ShadeMart 12ft x 21ft Blue Sun Shade Sail UPF50 Rectangle - Breathable

In this review of the ShadeMart 12ft x 21ft Blue Sun Shade Sail the bottom line is simple: this rectangle canopy is for homeowners and small-business users who want large, breathable UV protection without a hard roof. The reviewer found it especially useful for patios, carports and poolside shade because the woven HDPE fabric blocks up to 95% of UV while remaining water permeable, which prevents pooling and reduces ambient temperature by roughly 10 to 15 degrees. Installation is straightforward with proper hardware, and the heavy duty D rings and webbing feel robust for outdoor use.

Key Features

• Material: woven HDPE fabric provides a sturdy, lightweight canopy that stands up to sun exposure without trapping heat.
• UV protection: blocks up to 95% of harmful rays so shaded areas stay noticeably cooler for comfort and sun safety.
• Water permeability: breathable, water permeable weave allows rain and air to pass through, preventing sagging and water pooling.
• Hardware quality: stainless steel corner D rings attached to heavy duty white webbing give secure anchor points that resist corrosion.
• Custom sizing: available in multiple sizes, allowing buyers to choose a sail to fit patios, carports, pergolas and more when measured accurately.
• Styling: rectangle shape and color options make the sail a decorative addition that integrates with outdoor design.

Who It's For

The shade sail is ideal for homeowners with patios, pool areas or carports who need strong sun protection and prefer a breathable, decorative canopy rather than a solid roof. It suits renters and DIY installers who can attach the sail to existing structures like poles, walls or trees using the right hardware.

Those who need a fully waterproof cover or an exact factory-cut rectangle may want to consider other options; the fabric is intentionally water permeable and custom sizes are subject to manual measurement variance, so exact dimensions should be checked before ordering.

Pros & Cons

Pros

• High UPF and sun blocking capability that meaningfully reduces temperatures in shaded areas.
• Durable construction with stainless steel D rings and heavy webbing for reliable anchoring.
• Breathable, water permeable fabric avoids pooling and performs well in variable weather.
• Custom size options and attractive rectangle styling work well for many outdoor spaces.

Cons

• Not waterproof by design, so it will not keep an area dry during heavy rain.
• Some buyers report size variations and slight deviation from a perfect rectangle due to manual measurement.

Specifications

Our Verdict

The ShadeMart 12ft x 21ft rectangle shade sail is a practical, good-value option for anyone needing large, breathable sun protection that also looks attractive over a patio, pool or carport. Its UPF50 performance, durable D rings and water-permeable weave make it especially well suited to outdoor living spaces, though buyers should measure carefully since sizes are customized and the sail is not intended to be waterproof.

Frequently Asked Questions

Is this shade sail waterproof?
No, the fabric is water permeable and designed to allow water and air through rather than provide a waterproof cover.

Can it be attached to trees, poles or walls?
Yes, with proper hardware kits it can be anchored to poles, trees, walls or roofs; use secure fittings for safety.

How much UV protection does it offer?
The sail blocks up to 95% of harmful UV rays and is rated at UPF50, which reduces sun exposure and helps lower temperatures beneath the canopy.