20 x 40 20 Mil Heavy Duty Tarp Cover - Waterproof UV Resistant

In this review the 20 x 40 20 mil tarp is evaluated as a heavy-duty, multipurpose cover suited for outdoor protection. The bottom line: this tarp is for homeowners, contractors, and campers who need a full-size, thick poly tarpaulin that resists water and sun damage. Our review found the finishing size promise and reinforced edges to be the tarp's single biggest advantage, giving confidence when covering roofs, boats, patios or work areas where a true 20 x 40 tarp is required.

Key Features

• Finished size: The tarp is supplied at the full stated dimensions so buyers get a true 20 x 40 cover without losing inches at the edges.
• 100% virgin polyethylene: Made from nonrecycled material which increases longevity and helps the sheet resist tearing and rotting compared with mixed-material tarps.
• Reinforced edges: Hemmed and strengthened sides reduce fraying and help the tarp hold up under tension when tied down.
• Metal grommets every 18 in: Frequent grommets make it easier to secure the tarp tightly with rope or bungees, improving wind resistance.
• Waterproof and UV resistant: The thick poly construction keeps rain out and reduces sun damage for year-round outdoor coverage.
• Multipurpose use: Large format and robust build make it suitable for roofs, camping shelters, pools, boats, and protection during painting or renovation.

Who It's For

This tarp is best for homeowners protecting roof patches, contractors needing a large temporary cover, and campers who prefer a heavy, durable ground or shelter tarp. The true finished size is especially useful when exact coverage matters and when overlapping smaller tarps would be inconvenient.

Those who need a lightweight, packable emergency tarp or an aesthetic patio canopy may prefer a thinner, lighter model; similarly, buyers looking for industrial-grade anchoring systems should ensure their tie-down plan accounts for the frequent grommets and reinforced hem rather than expecting built-in straps or corners designed for repeated heavy load cycles.

Pros & Cons

Pros

• Very sturdy feel from the 20 mil thickness and virgin polyethylene construction.
• Reliable coverage with a true finished 20 x 40 size that removes guesswork when measuring.
• Frequent metal grommets and reinforced edges make tying down straightforward and secure.
• Effective waterproofing and UV resistance for long seasonal exposure.

Cons

• Some users report grommet tearout under extreme strain, so extra care or additional reinforcement may be needed for heavy permanent installations.
• The tarp is heavy and less convenient to carry or store for ultralight backpacking use.

Specifications

Brand	Core Tarps
Finished size	20 x 40 ft
Thickness	20 mil (approximate heavy duty poly)
Material	100% virgin polyethylene
Weave count	16 x 16
Grommet spacing	Every 18 in
Color	Brown/Black

Our Verdict

The 20 x 40 20 mil tarp is a practical choice for anyone needing a heavy, true-size cover that stands up to rain and sun. It offers strong value for roof patches, jobsite protection, boat and pool coverage, and large camping shelters, though buyers should reinforce tie points for permanent, high-tension use. Overall it is a rugged, cost-effective tarp for general outdoor protection.

Frequently Asked Questions

Is this tarp truly waterproof?
Yes, the thick polyethylene construction is waterproof and designed to block rain and moisture in normal outdoor use.

How close are the grommets spaced?
Metal grommets are placed every 18 in to give many secure tie-down points across the sheet.

Will the grommets hold under strong winds?
The reinforced edges help, but some customers report grommet tearout under extreme strain so additional reinforcement is recommended for permanent high-wind installations.