12 Felt Lap Vents for Loft Ventilation
Product description
This set of loft vents brings straightforward roof ventilation for moisture control, helping reduce condensation in attic spaces and improve airflow under tiles. These felt lap vents for condensation come as a pack of 12 and are useful when you need to increase ventilation behind roof felt to keep a loft drier during colder months.
Key Points
Each vent has an arched form that resists compression and allows more air to pass through the roof underlay. The raised shape keeps the channel open even where the felt joints are compressed, so airflow remains consistent across the run. This can help extract steam after bathing and reduce winter damp in the loft.
Installation is simple and quick. The vents push between felt laps and sit under the battens, creating a path for outside air to enter the loft void. They suit common joist centres, which means they fit most domestic roofs without special trimming. Consider that they are intended to aid ventilation and may not replace the need for professional roof repairs where there is structural damage.
Technical Specifications
- Name: 4BAOHUI 12 x Felt Lap Vents
- Quantity: 12 units per pack
- Dimensions: 203 mm length x 280 mm width x 19 mm height
- Free air flow per unit: 3000 mm²
- Compatible joist centres: 400 mm to 600 mm
Usage Recommendations
Fit the vents by pushing them into the laps of the roofing underlay so that each unit spans the gap under the battens. For best effect, space them evenly along the eaves and ridge runs to promote cross ventilation. If the roof has narrow batten centres or irregular batten spacing, check alignment before fixing to ensure the vents sit flat and maintain the air channel.
The vents are practical where condensation forms due to poor circulation, particularly in older roofs with limited breathable membranes. They are not a waterproof membrane and should be used in combination with correct roofing practices and appropriate ventilation strategy. The arched design increases resilience against pressure from tiles and battens, but note that heavy loading or poor installation can affect performance. 😊
These lap vents bring an economical way to increase airflow under roofing felt and can be added incrementally as ventilation needs become apparent. They are light to handle and do not require specialised tools for basic fitting, although a roof-safe working method is essential. 🛠️