18ft x 20ft Green Sun Shade Sail UPF50 Rectangle - Breathable Canopy

In this review the ShadeMart 18' x 20' green rectangle shade sail is assessed for homeowners and small business owners who need durable sun protection without trapping heat. The bottom line: this woven HDPE canopy delivers effective UV reduction and airflow, making it a practical choice for patios, carports and poolside covers. The review focuses on build quality, shading performance and ease of installation so you can decide if the breathable, water permeable design fits your outdoor space.

Key Features

• Woven HDPE fabric: The material blocks up to 95% of harmful UV rays while remaining breathable to keep the shaded area noticeably cooler.
• Stainless steel D rings: Heavy duty corner D rings attached to white webbing provide secure anchor points for a stable installation.
• Water permeable design: The canopy allows water and air to pass through, preventing puddles and reducing wind sail effect during storms.
• Custom size options: A wide selection of sizes lets you order a fabric area that matches your measured venue for a tailored fit.
• Rectangle styling: The simple shape and multiple color choices make it easy to integrate the sail with existing outdoor decor.

Who It's For

This shade sail is ideal for homeowners who want reliable sun protection over patios, pergolas or carports while preserving airflow. It suits poolside areas, yards and boat covers where ventilation and UV blocking are priorities rather than full waterproofing.

It is less suitable for buyers seeking a fully waterproof roof or a rigid structure; if you need a hard, watertight canopy or permanent roofing, consider a different product designed for full waterproofing and load-bearing support.

Pros & Cons

Pros

• Blocks up to 95% of UV rays while lowering temperatures thanks to breathable woven HDPE fabric.
• Durable hardware with stainless steel D rings and heavy duty webbing improves longevity and secure mounting.
• Water permeable construction avoids pooling and reduces wind stress compared with solid canopies.
• Custom sizing and multiple colors allow for tailored installations and better visual integration.

Cons

• Not waterproof, so it will not keep out rain for fully covered outdoor activities.
• Manual measurements can cause small size variations, so accurate measuring is essential before ordering.

Specifications

Our Verdict

The ShadeMart 18' x 20' green rectangle shade sail is a solid value for anyone seeking breathable, UV-blocking coverage that stands up to wind and sun. Its durable fabric and stainless fittings make it a dependable choice for patios, pools and carports; just be aware it is not intended as a waterproof roof. For users who prioritize airflow and sun protection, this sail offers effective performance at a reasonable price.

Frequently Asked Questions

Is this shade sail waterproof?
No. The fabric is water permeable and breathable, so it does not provide a waterproof cover but prevents pooling.

Can it be attached to trees or poles?
Yes. With the proper hardware kits the D rings and webbing allow attachment to poles, trees, walls or roofs.

How much UV protection does it provide?
The woven HDPE material blocks up to 95% of harmful UV rays, helping lower temperatures under the sail.