A trailer sitting uncovered through an Indiana winter is not truly resting. Moisture can remain in seams and crevices, repeated freezing and thawing can worsen existing cracks in wood decking, and deicing salt left from the final fall haul can accelerate corrosion on exposed steel and electrical connections. The good news is that sensible winter preparation and a properly installed cover cost far less than replacing damaged decking, wiring, brakes, or structural components.
But not every cover is suitable, and a poorly fitted or improperly supported cover can trap moisture, abrade the finish, collect excessive snow, or tear loose in the wind. Here is how to protect your trailer correctly.
Breathable vs. Waterproof: Why It Matters More Than You Think
Your first instinct might be to buy the thickest waterproof tarp you can find and seal the trailer as tightly as possible. That approach can create a new problem. A non-breathable cover without adequate ventilation may trap humid air underneath it. When temperatures change, water vapor can condense on cold metal, painted surfaces, decking, and hardware. If the cover remains in direct contact with those wet surfaces, drying becomes even slower.
For seasonal storage, look for a durable, weather-resistant cover designed to permit some vapor movement or one that incorporates protected vents. Multi-layer polypropylene and woven polyester covers are common choices, but material alone does not guarantee good performance. The cover also needs secure seams, reinforced attachment points, UV resistance, and enough ventilation to reduce condensation without admitting wind-driven rain or snow.
“Waterproof” and “breathable” are not absolute guarantees. Even a breathable cover can develop condensation during rapid temperature changes, and a water-resistant fabric may eventually leak where snow, ice, or standing water remains on it. The most dependable outdoor arrangement combines a suitable cover with airflow, a sloped support structure, and regular inspection throughout the winter.
If you are covering an enclosed cargo trailer, moisture control matters just as much. Wood floors, interior wall liners, cargo, insulation, and exposed fasteners can retain moisture if the trailer is put away damp. Empty and dry the interior before storage, keep the trailer’s factory ventilation openings unobstructed, and inspect periodically for condensation or leaks.
Sizing the Cover Correctly
A loose cover can billow in the wind, rub through its fabric, damage painted corners, and tear at straps or reinforced openings. A cover that is too tight may split at the seams, place excessive force on rails and ramp gates, or leave parts of the trailer exposed.
Measure the actual trailer rather than relying only on the nominal deck size printed in a listing. Record the body or deck length, overall width at the widest point, and height from the ground to the highest fixed component. Include fenders, side rails, spare tires, toolboxes, winches, folded ramps, roof vents, air conditioners, ladder racks, and other accessories that will remain under the cover. Measure the tongue separately if you intend to cover it.
A trailer described as 6.5 feet by 16 feet has a deck of approximately that size, but its overall dimensions will be greater. Tongue length, fender width, gate design, and installed options vary by manufacturer and configuration, so a single assumed “20-foot cover” will not fit every 16-foot trailer. Compare your measurements with the cover maker’s finished dimensions and fit chart, leaving only the allowance the manufacturer recommends.
For a 20-foot equipment trailer or a Diamond C FMAX gooseneck flatbed, one-piece coverage may require a large custom or semi-custom solution. FMAX trailers are offered in multiple model, length, axle, neck, and deck configurations, so a generic 22- or 24-foot cover should not be selected without measuring the complete unit. In many cases, it is more practical to protect the main deck with a properly supported cover and protect the gooseneck, coupler, toolbox, wiring, and other exposed components separately.
Before ordering, also consider how the cover will pass over sharp corners. Place purpose-made padding or smooth protective material over stake pockets, ramp corners, jack handles, rail ends, and other projections. Do not place a cover over a hot hydraulic power unit, charger, exhaust component, or recently operated bearing or brake assembly.
Tie-Down Strategy for Midwest Winters
Indiana winter weather can bring gusty winds, wet snow, freezing rain, and repeated temperature swings. A cover with inadequate attachment points may fail during the first strong storm. Security should come from several properly placed connections rather than one tightly cinched rope or strap.
The right approach uses multiple attachment points:
- Sewn-in straps under the frame: If the fitted cover includes cross straps, route and buckle them exactly as its instructions specify. Pass them around sound structural areas without pinching brake wiring, hydraulic hoses, breakaway-cable components, light wiring, or suspension parts. Use all required straps and periodically check their tension.
