ALUMINIUM WINDOW SILL

Window sill extension is a non-corrosive aluminium ledge profile suitable for EWI (external wall insulation) systems, thin coat rendering and most conditions requiring the weathering. It has been designed to either overlap or replace existing sill and protect the building facade windows and to drain rainwater. They should be tightly connected with the window frame so that during rain the water runs down the window and plaster onto the window sill, and then onto the ground, not under the window. In order for the water to drip down, the external window sill should be installed with a slope of 1-2% to the outside. It must protrude 2.5-5 cm beyond the face of the wall. Additionally, an important element of external window sills is a drip - their outer edge. It should always be profiled in a way that prevents water from seeping under the window sill. Generally speaking, the external window sill should be wider than the thickness of the insulation layer on which it is installed. The window sill must not cover the woodwork drainage holes. Sill comes 2500mm long and is made from 1.2mm thick aluminium, white powder coated on both sides to deliver a high quality durable finish and improve appearance of the buildings. Variations on any of these sills can be manufactured to custom specific requirements, and powder coated to any RAL colour. 

WINDOW SILL INSTALLATION

When installing external aluminium window sills, the following guidelines should be taken into account:

• The window sill should protrude 30-40mm beyond the finished facade.
• When cutting the sill to size, protect the edges.
• Aluminum window sills have a slight linear expansion (heating by 50 degrees Celsius causes an elongation of 0.5 mm), thanks to which window sills up to 6m long can be installed without an expansion joint.
• In order to ensure proper drainage of water from the sill surface, a 5-degree inclination should be used.
• The self-adhesive protective film should be peeled off immediately after installing the window sill.
• The gap under the sill must be filled with low-expansion polyurethane foam. It is a good idea to load the sill along its entire length right after applying the foam.
• Polyurethane foam must be applied carefully, in small portions. When too much foam is applied, it can push the sill upwards.
• Remove the protective film from the window sill and secure it with silicone.

HOW TO CUT AN ALUMINIUM SILL?

Most often, angle grinders, circular saws and jigsaws are used for this purpose. The angle grinder works well when cutting aluminum, provided that a special cutting disc is used for this material. Another handy piece of equipment suitable for cutting aluminum is a jigsaw. In this case suitable saw blades must be purchased. It is worth paying attention to whether the specification contains information about the possibility of cutting aluminum and the maximum thickness of the sheet. A circular saw is a universal tool used in various types of workshops. It can also be used for cutting aluminum, but as with an angle grinder, you should choose an aluminum blade for it. When cutting an aluminum, it is absolutely necessary to remember about personal protective equipment: glasses and gloves.

We offer one of the widest ranges of sill extensions. Extensive stock levels are held, enabling an excellent level of service, whilst also maintaining uncompromising quality. All our Aluminum window sills are produced by the aluminum pulling method from structural alloys that meet the highest quality standards. In addition to this, a specialist fabrication service is available for unique specifications requiring made to measure details. Custom cut / custom made external window sill extenders can be manufactured to your specific requirements, and powder coated to any colour from 2530 RAL colors available.

 721 WINDOW SILL EXTENSION AND OVERSILL EAVES FLASHING       

731 SILL EXTENSION AND UNDERSILL TRIM FLASHING

741 SOFFIT EAVES FLASHING SILL EXTENSION TRIM           

  751 OVERSILL O'SILL EXTENSION OVER TRIM SILL    

761 STANDARD SILL EXTENSION TRIM OVER-SILL O'SILL

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