Flatbed dunnage and v-boards: protecting straps, freight and your record

Flatbed dunnage and v-boards are the cheapest part of a securement system and the part most often left in the truck stop parking lot. A corner protector that costs a few dollars keeps a strap from being cut and finished freight from being crushed under it. They also come up on the record: FMCSA's roadside data for September 2024 to September 2026 shows 1,789 citations for missing edge protection (our securement violations analysis has the rest). Here is when the rules require them, when shippers do, and which piece fits which freight.

When edge protection is required

The federal rule is short. A tiedown that would be subject to abrasion or cutting where it touches the cargo must be protected, and the protection itself has to resist abrasion, cutting and crushing (49 CFR 393.104(f)(4)). Two more rules in the same section matter:

• Damaged tiedowns, including straps already cut or worn, are not allowed (393.104(b)).
• A tiedown must not be able to come loose, which an edge that slowly saws through a strap will eventually cause.

So the test is simple: wherever a strap or chain meets a sharp, hard or rough edge, put something between them that will not be cut itself. A folded piece of cardboard does not pass.

When shippers require it

Shippers often go further than the rule, because their concern is the freight. Common shipper rules:

• Edge protection under every strap, even on smooth freight, to prevent strap marks on finished goods.
• V-boards full length on lumber, boxed or palletized building products.
• No chain on finished surfaces, or chain only with sleeves.
• Their own dunnage under each bundle or coil, sometimes with a charge to the carrier.

These are not in the regulations, but a load that arrives with strap damage turns into a claim against you. Ask before you book; load board posts rarely say.

Which protector for which freight

Prices are one retailer's listings (Trucking Depot, October 26, 2026), not a market average. Our flatbed gear checklist has the whole kit with quantities.

Dunnage: blocking, spacers and mats

Dunnage is everything under and around the freight that is not a tiedown. On a flatbed it usually means:

• Hardwood blocks (4 x 4 in or larger) under bundles and machines so forks and crane slings can get under them, and so freight sits on wood instead of a slick deck.
• Spacers between tiers of lumber. When bundles are stacked on spacers, the spacers must support every piece in the bottom row above and be at least as wide as they are tall (393.118). Our lumber loads guide covers the stacking rules.
• Chocks, wedges and cradles for anything likely to roll: pipe, round stock, wheeled equipment. This one is required (393.106(c)).
• Coil bunks and racks. For metal coils of 5,000 lb or more with the eye crosswise or lengthwise, timbers and chocks must be held by bunks or similar devices; nailed blocking as the only means and nailed wood cradles are prohibited (393.120). See hauling steel coils.
• Pipe blocking. Concrete pipe blocking must be at least 4 x 6 in timber, placed symmetrically and held firmly against the pipe (393.124).
• Friction mats between freight and deck or between tiers. An unmarked mat is treated as resisting horizontal movement equal to 50% of the weight on it (393.108). Mats help; they never replace the tiedowns.

How to use them well

1. Place protection before you tension. A protector slid in after the strap is tight usually ends up crooked or missing.
2. Center the strap on the protector so it cannot walk off the edge as the load settles.
3. Re-check them at your first stop within 50 miles and at each later check. Protectors blow off, especially on tarped loads where you cannot see them.
4. Replace cracked protectors. A broken plastic protector can cut a strap faster than no protector.
5. Keep dunnage dry and clean. Wet, oily or rotten blocks slide and split.
6. Count it as gear. Carry more corner protectors than straps; they get lost at every delivery.

For the freight these rules show up on most, see the flatbed loads we book; for posts that leave out the details, our flatbed load boards guide covers which questions to ask. More guides are on the guides page.