- Elastic or adjustable hem systems: A fitted hem can help keep wind from entering beneath the cover. It should sit securely around the intended perimeter without rubbing against tires, lights, painted corners, or unfinished metal edges. An elastic hem by itself is not adequate for every exposed storage location.
- Supplemental restraint: If the cover manufacturer permits additional straps, use appropriately rated webbing with padding at every contact point. Attach it to suitable frame-mounted locations, not to fragile trim, brake lines, electrical wiring, roof vents, or light brackets. Tighten only enough to control movement; excessive ratchet-strap tension can cut the fabric, distort light components, or damage the finish.
Do not use ordinary rubber bungee cords as the only fasteners for an entire winter. They can lose tension, deteriorate, release unexpectedly, and turn their hooks into projectiles. Purpose-made cover straps or webbing are generally more controllable. Whatever system you use, inspect it after strong winds and after snow or ice has shifted the cover.
Wind abrasion is as important as raw strap strength. A cover that moves repeatedly across paint, aluminum skin, marker lights, or sharp steel edges can cause damage even when it never comes loose. Padding, correct tension, and a close fit reduce this risk.
Snow and Ice Load: What Your Cover Actually Has to Handle
Wet snow can weigh around 20 pounds per cubic foot, although actual density varies substantially. At that illustrative density, two inches of uniformly accumulated snow over a 16-by-8-foot horizontal area would weigh about 427 pounds. Six inches over the same area would weigh about 1,280 pounds. Drifting, rain-soaked snow, refrozen slush, and solid ice can create even more concentrated loading.
That does not mean a fabric cover is designed to support those loads. Fabric weight expressed in grams per square meter describes how much the material weighs; it is not a certified snow-load rating. A 150, 180, or 200 gsm fabric may be more substantial than a lighter product, but its ability to survive winter also depends on fiber quality, coating, seams, support spacing, attachment design, UV exposure, wind, and whether water or snow is allowed to pool.
Create a ridge or other sloped support beneath an open-trailer cover so precipitation sheds instead of forming a basin. Use smooth, stable supports that cannot puncture the fabric, collapse onto the trailer, or create sharp pressure points. Follow the cover maker’s instructions and do not rely on removable ramps, loose boards, buckets, or unsecured poles as supports.
After a significant snowfall, remove loose accumulation promptly with a soft roof rake or broom that will not puncture the cover. Work from the ground whenever possible and avoid climbing onto a snow-covered trailer. Do not strike or forcibly peel frozen fabric, and do not use metal shovels, sharp ice tools, open flames, or boiling water. If ice has bonded to the cover, allow safe thawing rather than tearing the material.
Prepping the Trailer Before the Cover Goes On
The cover cannot compensate for dirt, salt, water, neglected maintenance, or an active leak. Before covering the trailer for winter:
- Clean and dry the trailer. Remove leaves, soil, grease, road film, and deicing chemicals from the deck, frame, suspension, wheels, and accessible undercarriage. Use products appropriate for the trailer’s coating and decking. Rinse thoroughly and allow the entire trailer, including joints and enclosed compartments, to dry completely. Avoid directing high-pressure water into bearings, seals, electrical connectors, hydraulic components, or gaps in wood fibers.
- Inspect the floor and structure. Check wood decking for decay, softness, raised fasteners, splitting, and damage around attachment points. Inspect steel or aluminum floors for distortion, cracks, loose fasteners, and corrosion. Examine welds, ramps, tie-downs, safety chains, the coupler, and the frame. A questionable structural component should be evaluated before the trailer is loaded again.
- Lubricate the specified moving points. Service the coupler, jack, ramp hinges, suspension fittings, hydraulic pivots, and other lubrication points according to the trailer and component manuals. A water-displacing spray is useful for certain short-term applications but is not automatically a substitute for the specified grease or lubricant. Keep lubricants and corrosion products away from brake friction surfaces, tires, wheel studs, and electrical contacts unless the product is approved for that use.
- Service batteries and hydraulics. Dump and tilt trailers may have a hydraulic power-unit battery, and some goosenecks have powered jacks or hydraulic accessories. Fully charge the battery and maintain or store it according to the battery and trailer manufacturers’ instructions. Check the hydraulic system for leaks and leave cylinders and powered components in the recommended storage position.
