Rigid polyvinyl chloride (PVC) is also known as unplasticised (UPVC, PVC-U), because it does not contain plasticiser. As an amorphous plastic it is naturally transparent, but most often pigmented with colour. It is quite brittle with very poor temperature resistance in its pure state. Therefore, it is most commonly mixed with stabilisers to improve heat resistance for processing and use. Chlorinated PVC (CPVC, PVC-C) has a higher proportion of chlorine, which makes it less brittle.

Around half of all PVC produced goes into building products. For example, window frames, of which around half are made with PVC, with the remainder split between wood and aluminium. It is also used to make cladding (siding), pipes, gutters and drainage. These type of extruded products require only a small amount of stabiliser (<5%). UPVC extrudes very well, because it is remains relatively viscous. This makes it more difficult to produce as large injection mouldings, because the material requires a lot of force to flow the length of the die cavity. Impact modified PVC is created by blending pure PVC with toughening agents. For example, polystyrene (PS), polymethyl methacrylate (PMMA), acrylic, or polyurethane (PUR), are blended with PVC at 5-20% to enhance toughness. Impact modified PVC is used in construction products, such as doors and window frames, to reduce vulnerability to cracking, especially at low temperatures. Toughness is increased at the expense of tensile strength. High density polyethylene (HDPE, PE-HD) offers an alternative in some pipe applications, such as underground and flexible systems. Concrete and clay are also used as alternatives to PVC. All three are superior in terms of sustainability, but may not be practical for all applications and often work out to be more expensive. Zinc and zinc-coated steel (galvanised) are used in gutter and drainage. In this case, the environmental impact of PVC may be lower due to the higher density and environmental impacts of zinc production. However, zinc will outlast PVC in exterior applications, and can be recycled over and over without any loss of quality. PVC is used in packaging, such as pharmaceutical, food, water and detergent bottles. Both as a film and moulded plastic it has good barrier properties to oxygen and flavour combined with high levels of transparency. Plasticisers and fillers are added to enhance these properties. It has excellent thermoforming properties, and is cost-effective in trays, inserts, clamshells and blister packs. In the past, it was used in blow moulded drinks bottles and pharmaceutical packaging. However, due to the health concerns of PVC it is being phased out of food contact applications. Polypropylene (PP), PE and polyethylene terephthalate (PET), polyester, are widely accepted alternatives. Foamed PVC sheets are used for retail, signage, exhibitions and displays. Commonly referred to as Foamex and PVC foamboard (also Foamalite, Forex, Palight and Palfoam), it is based on a blend of PVC and polyurea. It is a low cost, lightweight, general purpose material available in a range of colours and is easy to cut and drill. It has a flat, non-porous surface that is suitable for digital flatbed printing - direct to material (DTM). Alternative materials for the same types of application include aluminium composite panels and engineered wood. Plastic alternatives include corrugated polypropylene (PP) and polymethyl methacrylate (PMMA) acrylic.