ShadeMart 21 ft x 24 ft Grey Rectangle Sun Shade Sail - UPF50 Coverage

In this review of the ShadeMart 21' x 24' grey rectangle sun shade sail, the bottom line is straightforward: this is a practical, heavy-duty shade solution for patios, carports, pools and boats where UV protection and airflow matter most. The reviewer found the woven HDPE fabric blocks up to 95% of harmful UV rays while remaining water permeable and breathable, so it cools the covered area without trapping rain. If you need a large, sturdy canopy that straps to posts, walls or trees and can be custom sized, this sail is worth considering.

Key Features

• Woven HDPE fabric: provides durable sun protection while remaining breathable so heat does not build up under the sail.
• UPF50 sun blocking: blocks up to 95% of harmful UV rays which helps lower temperatures under the sail by roughly 10 to 15 degrees.
• Stainless steel D rings: heavy duty corner D rings attached to white webbing give secure anchor points and resist corrosion outdoors.
• Water permeable: the sail sheds rain by allowing water to pass through the weave rather than pooling on the fabric surface.
• Custom sizing available: multiple custom sizes allow fitting to irregular venues, provided you measure the installation area accurately.
• Versatile mounting: with appropriate hardware the sail can be attached to poles, walls, roofs or trees for patios, carports and pool areas.

Who It's For

This shade sail is best for homeowners or small business owners who want a large, breathable canopy for outdoor living spaces, carports, boat covers or poolside shade. It suits people who value UV protection and airflow over full waterproofing and who have anchor points like posts, walls or trees available.

Those seeking a fully waterproof shelter, or a rigid structure for extreme weather, should look elsewhere; this style is explicitly water permeable and not designed to stop heavy rain from passing through. Buyers should also be prepared to measure carefully if ordering a custom size to ensure proper fit.

Pros & Cons

Pros

• Durable woven HDPE fabric that holds up in wind and resists tearing.
• High UV protection up to 95% which noticeably cools shaded areas.
• Stainless steel D rings and heavy webbing provide reliable anchoring points.
• Permeable design prevents water pooling and allows airflow beneath the sail.

Cons

• Not waterproof, so it will not keep an area dry during steady rain.
• Sizing can vary slightly due to manual measurements, so accurate venue measuring is necessary.

Specifications

Brand	ShadeMart
Shape	Rectangle
Size	21' x 24'
Material	Woven HDPE (High Density Polyethylene)
UV Protection	Blocks up to 95% (UPF50)
Corners	Stainless steel D rings on heavy duty webbing
Water Performance	Water permeable and breathable (not waterproof)

Our Verdict

The ShadeMart 21' x 24' grey rectangle sun shade sail is a practical, value-oriented choice for anyone who needs broad UV protection and airflow for patios, pools, carports or boats. It is well suited to outdoor areas with existing anchor points and offers sturdy hardware and fabric that customers report holds up in wind and hail. Choose this sail when cooling, durability and custom sizing are priorities rather than a waterproof canopy.

Frequently Asked Questions

Is this sail waterproof?
No. The fabric is water permeable and breathable, so it allows water to pass through rather than acting as a waterproof cover.

How much UV protection does it provide?
The sail blocks up to 95% of harmful UV rays (UPF50), which significantly lowers temperatures under the canopy.

Can it be attached to trees or poles?
Yes. With the proper hardware kits it can be anchored to poles, trees, walls or roofs for patios, carports, pergolas and more.