- Check tire condition and cold inflation pressure. Inflate each tire to the pressure specified for the trailer’s tires and loading by the trailer or tire manufacturer, using the VIN/certification label and tire documentation as applicable. The number molded into a tire sidewall may identify the pressure associated with its maximum rated load; it should not be treated as a universal recommendation for every installation. Check pressure when the tires are cold because ambient temperature affects the reading.
- Park on a stable surface. Concrete, asphalt, or well-drained compacted gravel is preferable to soft soil or vegetation. Chock the wheels securely. Support the jack foot on a broad, sound pad that will not sink during freeze-thaw cycles. Never crawl beneath a trailer supported only by its tongue jack, stabilizer jacks, or improvised blocks.
If practical and permitted by the manufacturer, reduce unnecessary static load in the trailer before storage. Do not leave cargo positioned in a way that overloads one axle or tire for months. Any lifting or long-term frame support must use properly rated equipment at approved support points.
Enclosed Trailers: A Few Different Rules
If you own a Wells Cargo Road Force, a Darkhorse Cargo enclosed trailer, or a Legend enclosed trailer, exterior protection is mainly about preserving the roof, sealants, skin, trim, doors, and finish. The interior needs its own winterization because an exterior cover will not correct an existing roof leak or remove moisture trapped inside.
Empty damp materials, textiles, cardboard, chemicals, and food products before storage. Clean and fully dry the floor and walls. Keep factory roof vents and side vents unobstructed, but close and latch doors unless the manufacturer specifically directs otherwise. Leaving a cargo or ramp door partly open can admit wind-driven rain, snow, pests, and unauthorized entry and can place unnecessary stress on hinges and latches.
Moisture absorbers or rechargeable desiccants can help in a clean, reasonably sealed interior, but they have limited capacity and require inspection or replacement. They are not a cure for water intrusion. Check the trailer periodically for damp flooring, staining, mold, frost, corrosion, and accumulated water.
Inspect roof seams, corner caps, vents, doors, windows, marker lights, roof attachments, and trim before winter. Construction materials differ among manufacturers, models, and production years, and even corrosion-resistant aluminum components can be joined to steel hardware or bordered by aging sealant. Use only a sealant approved by the trailer manufacturer for the specific roof material, existing sealant, and joint. Some self-leveling lap sealants are intended only for horizontal surfaces, while non-sag products are used on vertical joints. Applying an incompatible product over dirt or failed sealant can make a leak harder to repair.
For an enclosed trailer, prevent the cover from blocking designed ventilation or bearing directly on delicate roof vents, antennas, solar panels, air conditioners, or sharp roof edges. Maintain drainage paths and ensure the support arrangement cannot concentrate snow load on the roof skin.
What If You Cannot Store Under Cover at All?
Not every situation permits a full trailer cover. The trailer may be too large, have an irregular equipment configuration, or require regular access throughout winter. If full coverage is impractical, at minimum:
- Clean the trailer thoroughly and keep salt and deicing chemicals from remaining on the frame, suspension, wheels, deck, and Diamond C DM Difference Maker multi-stage coating.
- Treat wood decking only with a product compatible with the wood and any existing treatment, following its preparation, temperature, drying-time, and reapplication instructions. Do not apply a sealer over wet, frozen, dirty, or decayed boards.
- Use a compatible corrosion inhibitor on approved bare or exposed metal areas. Never spray it onto brake drums, rotors, pads, shoes, magnets, tires, wheel studs, walking surfaces, electrical grounding points, or any component whose manufacturer prohibits the coating.
- Park on a firm, well-drained surface away from standing water, vegetation, roof runoff, unstable slopes, and trees with hazardous limbs. Maintain safe access for inspection and snow removal.
- Protect the coupler and electrical connector with fitted, ventilated products designed for those components. Clean the connector, allow it to dry, and use connector-compatible dielectric protection where recommended. Do not tightly wrap damp electrical parts in household plastic, which can trap condensation.
- Inspect the trailer throughout winter, especially after wind, ice, heavy snow, or flooding. Wash off newly accumulated road salt promptly if the trailer remains in service.
This is the practical minimum. A roofed, well-ventilated structure on a stable surface generally provides better long-term protection than a fabric cover, while a correctly fitted and maintained cover is preferable to leaving vulnerable surfaces completely exposed.
