Choosing the wrong welding and assembly subcontractor only shows when it is most expensive — at handover, during a delay, or when welds have to be redone. The right one saves you the trouble and only extends deadlines when it is truly unavoidable. Here are six things to check before you sign.
1. Welder certification (EN ISO 9606)
Ask for copies of the certificates for the specific welders who will work on the project — not just a statement that the company has them. Check that the range of validity matches your welds: the process (111, 135/136, 141, SAW), the product type (plate or pipe), the thickness, the position and the base material.
2. Safety certificates and safety culture
For industrial work, and petrochemical sites in particular, SCC/VCA safety certificates and valid medical certificates are often mandatory. Ask how the contractor handles site inductions and personal protective equipment too — it tells you a lot about how seriously the company operates.
3. Posting compliance (A1)
If workers come from another EU country, they must be posted in line with the rules — with A1 certificates and notification in the country of work. Non-compliant posting is a risk for the client, not only the contractor. A reliable subcontractor handles this end-to-end and shows you how.
4. References and experience in your sector
Ask for comparable projects — by sector (bridge construction, energy, petrochemical, steel structures) and by type of work. An experienced contractor will be able to describe where they worked, at what scope and to which standards (e.g. EN 1090, execution classes EXC3/EXC4).
5. Speed of mobilization
For turnarounds and urgent needs, how fast a contractor can field a crew is decisive. Ask specifically: in how many days, with what headcount and which profiles. Vague promises are a warning sign; a clear answer points to genuinely available manpower.
6. Documentation and quality control
Proper documentation — certificates, WPS/WPQR, material and weld traceability — is not bureaucracy but insurance against defects and delays. Check whether the contractor keeps it as work proceeds and is ready to hand it over on completion.
At Save Consulting we provide certified welders and fitters with complete documentation, safety certificates and full EU posting — as a reliable subcontractor for projects across Europe.