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10' from roof edge

Unfortunately, it seems like one of the requirements of employment to fill the position of Building official is to have your genitailia and spine removed before assuming the position.
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Has anyone thought to see what the code required when the unit was originally installed? The code has not always required the 10' distance. In the 1981 Boca mechanical code the distance was 6' to the roof edge. You don't want to require something that would be considered retro-fitting.
You don't want to require something that would be considered retro-fitting.
Good point but I think requiring the gaurds during a unit replacement can justified through the current code lanquage.

EQUIPMENT, EXISTING. Any equipment regulated by this code which was legally installed prior to the effective date of this code, or for which a permit to install has been issued.

Once the equipment is removed it is no longer existing and the installation of new equipment is required to meet code.

Charging lanquage

301.1 Scope.

This chapter shall govern the approval and installation of all equipment and appliances that comprise parts of the building mechanical systems regulated by this code in accordance with Section 101.2.

Mandatory general requirements as listed in Section 304

304.1 General.

Equipment and appliances shall be installed as required by the terms of their approval, in accordance with the conditions of the listing, the manufacturer’s installation instructions and this code. Manufacturer’s installation instructions shall be available on the job site at the time of inspection.

Specific mandatory requirement

304.10 Guards.

Guards shall be provided where appliances, equipment, fans or other components that require service and roof hatch openings are located within 10 feet (3048 mm) of a roof edge or open side of a walking surface and such edge or open side is located more than 30 inches (762 mm) above the floor, roof or grade below. The guard shall extend not less than 30 inches (762 mm) beyond each end of such appliances, equipment, fans, components and roof hatch openings and the top of the guard shall be located not less than 42 inches (1067 mm) above the elevated surface adjacent to the guard. The guard shall be constructed so as to prevent the passage of a 21-inch-diameter (533 mm) sphere and shall comply with the loading requirements for guards specified in the International Building Code.
I agree mt, we consider replacement = new for HVAC equipment. Service recepts, guards, clearances, the whole enchilada.
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"I agree mt, we consider replacement = new for HVAC equipment. Service recepts, guards,clearances, the whole enchilada".
Does "your whole enchildada" include the structure upon which the
old one was mounted?...Inexact words, ...does the structure qualify
as part of the whole system?....Not just the HVAC equipment itself?

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north star said:
Does "your whole enchildada" include the structure upon which the old one was mounted?...In

exact words, ...does the structure qualify as part of the whole system?....Not just the

HVAC equipment itself?
It should, at a minimum, compare the existing equipment weight to the new equipment weight, and verify that no increase would require structural modifications, IMO.
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If the HVAC equipment mounting structure is part of
the "whole enchilada", then would you still require a
guard if the "new" HVAC equipment is simply switched
out for the old one?.......The "whole enchilada" is
installed closer than 10 ft. to the edge.......This is
the crux of Rick's OP, me thinks.

Your thoughts!

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northstar, as others have answered, yes, if there is a load concern, then yup. As far as a changeout, it is still a new installation, same reason load changes would apply.
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fatboy, ...I agree that it is a "new" [ equipment ] installation !
I even agreed on Topic Response # 3......In trying to think this
through, some might say that because the structural support for
said HVAC equipment has not moved / been altered, that "the
whole enchilada" was not affected ( i.e. - "not new" ), therefore
no guards would be required.........Rick's BO may have even
interpreted it this way.....No additional loading is an assumed
"given constant" in this equation for
discussion purposes.

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Yes, I could see that interp from the loading side. Reallistically, the new equipment most likely weighs less the unit being replaced, and I wouldn't be as concerned, unless I knew that for some reason, the new was upsized. But, replacement still = new for me, so other provisions would apply. JMHO, others obviously may disagree.

I was hoping for my first all-nighter of sleep since rotator cuff surgery last Wednesday........didn't happen......hello middle-of-the-night gremlins! (AKA-Pain!)
I would not enforce the guards for a like for like replacement of an RTU. If I understand you correctly fatboy, if I replaced the old fixtures in a restroom with new fixtures you would consider this a new installation. So if during your inspection you find several accessibility issues you will make them correct these issues. How is this not considered retro-fitting?
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The code sections listed above are [ IMO ] pretty clear regarding "new"

equipment installs.....I too am in the camp of requiring guards on "new"

equipment, regardless of the "like for like" replacement.

To me, if the structural support for said equipment was not installed in

a compliant location, under the code in which it was installed, that does

not negate the current code requirements.....Let's say that the equipment

" Rick 118071 " mentioned was installed under the 2006 codes....Then

by code [ specifically - Section 304.10 ], a guard IS required, ...unless

the powers-that-be overrule it.

Not trying to diss you or start an argument, ...just seems pretty clear,

to me anyway! :cool:

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For those of you who would require guards for a replacement RTU, if it required climbing over a 30" obstacle, would you require compliance? If the existing ladder didn't meet code, do you require a new one to be installed? If it's on a roof with slope greater than 4:12 what do you do?

If it was a replacement attic unit, and the existing access didn't comply, would you make them enlarge it? If the unit was too far away from the access would you require a new access? If existing catwalk didn't comply, would you require replacement? If headroom was less than 30" would you require unit to be moved or roof to be raised?
I consider the guards a life safety issue And a BO could use the building code to require retro work

102.6 Existing structures.

The legal occupancy of any structure existing on the date of adoption of this code shall be permitted to continue without change, except as is specifically covered in this code, the International Property Maintenance Code or the International Fire Code , or as is deemed necessary by the building official for the general safety and welfare of the occupants and the public.

I believe a service tech would be part of the public.
Hi All, new to this Forum!....doing an HVAC replacement on the flat roof of my Townhouse in Santa Monica that was built in 1997. The roof is surrounded by a 2 1/2 foot Parapet wall. The Condenser is closer than 10' to one parapet wall however the wall is not the edge of the building. The exterior wall of the building is 22' away but one story down(another flat roof). If the Condenser fell over the parapet wall, it would land on our flat roof one story below....do you think I would still need a guard rail?
The guard rail is for people, not equipment. Have you read the applicable code sections?
Thanks Bro, if I am reading this thread correctly, it applies to equipment after 2011. Local Building Inspector brought it to my attention....do I have it wrong? Hope so! Code 304.1 Guards referenced above