Here at Exterior Plas, our factory is very much at the heart of the business and the keystone to our entire operation and the services we offer our clients. Our manufacturing spaces total around 15000 sq feet and filled with our state of the art CNC machinery in order to maintain levels of accuracy, as well as improving productivity ensuring a quality product with a fast turnaround for our customers. Exterior Plas has been fabricating REHAU products for over 25 years – and since its launch in 1988 has remained one of the largest manufacturers of windows and doors using the ‘Calibre’ profile, alongside the TOTAL70 suite, and the Rehau ‘Rauferno’ fire rated products for which we spear-headed the Research and Development over 20 years ago.


Our vast storage facilities, cutting edge machinery, and automated systems mean we have the capabilities when called upon to offer a quick turn around on a varied amount of quality products. This undoubtedly gives us the edge over many of our competitors who often rely on a third party for pre-fabricated windows and doors. A further factory is given over to our warehouse and cutting area. Here we stock and cut all of our ancillary items. This depot is situated adjacent to our recycling areas, and is our loading zone for our teams of installers, and the hub of activity throughout the day. Prior to investing heavily in the CNC machinery all of the window and door frames and sashes were cut by hand showing that our workforce has massive manufacturing experience on top of the advantage that the new machinery provides.

Cutting and Welding

From survey and pricing to final beading and packing, the entire platform is accurate to within 1mm allowing a perfectly created product coupled with the most attractive costings. The enormous cutting centre that is so important to the machining process, will cut profile and route holes for vents and locking mechanisms as well as providing spot marks for accurate hanging of doors and window sashes, preventing any mis-alignment that could cause future quality control issues. The Welders will take the cut profile, heat the ends of the plastic to within one degree of optimum operating temperature and push the two sections together to create an unbreakable joint. The cutting centre will provide an extra 2mm of plastic on top of what is required so that when the welder pushes the soft plastic together, the frame or sash will then be at the correct size post weld. The strength of these joins is regularly tested to ensure that products with faulty joints aren’t being installed.

Corner Cleaning and Beading

The corner cleaner is the last major CNC machine involved in production. The design of the profile is programmed in the the controlling software and the cutting blade will clean all of the excess weld from the item in production, not only to improve appearance of the internal and external faces, it also cleans inside the rebate area to ensure the glass doesn’t clash with the plastic causing failures and blown units during installation or expansion in hot or cold weather. Beading is an important part of our products providing a safe retention of glazing and panel, and a perfectly fitting bead is essential to clip in to the frame profile. Bead that is too short will show a gap and a loss of U Value rating, and a bead too long will cause damage when fitting. We have invested in a CNC measuring and cutting centre to provide the perfect length of bead every time. Our BSi accreditation ensures our manufacturing capabilities, testing, quality control and document control are inspected and verified bi-annually, so we always offer a high quality and assured service. We believe this gives our customer peace of mind that their project is always in safe hands.

Environmental Responsibility

As you can imagine with a busy factory and high workflow, offcuts from the bars of profile and old frames that have removed from site during our installations are constantly present. Rather than put this into landfill, we ensure that we recycle as much as possible to be ground down into pellets and reused, providing a longer lifetime for the material. We also try to recycle as much glass as possible through a local glass recycling company.