ShadeMart 16 ft x 21 ft Red Sun Shade Sail - UPF50 Rectangle Canopy

In this review of the ShadeMart 16 ft x 21 ft Red Sun Shade Sail the bottom line is simple: this is a heavy-duty, breathable rectangle canopy best for homeowners who need reliable UV protection and large-area coverage for patios, carports, or poolside shade. The strongest reason to buy is the fabric and construction - woven HDPE blocks up to 95% of harmful UV while remaining water permeable and breathable, so it cools outdoor spaces without trapping heat. The review covers usability, durability, and real customer impressions.

Key Features

• Woven HDPE fabric: provides high UV resistance while remaining breathable so the area beneath stays cooler and ventilated.
• Stainless steel corner D rings: attached to heavy duty white webbing for secure, low-corrosion anchor points that hold up in outdoor conditions.
• Water permeable design: allows rain and air to pass through the sail so water does not pool and wind loads are reduced.
• Large rectangle coverage: the 16 ft x 21 ft size offers substantial shade for patios, carports, or pool areas and can lower temperatures noticeably under the sail.
• Custom size options: ShadeMart offers a selection of custom sizes so buyers can match irregular venues when precise fit matters.

Who It's For

The ShadeMart 16 ft x 21 ft rectangle sail is ideal for homeowners and renters who want a durable, high-coverage shade solution that blocks most UV and improves comfort on a patio, over a pergola, or above a carport. It suits DIY installers who can anchor the sail to poles, trees, walls, or roofs using appropriate hardware kits and who appreciate a breathable, non-waterproof canopy.

Those who should look elsewhere include buyers who need a waterproof solution or who require an exact factory-cut fit without any measurement tolerance; this style is explicitly not waterproof and customers should measure carefully because manual size variations can occur.

Pros & Cons

Pros

• Excellent UV protection, blocking up to 95% of harmful rays for safer outdoor time.
• Durable construction with woven HDPE and stainless steel D rings for long service life in outdoor conditions.
• Breathable and water permeable, preventing water pooling and reducing wind stress on attachment points.

Cons

• Not waterproof, so it will not keep out heavy rain and is intended only for shade and UV protection.
• Size variations from manual measurement mean buyers must verify dimensions carefully before ordering.

Specifications

Product shape	Rectangle
Size	16 ft x 21 ft
Material	Woven HDPE (High Density Polyethylene)
Corner hardware	Stainless steel D rings on heavy duty white webbing
Water resistance	Water permeable, not waterproof
UV protection	Blocks up to 95% of UV rays (UPF50)
Custom options	Custom sizes available

Our Verdict

The ShadeMart 16 ft x 21 ft Red Sun Shade Sail is a practical buy for anyone who needs a large, durable shade canopy that cools outdoor spaces and blocks most UV. It offers good value through sturdy materials and breathable design, but it is not a waterproof cover, so buyers who need rain protection should choose a different product.

Frequently Asked Questions

Is this shade sail waterproof?
This style is water permeable and breathable, not waterproof, so rain will pass through rather than be shed.

Will it block the sun effectively?
Yes, the woven HDPE fabric blocks up to 95% of harmful UV and noticeably reduces temperature under the sail.

Can I customize the size?
ShadeMart offers a selection of custom sizes; measure the installation area carefully because manual measurements may vary.