# Mechanical Code Question of the Day 1 Aug 2018



## jar546 (Aug 1, 2018)

Scenario #1 2015 IMC applies along with all of the 2015 i-Codes:  (this is hypothetical but important)

An existing commercial building is having an AC unit replaced on the roof and the HVAC contractor pulls a permit.  They are swapping out an old unit with a newer, more efficient one.  You notice that the existing location is within 10' of the edge of the roof with no protection as would be required under the code.

Q:  Would you require the installation of guarding per the IMC under the 2015 IMC?

If Yes, Please state why and cite the code section that allows you to do that.

If No, Please state why and cite the code section that allows the contractor to NOT install guarding.

** I am not interested in local opinions but FACTS based on code requirements to make this a learning thread.


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## mtlogcabin (Aug 1, 2018)

Yes we do
2012 IMC
[A] 101.3 Intent.
The purpose of this code is to provide minimum standards to safeguard life or limb, health, property and public welfare by regulating and controlling the design, construction, installation, quality of materials, location, operation and maintenance or use of mechanical systems.

[A] 102.9 Requirements not covered by this code.
Requirements necessary for the strength, stability or proper operation of an existing or proposed mechanical system, or for the public safety, health and general welfare, not specifically covered by this code, shall be determined by the code official.

[A] 104.1 General.
The code official is hereby authorized and directed to enforce the provisions of this code. The code official shall have the authority to render interpretations of this code and to adopt policies and procedures in order to clarify the application of its provisions. Such interpretations, policies and procedures shall be in compliance with the intent and purpose of this code. Such policies and procedures shall not have the effect of waiving requirements specifically provided for in this code.

303.1 General.
Equipment and appliances shall be located as required by this section, specific requirements elsewhere in this code and the conditions of the equipment and appliance listing.

MECHANICAL SYSTEM. A system specifically addressed and regulated in this code and composed of components, devices, appliances and equipment.


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## RJJ (Aug 1, 2018)

The sections are listed above. 101.1,102.9,104.1&303.1. So to answer the question and applying those section the guard would and should be required. There is no reason other than a few dollars to allow an unsafe condition. The same would apply, lets say the wire size was to small or no disconnect. No should allow this to go un corrected either.


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## steveray (Aug 1, 2018)

I think MT nailed it....and to some extent explain the the installation of the equipment (new or replacement) is what drives the guard requirement, so, new equipment, new guard requirement. If someone were replacing a pool previously installed with no barrier, would you require a barrier?


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## Rick18071 (Aug 1, 2018)

What if they have a permit to replace a fan/motor/termination of a commercial kitchen ventilation system on a 20' high sloped roof where there is no means of access or platforms? I don't know if the 2015 would only require a support to tie a life line to but this would cost a lot more than a guard.


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## JBI (Aug 1, 2018)

Different perspective... Starting with the IEBC (it IS an existing building after all),
The Prescriptive Method in Chapter 4 at Section 401.3, Dangerous Conditions. Does provide that the Code Official is authorized to require the elimination of any condition deemed dangerous. Under the Prescriptive Method, YES, you can require the guard.
The Work Area Method would classify this as an Alteration Level 1, and at Chapter 7, Section 702.6. Methods and Materials, the IEBC does reference 'detail of installation...' as needing to comply with current I-Codes. Under the Work Area Method, YES, you can require a guard.
Under the Performance Method there is almost always a way around any specific requirement...


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## mtlogcabin (Aug 1, 2018)

The performance method of the IEBC does not cover the replacement of HVAC equipment, only it's performance for detecting and or moving smoke.
Chapter 3 of the IEBC is where the catch all for using the mechanical code for equipment replacement for existing buildings is required.

301.2 Additional codes.
Alterations, repairs, additions and changes of occupancy to, or relocation of, existing buildings and structures shall comply with the provisions for alterations, repairs, additions and changes of occupancy or relocation, respectively, in this code and the International Energy Conservation Code, International Fire Code, International Fuel Gas Code, International Mechanical Code, International Plumbing Code, International Property Maintenance Code, International Private Sewage Disposal Code, International Residential Code and NFPA 70. Where provisions of the other codes conflict with provisions of this code, the provisions of this code shall take precedence.

The IEBC does not specifically address guards around mechanical equipment or work platforms. This would be required by the mechanical code for existing buildings. Since this same provision is required by the building code we also require the guards to be installed at the time a building is re-roofed


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## RJJ (Aug 1, 2018)

There is a basic concept in enforcement. If you touch it, it must comply. My first approach is this concept. At that point I look for the exception that may give them relief. The HVAC unit and the pool all fall into the same area. I also agree with Mtlogcabin that chapter 3 of the IEBC send you back to the code in charge.


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## Francis Vineyard (Aug 1, 2018)

We'll have to agree to disagree until an official interpretation is rendered or it is specifically spelled out. Can search the internet and find several AHJ do not require guards for replacement of rooftop units.

