Outdoor Ventilation Cowl — Wind-Proof, Rainproof & Insect-Proof Cowls for Every Duct
An outdoor ventilation cowl is the critical last point in any exhaust or fresh air duct system. Without the right cowl, your duct opening is exposed to rain, insects, birds, and wind-driven debris — reducing efficiency and risking system damage. Astberg's range of outdoor cowls delivers professional-grade protection for residential, commercial, and industrial ventilation setups across India.
What Is a Ventilation Cowl and Why Do You Need One?
A cowl (also called a vent cap, duct cowl, or pipe cowl) is a protective cover fitted to the external outlet of a duct pipe. It allows air to flow freely in or out while blocking rain, wind, birds, and insects from entering the ductwork.
Key reasons to fit an outdoor cowl:
- Prevents rainwater from flooding your duct and fan
- Blocks insects, birds, and debris from nesting inside
- Reduces wind pressure that can reverse airflow
- Extends the life of your inline fan or exhaust system
- Maintains consistent ventilation performance year-round
Whether you're installing a bathroom exhaust, kitchen hood duct, HRV/ERV system, or commercial air handling unit — a properly sized, weather-resistant cowl is non-negotiable.
Astberg Cowl Range — Steel & PVC Outdoor Cowls
Astberg offers one of India's most complete selections of outdoor ventilation cowls, available in multiple sizes, materials, and finishes:
Steel Cowl (SS304 / Powder Coated Grey)
Built from SUS 304 stainless steel or powder-coated mild steel, Astberg's steel cowls are ideal for long-term outdoor use. The grid-layout inclined louvre design with aluminium alloy mesh provides outstanding wind-proofing, rain resistance, and insect protection. Available in 100mm (4"), 150mm (6"), 200mm (8"), and 250mm (10") diameters.
PVC Cowl (Long Pipe / Standard)
Astberg's PVC cowls are lightweight, corrosion-resistant, and UV-stabilised for extended outdoor exposure. Perfect for smaller residential or bathroom duct outlets. Wind-proof and insect-proof design in a clean white finish.
How to Choose the Right Cowl Size
Selecting the correct cowl is straightforward when you match it to your duct pipe diameter:
- 100mm / 4" Cowl — Standard bathroom exhaust, small kitchen fans
- 150mm / 6" Cowl — Medium inline fans, HRV/ERV connections
- 200mm / 8" Cowl — High-capacity exhaust systems, commercial kitchens
- 250mm / 10" Cowl — Industrial ducting, large air handling units
Always measure the outer diameter (OD) of your duct pipe before ordering. Astberg cowls are designed as socket-fit or push-fit for quick, tool-free installation.
Installation Guide for Outdoor Cowl
- Identify the external duct outlet on your wall or roof surface.
- Select the cowl size matching your duct pipe diameter.
- Clean and dry the pipe end for a secure fit.
- Push or slide the cowl onto the pipe end — most Astberg cowls are push-fit (no tools needed).
- Seal around the flange with weatherproof sealant for long-term outdoor exposure.
- Check louvre direction — louvres should face downward to maximise rain rejection.
Why Buy Your Cowl from Astberg Ventilation?
- ✅ Complete range of sizes from 100mm to 250mm
- ✅ Premium SUS304 stainless steel and UV-resistant PVC options
- ✅ Bird mesh / insect mesh included on key models
- ✅ Bright polished or powder-coated finishes for all-weather durability
- ✅ Free shipping across India on orders over ₹5,000
- ✅ 30-day return policy for hassle-free purchase
- ✅ Based in Ludhiana, Punjab — fast pan-India delivery
Frequently Asked Questions About Ventilation Cowls
Q: What is the difference between a cowl and a vent cap?
A: They refer to the same product — a cover fitted to the end of a duct pipe to prevent rain and debris ingress while allowing airflow. "Cowl" and "vent cap" are used interchangeably in ventilation.
Q: Do I need a cowl with bird mesh?
A: If your outlet is exposed or at roof level, a cowl with bird and insect mesh is strongly recommended. It prevents birds from nesting inside ducts, which can block airflow and damage fans.
Q: Can I use a PVC cowl outdoors?
A: Yes, Astberg PVC cowls are UV-stabilised for outdoor use. However, for high-exposure commercial or industrial locations, SS304 steel cowls offer superior longevity.
Q: What cowl size do I need for a 6" duct?
A: You need a 150mm (6") cowl to match a standard 6" (150mm) duct pipe.
Q: Is installation difficult?
A: No. Most Astberg cowls are push-fit and can be installed without specialist tools. Fixing with weatherproof sealant is recommended for permanent outdoor installations.
Q: Do Astberg cowls work with HRV and ERV systems?
A: Yes. Astberg steel and PVC cowls are compatible with all standard round duct pipe systems, including HRV (Heat Recovery Ventilation) and ERV (Energy Recovery Ventilation) units.
