The RotGuard™ 4x4 Series is a pre-sized, self-adhesive wood post wrap engineered to protect 4x4 fence posts, deck posts, mailbox posts, and structural wood posts from ground-line rot.
Designed to fit square or round posts up to 4.125”, this 16-inch wrap delivers targeted soil-line protection where moisture exposure and fungal decay most commonly occur.
Ships next business day from Pennsylvania (U.S.) or Ontario (Canada).
Apply before installation to extend post life and reduce costly post replacement.
Product Overview
Wood posts rarely fail above grade. They fail at the soil line, the critical zone where moisture, oxygen, and soil organisms combine to create decay.
Even pressure-treated lumber can deteriorate over time when exposed to constant ground moisture.
RotGuard™ forms a durable waterproof barrier at the critical soil-line zone, helping reduce moisture intrusion and fungal decay at the most common post failure point.
RotGuard™ wraps are 16 inches long, approximately 2 inches longer than many traditional rot barriers, providing additional coverage above and below the critical ground-line zone where posts most commonly fail.
Key Features
✔ Pre-Sized for 4x4 Posts
Fits square or round posts up to 4.125”.
✔ Self-Adhesive Installation
No torch. No heat gun. No open flame. Peel, wrap, overlap, and press.
✔ Dual-Layer Protection
High-strength polyethylene outer layer with water-resistant adhesive membrane backing.
✔ 16-Inch Coverage Length
Designed to protect the most critical ground-contact zone.
✔ Will Not Melt in Heat
Stable in hot trailers and work trucks.
✔ Made in USA
✔ Backed by a 25-Year Limited Warranty
When installed on pressure-treated lumber or heartwood cedar.
Ideal Applications
Fence posts
Gate posts
Deck posts
Mailbox posts
Pergola posts
Pole barn framing
How RotGuard™ Works
The Science Behind RotGuard™
RotGuard™ is manufactured using SBS-modified bitumen, a high-performance waterproofing compound used in commercial roofing systems, bridges, and structural membranes where flexibility and adhesion are critical.
SBS stands for Styrene-Butadiene-Styrene, an engineered elastomer that enhances traditional bitumen with rubber-like flexibility and cold-bonding performance.
Unlike heat-applied tar-based sleeves that can cool, harden, and pull away from the wood over time, RotGuard™ remains flexible and self-sealing. Its cold-bond adhesive membrane conforms to the wood surface and embeds into the grain, helping maintain long-term contact at the ground line.
This flexible, polymer-modified system allows RotGuard™ to move with natural wood expansion and contraction while maintaining a continuous moisture barrier.
That’s the difference between a surface coating and a polymer-engineered ground-line protection system.
Complete post protection
For maximum longevity, protect all critical zones of the post:
• Shield the exposed transition zone with PostGuard™
• Protect end grain with CapClaw™
• Maintain long-term appearance with Expert Professional Wood Care
FAQ
How long does RotGuard™ 4x4 Series last?
When installed correctly on pressure-treated lumber or heartwood cedar, RotGuard™ is backed by a 25-year limited warranty against ground-line rot. Performance may vary depending on soil conditions and overall maintenance.
Do I need a torch to install RotGuard™?
No. RotGuard™ uses a self-adhesive membrane. No heat or special tools are required.
Can RotGuard™ be used on posts already in the ground?
No. It must be applied before installation, while the post is out of the ground.
Why doesn’t RotGuard™ cover the bottom of the post?
Rot occurs where oxygen and moisture combine, typically at the soil line. Below deeper burial zones, oxygen levels are too low to sustain decay.
RotGuard™ is designed for installation on wood posts before ground placement. Proper installation according to guidelines is required for warranty coverage. Performance may vary depending on soil conditions, drainage, climate, and overall post-maintenance. For full warranty terms and safety information, please refer to the Warranty and SDS documentation.
RotGuard™ is not classified as a hazardous material under OSHA HazCom standards. See SDS for details.
