Mezzanine supported modular office with a two-wall modular building below
Whether you’re running out of room on the plant floor or need to oversee production, mezzanines are commonly employed to support and elevate modular buildings. Recently we received some great photos back on a project we completed last month for a mezzanine supported modular office that I thought you might like to see. The customer was located right here in Northeast Ohio. They were putting in a new line on the plant floor and needed to tear down some offices they had in order to make room. There wasn’t enough space to relocate the offices elsewhere on the plant floor, so they decided to utilize some of their unused overhead space.
A 9’ high mezzanine supported modular office with an 8’ high modular wall system below.
When thinking on putting in a mezzanine supported modular building, it’s important to consider just how much space is available. Remember that with typical column spans in low seismic areas, you’ll probably lose 1’3” to 1’5” for the mezzanine itself. If you plan on having people move through the area you will need to maintain a minimum of 7’ for clearance. The modular building panels are typically 8’ or 9’ tall, and unless you are planning on supporting them by the structure above, you will probably want about a foot more in order to install the roof deck to the panels which helps form the membrane that holds the system together. In this particular case the customer’s mezzanine had a clearance height of 8’7” with a 9’10” top of deck. This provided us enough room to install a modular office above (9’ tall panels, 9’3-1/8” overall height, 8’6” clearance height) and an 8’ high (8’3-1/8” overall with a 7’6” clear ceiling height) modular wall system below.
Four wall modular office above the mezzanine with customer provided/ installed floor covering
While designing these mezzanine supported modular offices, we’re often asked if we can utilize the adjacent existing walls. While this is commonly done on the main floor of a facility, unfortunately we cannot do this up on top of the mezzanine deck. There will always be some movement and vibrations on top of an elevated structure and because of this the structure would need to be a four wall system and not tie into the adjacent walls. In this particular care, we put in a four wall system above the mezzanine deck as well as a two wall system below the deck to create an enclosed pass way between the production floor, the front offices beyond the cinder block wall, and the production floor entrance way to the outside.
Two wall modular wall system below the mezzanine
It took our installers 6 work days to unload and install (both mechanical and electrical) the 24’x10’ mezzanine, the 24’x10’ 4-wall modular office above, and the 9’x22’9” two wall modular wall system below, and we had yet another very happy customer.
A mezzanine deck thickness between the bottom of the primary framing member and the top of deck.
There are many times when the thickness of a mezzanine needs to be minimized due to various height restrictions. The tightest we could normally provide a storage mezzanine would be one foot between the clearance height underneath and the top of deck. In order to do this though, there are several things we need to consider.
First, we need to consider where the mezzanine is going. Mezzanines in highly seismic regions, such as the Pacific coast, typically require larger and heavier beams than those installed in regions with minimal seismic activity, such as here in northeastern Ohio. This doesn’t necessarily mean that we won’t be able to get the deck thickness down to a foot, but it does make it more difficult.
Next, we’ll want to look at our general design and column layout. The positioning of the columns can greatly affect the size of the beams required and, in turn, the thickness of the mezzanine. What are the required column spans for the project? Typically we like to keep our column spans under 20 feet on center for economic concerns. Longer spans require bigger beams. Often if we’re trying to minimize the deck thickness we might need to go with even shorter spans. We’ll also want to avoid a cantilevered deck if possible, as that too can require a larger beam than normal.
Another thing to consider is bracing on the deck. Generally we have a moment connection between the columns and our framing members by trimming back the wide flange I-beam and bolting it directly to the side of the column without requiring knee bracing. While trying to minimize the thickness of the mezzanine, we might ask you if we can use “tabs”. These are typically 14” long by 4” high pieces of angle that we attach below the primary framing members at the columns. This is particularly important when trying to keep the thickness of the mezzanine to just a foot, as there just isn’t enough beam to make a good solid connection. We might be able to provide a mezzanine with 7’ clear and an 8’ top of deck, but at the columns above the baseplates you’ll have a piece of angle coming 4” off of that 7’.
The final thing to consider is price. Minimizing the thickness of the mezzanine will increase the price. The beams might be smaller, but they are heavier. We might need to use more columns than usual. We might have to replace all “C” section secondary framing members with structural steel beams. All this extra steel adds to the cost. On average, most of the mezzanines we provide have a deck thickness of 1’3” or 1’5”. If the extra couple inches are critical then by all means go for it, but if not, it is usually not worth the added cost.
This is a project we completed in NE Ohio. The customer was looking for space for a secure tool crib for maintenance storage as well as the flexibility to store product. As the product was quite heavy, we utilized the ground floor portion for storing those items and used welded galvanized fencing above to secure their maintenance department’s tool storage. The welded wire fencing was selected because of its versatility. Welded wire partition panels have a weld at each intersection of the wire. In contrast, woven wire generally has the individual wires woven and tied off or welded to a fence frame. The welded wire option is great for most jobs because it can be cut to size in the field. If you measure inaccurately, it is not the end of the world because you can trim the extra length off the panels. Likewise, if there is piping or beams running in the way it is easy enough to cut the welded wire fence panel to accommodate the obstruction, while still maintaining the wire partition panel’s integrity.
We utilized the existing stairs and landing from the building adjacent to the new crib in an effort to cut down cost and avoid taking up more room than necessary on their plant floor. The light you see is a reminder light for the operators of the adjacent crane. It reminds them that the mezzanine and tool crib are there so that they don’t bring their load all the way back to the stop and potentially come in contact with the new structure.
On the front side of the mezzanine, a sliding door was in place for the occasional pallets of materials for maintenance to offload and store. The customer went with a sliding door because it could be opened, a pallet of material could be set on the top of the mezzanine deck and then the sliding door could be closed while the pallet was offloaded. With a hinged gate they would have needed to pull the pallet away from the opening to close the open fall hazard, but that wasn’t going to be feasible due to the bar grating decking.
This customer opted for a simple keyed entry on the hinge door, but they could have used a push button or key card lock with electric strike as well.
Ultimately, they were able to have secure storage for their maintenance department while keeping their product storage below, at a price that fit their budget.