Guide

Formwork Tubes — Application and Installation

Everything you need to know about PVC formwork tubes: how they work, which diameter to choose, step-by-step installation, and how they save money through tie rod reuse.

PVC formwork tubes are simple but essential accessories in concrete formwork construction. They serve as sleeves for tie rods (anchor bolts) that hold formwork panels together during concrete pouring. By preventing direct contact between the tie rod and wet concrete, PVC tubes enable easy stripping and — critically — allow the expensive tie rods to be reused many times over.

Available Diameters

Inner Diameter Outer Diameter Tie Rod Size Typical Use
Ø 22 mm 26 mm M16–M18 Residential construction, light formwork
Ø 26 mm 30 mm M20–M22 Standard commercial construction
Ø 30 mm 34 mm M24–M27 Heavy commercial and industrial
Ø 34 mm 38 mm M30 Industrial and infrastructure

Step-by-Step Installation

1

Drill formwork panels

Drill holes in the formwork panels matching the outer diameter of the PVC tube. Ensure holes are aligned on both panels.

2

Insert tubes

Push the PVC formwork tube through both formwork panels. The tube should extend 5–10 mm beyond each panel surface.

3

Thread the anchor bolt

Pass the tie rod (anchor bolt) through the PVC tube. The tube protects the bolt from concrete contact.

4

Tighten and pour

Tighten the formwork assembly and pour concrete. The PVC tube prevents concrete from bonding to the tie rod.

5

Strip and recover

After concrete curing, strip the formwork. The PVC tube remains in the concrete. Pull out the tie rod — it slides out easily because the PVC prevented bonding.

6

Reuse the bolt

The tie rod is clean and undamaged, ready for reuse on the next pour. This is the key cost saving.

Advantages Over Metal Alternatives

Tie rod reuse

PVC tubes prevent concrete bonding to tie rods, allowing 10–20+ reuses per rod. Metal tubes corrode and bond to concrete.

Easy stripping

Formwork strips cleanly with no concrete stuck to tie rods. Saves 30–60 minutes per panel compared to metal tubes.

Clean concrete surface

The remaining PVC tube in concrete is sealed with a plastic cap and mortar, leaving a clean, professional finish.

Lightweight

PVC tubes weigh 70–80% less than metal alternatives, reducing transport costs and making handling easier on site.

Cost effective

Although PVC tubes are single-use (they stay in the concrete), the savings from tie rod reuse and faster stripping far outweigh the tube cost.

Corrosion-free

PVC does not corrode, so the concrete around the tube hole remains undamaged. Metal tubes can create rust stains and spalling.

Frequently Asked Questions

How many times can a tie rod be reused with PVC formwork tubes?
With PVC formwork tubes, tie rods can typically be reused 10–20 times or more, as the PVC prevents concrete bonding and protects the rod surface. Without tubes, rods are often damaged after 1–3 uses.
Do the PVC tubes stay in the concrete?
Yes, the PVC tube remains in the concrete after stripping. The hole is sealed with a plastic cap and then filled with mortar or grout. The PVC is chemically inert and does not affect concrete strength or durability.
What lengths are available?
Standard lengths are 200, 250, 300, 350, 400 and 500 mm, matching common wall thicknesses. Custom lengths can be cut on site or ordered from the factory.
Can PVC formwork tubes be used in exposed concrete (fair-faced)?
Yes, PVC tubes are actually preferred for exposed concrete because they leave a clean, uniform hole that is easy to seal neatly. The result is much cleaner than with metal tubes.

Order Formwork Tubes

All diameters and lengths in stock. Competitive pricing direct from the manufacturer.