"Per IMC 2009 304.11 Guards. Guards shall be provided where appliances, equipment, fans or other components that require service and roof hatch openings are located within 10 feet of a roof edge. Since this project is a replacement of existing units, the AHJ most likely not require guards to be installed. However, any worker who services the equipment may have to comply with OSHA requirements. Attachment points for their PPE harnesses may need to be added of suitable points are not available."
Terminal Roof Top HVAC Replacement

* 304.11 Guards. *Guards shall be provided where appliances, equipment, fans or other components that require service and roof hatch openings are located within 6 feet of a roof edge or open side of a walking surface and such edge or open side is located more than 30 inches above the floor, roof or grade below. The guard shall extend not less than 30 inches 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 above the elevated surface adjacent to the guard. The guard shall be constructed so as to prevent the passage of a 21-inch-diameter sphere and shall comply with the loading requirements for guards specified in the International Building Code.
Exception: Guards not required at the time of original installation are not required by this paragraph for equipment repaired or replaced.
2012 NC Mechanical Code
*
Exception: *This section shall not apply to Group R-3 occupancies and dwellings. The replacement of equipment and appliances on existing buildings shall not require the addition of access means that do not already exist the replacement, repair or maintenance of an existing appliance or piece of equipment lawfully in existence at the time of the adoption of this code.
*
Commenters Reason: *No other modification is needed. It becomes cumbersome for a contractor to install additional means of access when all they are doing is providing a replacement of equipment or appliances. The additional expense of adding catwalks, ladders, guardrails, etc can become a financial hardship for the building owner as well. The initial installation may have been in place for 20 years and had been lawful until replacement. Why make a lawful installation unlawful by not allowing the contractor to up-grade the equipment or appliance.
M13-07/08


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## Francis Vineyard (Aug 1, 2018)

*2018 IMC (new)
102.2.1* Where the mechanical system is replaced it shall meet the current code, however the provision for the structure shall comply with the IEBC in accordance with IMC administrative section.

*608.1 General. *Existing mechanical systems undergoing repair shall not make the building less conforming than it was before the repair was undertaken.

*[A] REPAIR.* The  reconstruction or renewal of any part of an existing building for the purpose of its maintenance.


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## Francis Vineyard (Aug 1, 2018)

Here's a dilemma, I saw a code proposal for roof access and guards for the IRC copied from the IMC. Imagine the expense of having to retrofit light frame structures every time a rooftop or wall mount unit needs to be replace.


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## steveray (Aug 1, 2018)

Francis Vineyard said:


> *608.1 General. *Existing mechanical systems undergoing repair shall not make the building less conforming than it was before the repair was undertaken.



So then they just have to prove that the new equipment is not even a fraction of an inch closer to the edge....?


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## Rick18071 (Aug 1, 2018)

I do not know what newer codes say

2009 IMC 102.4 Additions, alterations or repairs.to a mechanical system shall conform to that required for a new mechanical system without requiring the existing mechanical system to comply with all of the requirements of this code,. Additions, alterations or repairs shall not cause an existing mechanical system to become unsafe, hazardous or overloaded.

Argument for not requiring guards if only a mechanical permit is issued and only a mechanical inspector does the inspection:

Is the guard part of the mechanical system? Per definition the guard is part of the system. Will a new roof top unit make it unsafe? It's already unsafe but it won't be more unsafe if no guard is installed. If the newer code requires fire dampers in the ducts where only a new roof top unit is installed I would not make them put fire dampers in. I would not make them upgrade the roof rafters/trusses if they were undersized already for replacing the same size unit . So I would not require a guard.

But if a building permit is issued for a new roof  the guards are required per 2009 IBC 1013.5 and 3405.1.1.


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## Pcinspector1 (Aug 1, 2018)

This explains why the local HVAC contractors don't get permits, the codes requiring something they don't typically do when asked to provide or fabricate guardrails. 

Roof top receptacles? Gas line blocks? Drip legs when there's a possibility of freezing need's to be addressed.

Do you consider roof calc's for additional RTU weight, did you get an engineer involved?


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## RJJ (Aug 1, 2018)

The underlining point here is that a number of sections would support a position to have the guard installed.
Each inspector can chose his/her position. What is behind the original question? First, a roof top change can be much more complicated than it appears. Second, We as inspectors should not leave behind an unsafe condition of any kind. If we do we are just rubber stamping the permit and the process.


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## jar546 (Aug 2, 2018)

**There was a great post here that went way off topic and deserved its own thread.  It was moved here:  https://www.thebuildingcodeforum.com/forum/threads/ieb-code-question-of-the-day-2-aug-2018.23583/

Please continue to keep this thread on topic by hashing this out and enjoy the new thread moved to the IEBC area in the link above.


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