Covers Worth Buying (and One Thing to Avoid)
Cover prices and product availability change frequently, and many products marketed for “trailers” are actually shaped for travel trailers, boats, or recreational vehicles. Buy according to measured dimensions, intended outdoor exposure, fabric construction, venting, attachment system, warranty, and the manufacturer’s stated application rather than brand name alone.
A practical comparison looks like this:
| Cover Type | Best For | Typical Buying Considerations |
|---|---|---|
| Fitted breathable utility-trailer cover | Open utility trailers within the maker’s published size range | Check finished dimensions, reinforced corners, vents, underbody straps, UV resistance, and clearance for rails and ramp gates |
| Heavy-duty semi-custom outdoor cover | Open equipment trailers and irregular configurations | Confirm fabric compatibility, support requirements, warranty terms, attachment locations, and whether the cover is intended for snow exposure |
| Heavy woven tarp system | Short-term or carefully supported use | Requires a sloped framework, secure tie-downs, ventilation, edge padding, drainage, and frequent inspection; generic sizing increases wind abrasion |
| Custom-patterned cover | Enclosed cargo trailers, specialty bodies, and large gooseneck configurations | Usually provides the closest fit but must account for vents, accessories, sharp projections, separate neck coverage, and access points |
Lightweight blue polyethylene tarps are usually a poor choice for season-long exposure. Their grommets and edges can fail in wind, the material may abrade paint, and an unvented installation can trap condensation. If a tarp is used temporarily, it still needs smooth support, a slope for drainage, padding, secure attachment, and routine inspection. No cover should be allowed to flap against the trailer or form a pond above the deck.
Before purchasing, read the warranty exclusions. Some manufacturers exclude damage caused by pooled water, snow accumulation, improper support, contact with sharp objects, high winds, or installation over accessories. A heavier or more expensive cover is not automatically suitable for an unsupported winter installation.
Spring Removal and What to Check
When you remove the cover in March or April, choose a dry, calm day. Clear loose snow, ice, and standing water first. Release the restraints gradually so wind cannot catch the fabric. Inspect the cover for tears, worn areas, failed stitching, damaged straps, mildew, and abrasion marks. Clean it only by the method permitted on its care label and store it completely dry. Machine washing, harsh detergent, bleach, high heat, or pressure washing can damage some coatings and seams.
Then inspect the trailer before the first haul of the season. Examine the coupler, safety chains, breakaway switch and cable, jack, ramps, frame, welds, decking, tie-down points, suspension, and tires. Look for corrosion, cracking, leaks, rodent damage, and deteriorated wiring. Test the seven-way connector, running lights, turn signals, brake lights, and electric or electric-over-hydraulic braking system with the trailer connected to a compatible tow vehicle.
Check cold tire pressure, tread condition, sidewalls, valve stems, and date codes. Inspect wheel bearings and seals according to the axle manufacturer’s maintenance schedule. Check wheel-fastener torque with a calibrated torque wrench using the wheel, hub, and axle manufacturer’s specified value and tightening sequence. Wheel nuts require rechecking after wheel installation and during the prescribed break-in mileage; winter weather alone is not a reason to guess at a torque value or overtighten them.
On Diamond C trailers equipped with Lippert axles, follow the applicable Lippert service information along with the trailer’s documentation. Electric drum brakes require inspection and adjustment at the specified intervals, and newly installed shoes or magnets require the manufacturer’s burnishing procedure. Brake service should be performed by a qualified technician if you are not equipped to inspect the assemblies safely.
If you are not sure what shape your trailer is in heading into spring, bring it by Spencer Trailers at 291 West State Hwy 46 in Spencer. We can walk through the basics with you. And if winter did its worst on an older unit, take a look at our current inventory to see what Diamond C, H&H, Liberty, and others have available this season.
A suitable cover is one of the more affordable trailer-protection purchases you can make, but it works only when the trailer is clean and dry, the fabric is properly supported, the attachment points are secure, and snow and condensation are monitored. Trailers that deliver long service in the Midwest are the ones whose owners control moisture and salt, follow the component manufacturers’ maintenance schedules, and inspect them throughout storage rather than simply covering them in the fall and forgetting them until spring.
