# Other Joints

Expansion, isolation and construction joints are created by formwork before the PCC is placed.

- Canonical URL: https://pavementinteractive.org/reference-desk/construction/placement/other-joints/
- Last updated: 2026-11-01
- Review: reviewed by licensed professional engineers on the previous Pavement Interactive site, where reviewers were not recorded by name

[Expansion](https://pavementinteractive.org/reference-desk/construction/placement/joints/), [isolation](https://pavementinteractive.org/reference-desk/construction/placement/joints/) and [construction joints](https://pavementinteractive.org/reference-desk/construction/placement/joints/) are created by formwork before the PCC is placed. Since these joints are designed to completely separate adjacent masses of PCC, they are usually made by inserting a small non-PCC piece of material such as a strip of wood.

## Construction Joints

[Construction joints](https://pavementinteractive.org/glossary/construction-joint/), sometimes called "headers" are usually made to separate successive construction activities; they do not serve any design purpose. However, with proper planning, construction joints can often be made to coincide with other planned joints, such as a transverse [contraction joint](https://pavementinteractive.org/glossary/contraction-joint/). For instance, in [slipform paving](https://pavementinteractive.org/reference-desk/construction/placement/slipform-paving/) a construction joint is made at the end of the day as a transverse piece of formwork used to shape the last slab. If enough PCC is available at the end of the day, the construction joint can be placed at a planned transverse contraction joint. Construction joint considerations include:

- *Ensure adequate PCC is available to finish the last slab of the day*. The construction joint is set before all the PCC is placed. If truck delivery is stopped to soon, the temptation may be to use the lower-quality PCC that has been pushed in front of the [screed](https://pavementinteractive.org/glossary/screed/) to fill the remaining volume. This low-quality PCC may contain little [portland cement](https://pavementinteractive.org/glossary/portland-cement/), excess water, low air and/or segregated aggregate.
- *Ensure proper consolidation*. Typically, the paver does not traverse the construction joint. Therefore, the construction joint is not consolidated by the paver vibrators and it should be manually consolidated.
- *Dowel placement should not segregate or cause air voids in the adjacent PCC*. Sometimes, [dowel bars](https://pavementinteractive.org/reference-desk/pavement-types-and-history/pavement-types/dowel-bar/) are placed after the PCC has been placed up to the header. If [dowel bars](https://pavementinteractive.org/glossary/dowel-bar/) are pounded in by hammer, the resultant vibrations may cause air pockets or segregated aggregate.