Quality with FransWhat CAS is
CAS is a single set of pre-qualification questions developed by Build UK, so subcontractors and suppliers do not fill in a different questionnaire for every main contractor. It covers areas such as health and safety, quality, environment, building safety and information security. Companies are certified once a year by one of seven Recognised Assessment Bodies (for example Achilles, Constructionline, CHAS, SMAS, CQMS, SCCS and Compliance Chain), at desktop or site-audit level.
Version 5 vs Version 6
| Topic | Before (V5) | Now (V6, from 1 Nov 2026) |
|---|---|---|
| Competence questions | Inside the Building Safety section | Moved to the Quality section, completed by all suppliers |
| Building Safety section | Opt in | Opt out allowed, with a statement that you do no building work regulated by the Building Regulations (for example scaffolding and most temporary works) |
| Person responsible for quality | Not mandatory for every company | Mandatory: a dedicated person responsible for quality |
| Fraud prevention, drugs and alcohol policy | Not mandatory for every company | Mandatory for all companies |
| Information security | Cyber Essentials Plus or ISO 27001 could give an exemption | CHAS reports that only ISO 27001 now gives the exemption (not yet confirmed by Build UK's own summary) |
| Guidance | Standard guidance | Enhanced guidance to the question set |
Sources agree on the competence move, the opt-out and the new mandatory questions. Only one source mentions the information security change so far, so check it with your assessment body.
Why this matters for QA/QC
Two of the changes land on the quality team's desk. First, every supplier now has to show a named person responsible for quality. For a small subcontractor that often means the site manager wearing a second hat, so the assessor will want to see that the role is real: a name in the quality procedure, a job description and some evidence it is being done, such as inspection records or a closed NCR.
Second, competence is now a quality question for everyone, not only for firms doing higher-risk building work. Expect to show how you know your people can do the job: training and card records, assessments, supervision and how you check a new starter before they work unsupervised. On site, this is the same evidence a main contractor's QA team asks for at a subcontractor start-up meeting, so it makes sense to keep one competence register and use it for both.
Check on your site tomorrow
- Find out when your company's CAS certificate renews. V6 applies at that next certification, so plan the evidence now.
- Check your quality procedure names a person responsible for quality, and that they have a written role and recent records to show.
- Pull your competence evidence into one register: training, cards, assessments and supervision sign-offs for every trade you employ.
- Ask your subcontractors which assessment body they use and whether they are ready for V6. Their gaps can delay your pre-start approvals.
- If you are a scaffolding or temporary works firm, confirm with your assessment body how to record the Building Safety opt-out statement.
The 31-point checklist I use before every pour: bar sizes, spacing, cover and laps against the approved drawing.
Download the checklist
Sources: The Construction Index: Build UK updates Common Assessment Standard · CHAS: CAS Version 6, what the changes mean · NFRC: CAS Version 6 update · NASC: CAS changes for scaffolding contractors · Specification Online: CAS updated in line with regulatory developments · Build UK: Common Assessment Standard. Summary in my own words; your assessment body and Build UK's question set guidance apply.