

Billy Stephens
12-11-2008, 07:57 PM
Question for those who know: How soft is "soft maple"? Does it dent easily?

.
.
Janka hardness (http://www.sizes.com/units/janka.htm)
.

Ted Menelly
12-12-2008, 06:40 AM
Me thinks that if a poll were taken you would find that most (vast majority) home inspectors don't use balls to inspect the stair openings. 99% of the time a simple tape measure is going to do the same job. I am not inclined to call them minimalist inspectors.

Just my opinion. I do have a couple of flat round plastic but in most cases they don't get used. If a stair is in question first off I will take more time and measure, gage different openings.

Good conversation though.

Jerry Peck
12-12-2008, 10:23 AM
Janka hardness (http://www.sizes.com/units/janka.htm).

Anybody know where we can get some ipe WOOD balls? :D

Jerry Peck
12-12-2008, 10:27 AM
I am not inclined to call them minimalist inspectors.

Ted,

My minimalist comment was directed toward TM and RP as they seem to be in competition with each other as to who can do the least and call the worst stuff as being good.

Rick Hurst
12-12-2008, 10:42 AM
.

Anybody know where we can get some ipe balls? :D


Here you go Jerry. :p How they play them in those games I'll never know. Ipe is the wood used in the making of cricket balls is it not?