ShadeMart 17 ft x 21 ft Green Sun Shade Sail UPF50 Rectangle - Durable

In this review the ShadeMart 17' x 21' green rectangle sun shade sail is evaluated for anyone who needs broad, breathable UV protection for a patio, carport, or RV cover. The biggest reason to buy is its balance of durable woven HDPE fabric and stainless steel corner D rings that deliver a sturdy, weatherresistant canopy that still allows water and air to pass through. The sail is intended for shade and heat reduction rather than waterproofing, and it stands out for blocking a large portion of UV while remaining easy to install with the right hardware.

Key Features

• Woven HDPE fabric: The high density polyethylene weave provides effective sun blockage while remaining breathable so heat and moisture do not build up underneath.
• UPF50 sun protection: Blocks up to 95% of harmful UV rays and significantly lowers temperatures beneath the canopy for more comfortable outdoor time.
• Stainless steel corner D rings: Heavy duty D rings attached to reinforced white webbing make anchor points strong and resistant to corrosion.
• Water and air permeable: The sail allows water to pass through rather than pond, reducing wind load and the chance of damage in rain events.
• Custom size options: Multiple sizes are available and ShadeMart will customize sails to fit nonstandard venues when measurements are provided.
• Decorative rectangle styling: The simple rectangle shape integrates with many outdoor designs and upgrades visual appeal while providing functional shade.

Who It's For

The ShadeMart 17' x 21' rectangle sail is best for homeowners with a patio, pergola, pool area, carport, or RV who want a durable, breathable shade solution that lowers temperature and blocks UV. It is also a good option for renters who can attach a sail to temporary anchors like poles or trees when permanent structures are not available.

People who need a fully waterproof canopy or an exact color match for a precise design palette should look elsewhere; this style is not waterproof and color can vary in customer reports. Also measure your mounting area carefully because manual measurements can create small size variances.

Pros & Cons

Pros

• Durable woven HDPE construction provides reliable sun protection and long wear.
• Stainless steel D rings and reinforced webbing give secure, corrosion resistant attachment points.
• Breathable, water permeable design prevents pooling and keeps air moving underneath.

Cons

• Not waterproof, so it will not shelter from heavy rain.
• Color can vary from expectations and some buyers have reported differences from product images.

Specifications

Our Verdict

The ShadeMart 17' x 21' green rectangle sun shade sail is a practical, value oriented choice for shading patios, carports, pools, and RVs where breathability and UV protection matter more than waterproofing. Its heavy duty fabric and stainless steel fittings make it durable and relatively easy to install with the right anchors, offering strong performance for most outdoor shading needs.

Frequently Asked Questions

Is this shade sail waterproof?
No. This style is water permeable and breathable, so it allows water to pass through rather than providing a waterproof shelter.

Will it block UV and reduce heat?
Yes. The woven HDPE fabric offers UPF50 protection and can block up to 95% of harmful UV, helping lower temperatures underneath the sail.

Can it be customized to other sizes?
Yes. ShadeMart offers custom sizes but you should measure your venue accurately because manual measurements can cause small variances.