Roof expansion joints and waterproofing continuity
A roof expansion joint must connect movement accommodation with continuous waterproofing. The exposed profile and the concealed weatherproofing detail should be reviewed together.

Selection considerations
Identify the roof build-up, structural opening, insulation and drainage direction. Check whether the system interfaces with the specified membrane and how changes of level are handled. Do not leave corner transitions to be resolved after straight profiles are installed.
Keep movement and water-control requirements explicit in the enquiry. Review upstands, terminations and access for inspection. Catalogue geometry can support shortlisting, but the final assembly needs a documented interface with the actual roof materials. Include these connection details in the installation scope and handover record.
Before you specify or order
- Draw the complete roof build-up
- Coordinate membrane interfaces
- Plan corners and inspection access
Relevant BULDX catalogue examples
These records illustrate the product types discussed. Compare the full specifications before selecting; listing here does not establish project suitability or make the items interchangeable.

ROOF JOINT SERIES · Product geometry from the catalogue; a family illustration may be shared by variants. Consult the selected technical documents for dimensions and the approved fixing detail.| Product and code | Selected catalogue fields |
|---|---|
ROOF JOINT SERIESRoof & Parapet JointsRoof Joints |
|
ZEJ-KU1Water-Insulated Floor JointWatertight Expansion Joints |
|
Common question
Is a metal cover enough to make a roof joint watertight?
No. Waterproofing depends on the complete assembly and its connections to the roof system.
References and scope
Product fields are from the BULDX catalogue. Confirm the current selected drawing, supporting performance documents and approved project detail before ordering. External references, where listed, provide background guidance and do not certify these products.