Useful tip: folding patio doors and wind resistance

When buying folding patio doors, you’ll no doubt want the peace of mind that even when it’s really windy your doors will keep the gales out and stay intact.

Fear not, folding patio doors are tested for their resistance to a wind load and rated accordingly. The test involves gradually increasing the air pressure to simulate wind force and then measuring both the extent to which the folding patio doors bend (deflection) and the point at which the draughts start to get through (maximum test pressure).

Performance levels for deflection are grouped into classes A, B and C, where A is the worst and C is the best. Performance for maximum test pressure is grouped into five classes, where class one is the lowest performance and class five is the best.

A class five window or door, therefore, can withstand 2000Pa of pressure, which is the equivalent to 127mph winds.

If you’re interested in finding out more about Reynaers Windows and Doors, please click here to submit your details, so that we can put you in touch with one of our dealers. Alternatively, please call 0121 421 9707 or email

Folding Patio Doors Garden View

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