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Cellular PVC Lumber

Multipurpose, solid material with the working characteristics of wood

Imagine intricate exterior detailing that keeps its shape and never needs painting. Cellular PVC is a solid, extruded material that has the working characteristics of wood, and is used for interior trim, exterior trim, and paneling as well as windows and doors, blinds, and furniture.

PVC (polyvinyl chloride) lumber is manufactured in interior grade, exterior grade, and cellular form. Cellular PVC is created by celuka, a foaming extrusion process that creates tiny air bubbles within the shape, resulting in a density less than half that of regular PVC. The material is then cooled to form a smooth, hard skin that doesn't absorb paint or bleed. Cellular PVC has a tensile strength of 2,000 to 5,000 psi, resists deflection up to 150°F, and has a low coefficient of thermal expansion. It weighs about the same as softwood.

Cellular PVC is medium white. Boards are delivered 4' x 18' and 4' x 20', then cut up and sanded. Standard wood trim dimensions and profiles are available up to 11 1/4" x 1 3/8", and as thin as 3/8". Boards can be produced in any length, but 18' is most commonly in stock. Custom profiles can be extruded.

Cellular PVC becomes brittle below 40°F, requiring predrilling before cold weather installation, especially near edges. Residue builds up if the sander is allowed to get too hot. Cellular PVC is considered too expensive for siding, and is not structural for uses such as decking.

Quality and Durability

Cellular PVC has a tensile strength of 2,000 to 5,000 psi, resists deflection up to 150°F, and has a low coefficient of thermal expansion.


Stocked by lumber dealers. Custom profiles take about two weeks.

At approximately $3 per lineal foot, cellular PVC costs less than redwood or cedar, but more than finger-jointed pine, which ranges between $2 and $2.50 per foot.

Not Applicable

Cellular PVC has been ASTM tested for a wide range of properties. Results are available from manufacturers. Flame spread is 46, self-extinguishing when flame source is removed.

Not Applicable

Profiles can be welded like vinyl, or cut, milled and fastened like wood. A carbide blade is recommended, with milling and drilling at slower speeds to avoid excess heat. Bevel and caulk joints to allow for slight thermal expansion. Light-colored acrylic paint can be used.

Limited warranties vary from 10 to 20 years.

Cellular PVC avoids many potential problems of wood, such as rot, split, water absorption, peeling paint, and termites. It can be left unfinished, or with a color-matched permanent finish.

Disclaimer: The information on the system, product or material presented herein is provided for informational purposes only. The technical descriptions, details, requirements, and limitations expressed do not constitute an endorsement, approval, or acceptance of the subject matter by the NAHB Research Center. There are no warranties, either expressed or implied, regarding the accuracy or completeness of this information. Full reproduction, without modification, is permissible.