The free area is approximately 14,133 mm2
Fan roof vents offers an attractive and long lasting method of adding ventilation to a building. Our unique lead vent registered design can be used to ventilate a roof or attach to mechanical extraction systems via flexible ducting. Leadworx fan vents offer a high quality finish preferred by many architects and builders across the UK. (These lead vents come with an optional stainless steel fly mesh).
LEADWORX TOOLS
Calculate from measurements, or estimate the angle from a photograph.
Measure the vertical rise and horizontal run between the same two points.
Use the same unit for both, such as mm or cm. Run is not the sloping roof length or automatically the full building width.
Enter your measurements to begin.
Enter measurements first.
These formats describe the same slope; they are not product size recommendations.
Use a square-on view of the roof profile, with a known horizontal reference in the same plane.
The photo box opens your camera on supported phones and tablets. On a computer, choose a photo file or drop one into the box.
Processed on your device by this tool. JPG, PNG or WebP, up to 20 MB and 24 megapixels. Export HEIC as JPG first.
Tap the photo box or choose a saved photo.
Tap four points: two on the roof slope, then two on a level reference. Drag points to adjust. Use long lines for a better estimate.
Focus the photo. Arrow keys move the marker; Shift moves 10 pixels. Enter adds a point. Select a placed point below to adjust it with the arrows. Escape returns to the free marker.
No points placed.
Mark the photo first.
The reference line corrects camera tilt, not perspective or lens distortion. A photo cannot guarantee the angle needed for manufacture.
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