Home ventilation component engineered to stop backdraughts and keep rain out while letting extractor fans vent efficiently. Perfect for homeowners who want a tidy, reliable external vent, VENTS UK External Gravity Grille. How well do durability and ease of fitting hold up in everyday installs?
⚡ At a Glance
- • Airflow Control: Gravity-operated shutter opens under extractor airflow and closes automatically to prevent backdraughts and rain ingress
- • Best for: Homeowners and installers needing a simple external vent for 100 mm ducting, bathrooms, kitchens or tumble dryer extraction
- • Not ideal for: Systems requiring duct diameters larger than 100 mm or active motorised louvre solutions
External grille measures 155 mm x 155 mm with a 100 mm diameter duct connection and three non-return gravity flap outlets. Manufactured from premium plastic and compliant with Building Regulations Approved Document F.
Stops rain, odours and vermin - with three non-return gravity flaps
Three gravity flap outlets remain closed when no extraction airflow is present, and open only when extractor airflow pushes through. Flaps therefore block wind-driven rain, odours, noise and small pests while allowing full airflow during extraction.
Reliable protection keeps external weather and unwanted intruders out of ductwork, preserving indoor air quality and preventing water ingress.
Quick, straightforward installation - with a 100 mm push-fit connection
Push-fit duct and fittings connect directly to the 100 mm diameter outlet, allowing a sealed joint with optional mastic, poly cement or tape. No complex fixings are required for a standard external wall run.
Fast fitting makes the grille suitable for retrofit or new installations, reducing time on site and simplifying the work for tradespeople.
Low-maintenance outdoor performance - with premium quality plastic construction
Moulded from premium plastic and finished in black for outdoor durability, the grille is designed to withstand repeated shutter movement and exposure to the elements. Materials resist corrosion and typical outdoor wear.
Sturdy construction gives long service life with minimal upkeep, matching user reports of a well-made, reliable product.
✨ The 4 Key Reasons for VENTS UK External Gravity Grille
- Three non-return flaps - Prevents backdraughts and odours when extractor is inactive
- 100 mm push-fit connection - Fits standard ducts quickly, reducing installation time dramatically
- Weatherproof black finish - Keeps out rain and resists outdoor weathering over time
- Building Regulations compliance - Suitable for projects requiring Approved Document F conformity
📋 Technical Details at a Glance
- Category: Home ventilation external grille
- Duct connection: 100 mm (4 inch) diameter
- External dimensions: 155 mm x 155 mm
- Material: Premium quality plastic
- Colour / Finish: Black, weatherproof finish
❓ Frequently Asked Questions
Q: Is the grille compatible with 100 mm ducting?
A: Yes. The grille has a 4 inch / 100 mm diameter duct connection designed for standard 100 mm ducts.
Q: Will the grille stop rain and pests entering when the fan is off?
A: Yes. Three non-return gravity flaps close automatically when airflow stops, helping to prevent rain, odours, noise and vermin entering the duct.
Q: How simple is installation for a retrofit?
A: Push-fit duct and fittings enable straightforward installation, and optional sealing with mastic, poly cement or tape can be applied for an airtight finish. User reviews note easy fitting and reliable performance.
🏆 Our Verdict
Suitable for homeowners and installers who need a compact, reliable external vent for 100 mm duct systems. The key selling point is the gravity-operated three-flap design, which combines effective airflow control with weather and vermin protection. Overall, the grille offers durable, low-maintenance performance and strong long-term value for standard external ventilation runs.
