A retractable tonneau cover is a popular truck bed cover that rolls up or folds for easy access to the truck bed. Unlike soft roll-up or folding covers, retractable tonneau covers are made of hard materials like aluminum or reinforced vinyl that provide increased durability and security. However, the retractable design requires a certain amount of clearance to open properly. So what is the minimum height required?
How Retractable Tonneau Covers Work?
Retractable tonneau covers have a canister that houses the cover material when retracted. The cover rolls or folds into this canister, which is mounted at the front of the truck bed against the cab. When closed, the cover extends from the canister to the tailgate, keeping the bed covered.
To open a retractable tonneau, you release the latches and the cover retracts into the canister. This allows complete access to the full truck bed without having to remove the tonneau cover. The cover glides along rails or tracks as it opens.
Factors That Determine Minimum Height
There are a few key factors that determine the minimum height required to open a retractable tonneau cover:
Canister Placement
The placement and size of the canister play a big role. Lower profile canisters mounted closer to the top of the truck bed will require less open height than larger canisters.
Lowest Point of Latching Mechanism
The latching mechanisms are often the lowest point on the cover when retracted. On some covers, the latches may be lower over the stake pockets, requiring their covers to be removed for clearance.
Amount of Cover Material Rolled Up
Covers with reinforced vinyl will roll up smaller than aluminum covers when retracted. Less material to store in the canister means less height required.
Cargo in Truck Bed
The cargo loaded in the truck bed is also a consideration. Taller items may require more headroom to open the cover than low-profile cargo.
Examples of Minimum Heights for Retractable Covers
Here are some real-world examples of the minimum heights required for various retractable tonneau cover models:
Undercover UltraFlex
- 15 inches from top of bed ridges to lowest point of latching mechanism in center of bed.
Mountain Top EVO-M Retractable Hard Tonneau Cover
- Lowest point is over stake pockets, so their covers need removed to open cover fully.
Roll-N-Lock LG220M Locking Retractable Tonneau Cover
- Approximately 16 inches required from top of bed side rails. Low-profile canister design.
Pace Edwards Switchblade Retractable Tonneau Cover
- Minimum height around 18 inches with cover partially retracted over cargo.
RetraxPRO MX Retractable Tonneau Cover
- About 14 inches required at lowest latch point to open cover.
BAK Revolver X4S Retractable Hard Tonneau Cover
- Roughly 15 to 16 inches needed for clearance with side latches lowered.
As you can see, most retractable covers require 14 to 18 inches of clearance from the top of the bed rails to open properly. However, the minimum height can vary a couple inches depending on specific model.
Tips for Measuring Height Before Purchase
If you’re looking to buy a retractable tonneau cover, here are some tips for measuring to ensure you get a model that will open properly in your truck:
- Measure from top of bed rails to lowest point over stake pockets.
- Account for any existing accessories like a bedliner, bed rail caps, or a toolbox that may reduce inside bed height.
- Check your usual cargo items to see if they will limit clearance.
- Look at canister size and placement in product images and specs. Lower profile and more forward mounting requires less height.
- Search for the cover name and “minimum height” to find any specs published by manufacturers.
- Contact seller or manufacturer to request exact minimum height numbers if not found online.
Taking accurate measurements beforehand and researching clearances will help you choose the best retractable tonneau that will open without issues.
Factors That Can Reduce Clearance Over Time
While retractable covers are designed to open smoothly when installed properly, there are some factors that can reduce clearance over time:
Bowing or Sagging Cover
Vinyl covers can stretch and bow over years of use, drooping in the center when closed. This effectively reduces the open height.
Dislodged or Misaligned Canister
The canister and rail system may get knocked out of alignment, allowing the cover to sit lower when closed. Opening height will be reduced.
Bulky Cargo Items
Loading heavier or irregularly shaped items in the bed that weren’t accounted for originally can limit retractable clearance.
Accumulated Debris and Dirt
Build up of leaves, dust, snow, ice and other debris on the cover and rails can take up valuable inches. Regular cleaning helps avoid this.
Damaged or Worn Components
Dents, cracks or damage to the canister, rails, seals or cover material itself will prevent smooth retraction and lower the cover.
Performing periodic inspections and maintenance will maximize the open clearance over time.
Options for Low Clearance Truck Beds
What if you have a truck with an extra shallow bed or obstructions that prevent retractable covers from opening fully? There are still some options:
Roll or Folding Covers
Soft vinyl roll-ups or folding covers have more flexibility for tight spaces since they roll or collapse vertically instead of into a canister. Just avoid models with frame bows.
Low-Profile Retractable
Some retractables like the BakFlip MX4 are as low as 12 inches for the housing. Measure carefully to see if one will work.
Raise Mounting Points
Using a riser system or special mounting brackets to lift the canister higher on the bed may add the needed inches.
Limit Cargo Height
Keep cargo low enough to preserve the margin you need for opening the retractable cover.
With careful measurement, research and installation, retractable tonneau covers can be made to work on most truck beds. But for those with tight clearances, alternative covers may be required.
The Minimum Height Depends on Your Specific Tonneau Cover and Truck Bed
The bottom line is that the exact minimum height required to open a particular retractable tonneau cover will depend on the specific model and the unique dimensions of your truck bed.
There is no universal number that applies to all covers and trucks. The easiest way to determine if a retractable will function correctly is to obtain the minimum height spec from the manufacturer or seller and compare it to measurements you take of your unobstructed truck bed.
Accounting for your usual cargo is also important. Allowing a few extra inches of clearance beyond the bare minimum spec will prevent frustrations with opening the cover. Careful shopping, measuring and research upfront will ensure you choose a quality retractable tonneau cover tailored to your truck that provides years of smooth, unhindered opening and closing.Copy