These extra-strong DIY concrete forms are made of multiple layers of high quality fiber, spiral wound and laminated with a heavy-duty adhesive. A special coating resists moisture and facilitates even curing.
Builder’s tubes are designed for below-grade use, but may be poured to three feet above the ground line. They are not designed to be stripped. No bracing is needed unless used two feet above ground line. Even then, bracing requirements are minimal.
To view more info about how these form tubes are used please click here to view the post information page.
Use the following chart to figure out how much concrete you will need to fill the form tube upon pergola installation.