Screen Door

A screen door can refer to a hinged storm door (cold climates) or hinged screen door (warm climates) covering an exterior door; or a screened sliding door used with sliding glass doors. In any case, the screen door incorporates screen mesh to block flying insects or airborne debris such as seeds or leaves from entering, and pets and small children from exiting interior spaces, while allowing for air, light, and views. For the purposes of this article, a screen door will be considered to be the latter type used with a sliding glass door.

The first screen doors were made using cheesecloth. After the civil war, wire cloth was coated with paint and sold for window screens.

Aluminium sliding screen doors are generally constructed by two methods: rollformed or extruded. In both cases the rectangular rollformed or extruded shapes are joined together into a door frame using metal corners or screws.

The first are rollformed from thin aluminium sheets into a rectangular shaped door frame which incorporates a screen channel to hold the window screen material.

Rollformed aluminum sliding screen doors are the least expensive to produce because they can be manufactured from thin aluminum sheet formed into a relatively strong rectangular shape.

Rollformed screen doors have mitered corners into which a steel or aluminum alloy corner is forced using a friction fit. If a steel corner is used, the rollformed sections are often pierced or staked into the corners, to help secure the corners together. If aluminum alloy corners are used, the corner relies on its friction fit alone to hold the door frame together.

The weakest point of a rollformed sliding screen door is the corner. After repeated opening and closing, stresses will cause the rollformed shape to loosen in the area of the corner. The door will then stick and jam and typically will require replacement rather than repair

The second are extruded aluminum shapes, with aluminum frames made from thicker aluminum than rollformed doors. This makes an extruded aluminum door much stronger but also more expensive. Extruded aluminum screen door frames can be mitered and joined with aluminum alloy corners or can be notched out and joined together with screws that fit in screw holes made as part of the extrusion process.

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Wikipedia