An awning is an external, retractable shade made of fabric that swings out in front of a window or over a terrace on hinged arms. It belongs to the family of external movable solar shading, which makes it something quite different in building physics terms from a blind hung behind the glass.
Why external shading works so much better
Shading on the outside intercepts solar radiation before it passes through the glass. What the fabric absorbs is largely re-radiated back to the outside air. Internal blinds cannot do that: by then the heat is already inside the room. External shading is therefore the most effective single measure against summer overheating — more effective than solar control glass, because you can retract it in winter and let the solar gain in when you want it.
Types
- Folding arm awning — a wide fabric on articulated arms over a terrace; gives shade on the terrace rather than precise shading of the window
- Drop arm awning — the fabric tilts outwards like a small canopy; often used over dormers and upper floor windows
- Traditional hooded or shop awning — the classic half round form with closed sides, common on shopfronts and older buildings
- Vertical screen — a fabric running taut in side guides directly in front of the glass; the best answer where there is no room to project, and the least wind sensitive of the family
Practical points
- Wind resistance. Retractable shading is wind sensitive. Manufacturers state a wind resistance class to the European product standard for external blinds (EN 13561); a higher class means a higher permissible wind load. On a tall or exposed facade a wind sensor that retracts the awning automatically is close to essential
- Fixing. The arms impose a substantial bending moment on the wall. Always fix into structural masonry or the frame — never into the outer leaf of a cavity wall alone, into insulation or into brick slips. On an externally insulated wall use thermally broken standoff brackets
- Consent. On a listed building, in a conservation area, on a shopfront or under a leaseholders’ agreement there are often rules about colour, form and projection. Check before ordering
- Fabric. Acrylic cloth is colourfast and breathable; PVC coated glass fibre screen fabric is dimensionally stable and dirt resistant. Never leave a wet fabric rolled up for long periods
- Cost. For an awning or drop arm unit over a typical window, expect roughly 700 to 2,500 euro including fitting, depending on width, fabric and motorisation
Related terms
- Solar shading
- Canopy
- Overheating
- Venetian blind
- Facade
- Window frame
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