The RotGuard™ 4x4 Series is a pre-sized, self-adhesive wood post wrap engineered to protect 4x4 fence posts, deck posts, mailbox posts, and structural wood posts from ground-line rot.
Designed to fit square or round posts up to 4.125”, this 16-inch wrap delivers targeted soil-line protection where moisture exposure and fungal decay most commonly occur.
Ships next business day from Pennsylvania (U.S.) or Ontario (Canada).
Apply before installation to extend post life and reduce costly post replacement.
Product Overview
Wood posts rarely fail above grade. They fail at the soil line, the critical zone where moisture, oxygen, and soil organisms combine to create decay.
Even pressure-treated lumber can deteriorate over time when exposed to constant ground moisture.
RotGuard™ forms a durable waterproof barrier at the critical soil-line zone, helping reduce moisture intrusion and fungal decay at the most common post failure point.
RotGuard™ wraps are 16 inches long, approximately 2 inches longer than many traditional rot barriers, providing additional coverage above and below the critical ground-line zone where posts most commonly fail.
Key Features
✔ Pre-Sized for 4x4 Posts
Fits square or round posts up to 4.125”.
✔ Self-Adhesive Installation
No torch. No heat gun. No open flame. Peel, wrap, overlap, and press.
✔ Dual-Layer Protection
High-strength polyethylene outer layer with water-resistant adhesive membrane backing.
✔ 16-Inch Coverage Length
Designed to protect the most critical ground-contact zone.
✔ Will Not Melt in Heat
Stable in hot trailers and work trucks.
✔ Made in USA
✔ Backed by a 25-Year Limited Warranty
When installed on pressure-treated lumber or heartwood cedar.
Ideal Applications
Fence posts
Gate posts
Deck posts
Mailbox posts
Pergola posts
Pole barn framing
How RotGuard™ Works
The Science Behind RotGuard™
RotGuard™ is manufactured using SBS-modified bitumen, a high-performance waterproofing compound used in commercial roofing systems, bridges, and structural membranes where flexibility and adhesion are critical.
SBS stands for Styrene-Butadiene-Styrene, an engineered elastomer that enhances traditional bitumen with rubber-like flexibility and cold-bonding performance.
Unlike heat-applied tar-based sleeves that can cool, harden, and pull away from the wood over time, RotGuard™ remains flexible and self-sealing. Its cold-bond adhesive membrane conforms to the wood surface and embeds into the grain, helping maintain long-term contact at the ground line.
This flexible, polymer-modified system allows RotGuard™ to move with natural wood expansion and contraction while maintaining a continuous moisture barrier.
That’s the difference between a surface coating and a polymer-engineered ground-line protection system.
Complete post protection
For maximum longevity, protect all critical zones of the post:
• Shield the exposed transition zone with PostGuard™
• Protect end grain with CapClaw™
• Maintain long-term appearance with Expert Professional Wood Care
FAQ
How long does RotGuard™ 4x4 Series last?
When installed correctly on pressure-treated lumber or heartwood cedar, RotGuard™ is backed by a 25-year limited warranty against ground-line rot. Performance may vary depending on soil conditions and overall maintenance.
Do I need a torch to install RotGuard™?
No. RotGuard™ uses a self-adhesive membrane. No heat or special tools are required.
Can RotGuard™ be used on posts already in the ground?
No. It must be applied before installation, while the post is out of the ground.
Why doesn’t RotGuard™ cover the bottom of the post?
Rot occurs where oxygen and moisture combine, typically at the soil line. Below deeper burial zones, oxygen levels are too low to sustain decay.
RotGuard™ is designed for installation on wood posts before ground placement. Proper installation according to guidelines is required for warranty coverage. Performance may vary depending on soil conditions, drainage, climate, and overall post-maintenance. For full warranty terms and safety information, please refer to the Warranty and SDS documentation.
RotGuard™ is not classified as a hazardous material under OSHA HazCom standards. See SDS for details.
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