What No One Tells You About Specifying Perforated Panels (And Why My Team Almost Got It Wrong)

If you're specifying perforated panels or plank grating and you haven't verified the open area percentage, the hole pattern, and the material thickness against your load requirements—stop now. That one oversight cost my company about $3,200 in rework and a lot of lost time. I'm not an engineer (I manage purchasing), but after 5 years handling orders for industrial materials across 3 locations, I can tell you: the specs on the page and the product on the dock are sometimes two different things. Here's what I've learned about getting it right with McNichols products.

My Starting Point: A Painful Lesson in Specs

In 2023, I was sourcing replacement treads for a mezzanine project. Our engineering team had approved a specific McNichols perforated panel spec: 16-gauge, 1/2" round holes on 3/4" staggered centers. The price from a new vendor was fantastic—about $2,100 less than our usual quote. I placed the order (60 panels, 4' x 8'). Two weeks later, they arrived.

The problem? The hole pattern was correct, but the material was 18-gauge. The vendor said that's 'standard' for that pattern. It wasn't what we specified. Our engineer rejected them because they didn't meet the load capacity. I had to eat about $1,100 in return shipping and re-order from the original source (thankfully, McNichols stocked the right spec). The lesson was expensive.

Most buyers (myself included, once) focus on the obvious: price and panel size. They miss the details that actually make the product work.

What Actually Matters When You're Ordering Perforated Panels or Plank Grating

Here's the checklist I use now:

1. Open Area Percentage Isn't Optional

This one's a big deal. The % open area directly affects drainage, airflow, and light transmission. If you're using perforated panels for a safety barrier or a walkway, a slight difference changes the structural integrity. McNichols has detailed spec sheets on this (seriously, use them). For example, their standard 1/2" round on 3/4" staggered in 16-gauge gives about 40% open area. Drop to 18-gauge and that percentage changes (because of edge distortion at the punch). I check McNichols' published data against the actual material certificate before I cut a PO.

2. Plank Grating: It's Not All the Same

Our facility manager loves McNichols plank grating for the service platforms in the warehouse. I've ordered both the aluminum and the fiberglass versions. The mistake some of my colleagues in other companies make? Assuming all 'plank grating' is interchangeable. The load tables are totally different between metal and FRP (fiberglass). You can't just swap them without re-engineering. Also, the bearing bar spacing (like 1-3/16" vs. 2-3/16") matters for things like heel-proofing and load distribution. I always verify the specific load table for the exact product code before ordering.

3. Custom Fabrication: The Hidden Trap (and Solution)

A lot of us in purchasing think 'cut-to-size' means cut exactly to my drawing. I've learned (the hard way, ugh) that you need to be specific about tolerances. For a recent project needing perforated panels with specific cutouts, I used McNichols' custom fabrication service. Their quoting team asked about edge finishing, hole tolerances, and deburring. I didn't know that was a thing. The upside? We got exactly what we needed, no field modifications. The risk was the lead time (which was 4 weeks, not 2). I kept asking myself: is the perfect fit worth the extra 2 weeks? For that job, yes. For a rush repair, maybe not.

The Real Cost Isn't Always on the Invoice

If you're a buyer or a specifier, here's what I wish someone had told me early on:

• The cheapest quote doesn't exist if you have to rework the order. That $2,100 'savings' I mentioned? My actual cost was negative when you include the return freight, the re-order premium, and the lost labor.
• Verify the certification. For any grating or perforated panel used in a load-bearing application, ask for a material test report (MTR) or compliance cert. McNichols provides these. A vendor who hesitates? Red flag.
• Shipping damages happen. Perforated panels can warp or get bent in transit. We had a shipment of 10" wide planks arrive with a bent edge (circa 2024). Inspect on receipt. Don't sign off until you've checked the first few.

When This Advice Doesn't Apply

Honestly, this level of scrutiny is overkill if you're buying decorative panels for a non-structural facade or a simple shelf. If the application is cosmetic and the loads are near-zero, then price and lead time are your main drivers. Also, if you're working with a local distributor who stocks the exact product and you can see it, touch it, and verify it yourself, you can relax a bit. But for anything that involves people walking on it, loads being applied, or critical safety, do the homework on the spec.

Per FTC guidelines (ftc.gov), make sure your claims about product performance are substantiated. My experience is just that: my experience. Your engineering team should always verify the final application. But from a purchasing perspective, I can tell you the McNichols catalog and their spec sheets are a solid starting point. Just don't stop there.