Mechanical Mezzanine Live Load 1

[BSVBD]

What Live Load do you use for a Mechanical Mezzanine?

From a 1991 code I've used 75 PSF.

Lately I've considered Walkways and elevated platforms at 60 PSF and then opted for the greater 75 PSF.

When in doubt - 125 PSF.

I realize i need to consider the equipment weight(s).

I'm looking for a documented Live Load pressure, more applicable and specific to the actual occupancy than what IBC Table 1607.1 offers.

Thank you!

 

[JStructsteel]

I dont think ASCE has a designation for that. I would use a light mfg of 125psf, or get some idea on the equipment up there. If there is room, it will more than likely also be used for storage too.

 

[msquared48]

ASCE 7-05 Section 4.5 would govern - Loads Not Specified.

Coordinate and agree with the local jurisdiction on a design load.

I have used 75 psf in the past, but 125 may be more reasonable.

Create a load takeoff using the anticipated machinery weights and use it to justify your load used to the jurisdiction.

If you do not know the weights, be VERY conservative.

Mike McCann, PE, SE (WA)

 

[MacGruber22]

Recently, I had a mech mezzanine in two different parts of a building. Boiler-related equipment on one and air conditioning units on the other. Guess which one was 200 psf and the other 60 psf. I beat on my mechanical engineers to provide me with "real" loads and then adjust for future equipment based on their recommendations.

"It is imperative Cunth doesn't get his hands on those codes."

 

[dik]

If considering equipment loading separately, then a companion live load of 75psf is not uncommon.

 

[wannabeSE]

The closest reference that I know is the DoD's UFC 3-301-01 (

http://www.wbdg.org/ffc/dod/unified-facilities-criteria-ufc/ufc-3-301-01).

It has the following:
Mechanical equipment room (general) 100 psf
Mechanical room (HVAC) 125 psf
Mechanical telephone and radio equipment room 150 psf

 

[Leftwow]

We use 75 psf for industrial standard access platforms and 100 psf for industrial operating platforms. We also put "collateral" loads on the platform, being a 1 kip point load anywhere on the platform, as per PIP.

 

[stevenspm]

What I have been using lately comes out of the ASCE 7-10 commentary for live loads, where they have a table of additional live loads, table C4-1 on page 344. From that table I have started using Air Conditioning (machine space) load of 200psf for unknown mechanical platforms.