Key takeaways
- Invite subcontractor foremen as guests to a coordination group per project.
- Keep internal GC discussions in a separate group subcontractors can't see.
- Post the weekly look-ahead and pin it; trades confirm with a reply.
- Hand-offs between trades are confirmed with photos of the area.
- Remove each trade's guests at closeout so access ends with the contract.
On most building projects, the general contractor’s own team is a minority on site. Electricians, plumbers, drywallers, HVAC and specialty trades each have their own foreman, crews and priorities. Coordination meetings set the plan, but the plan changes daily, and those changes travel through phone calls and personal WhatsApp groups that nobody controls.
Why subcontractor coordination breaks down without a system
Coordination failures on site follow predictable lines:
- Changes don’t reach every trade. The drywall crew shows up on a floor the electricians haven’t finished.
- Personal groups mix projects. A foreman working on three of your jobs gets messages for all of them in one thread.
- Internal talk leaks. In an ad-hoc group, nobody is sure who’s reading. Cost or performance comments reach the wrong person.
- Access never ends. A trade finishes its scope but stays in the group for the rest of the project, or the next one.
The general case for structured contractor channels is in coordinating contractors in one secure chat.
The workflow in C Chat
- Set up two groups per project: “[Project] – Internal” for the GC team and “[Project] – Coordination” for the GC plus subcontractor foremen.
- Invite each foreman to the coordination group with guest access, by link, QR, WhatsApp, SMS or email.
- Post the weekly look-ahead every Friday and pin it. Each trade replies to confirm their dates.
- Daily changes go into the coordination group as they happen: sequence shifts, crane availability, inspections.
- Hand-offs: when a trade finishes an area, its foreman posts photos and “Area ready for [next trade]”. The next trade confirms.
- Closeout: when a trade’s scope ends, remove its guests from the group.
Before inviting outside companies, review the guide on inviting guests and contractors safely.
Group setup and message template
Pin these two templates in the coordination group:
Look-ahead – week of [date] Mon: [area] – [trade] · [area] – [trade] Tue: … Inspections: [type – day – area] Deliveries: [material – day – gate] Site rules this week: [crane, road closures, quiet hours]
Hand-off – [area] From: [trade] · To: [trade] Status: complete / partial (what’s left) Photos attached · Notes: [penetrations, protection, damage]
Hand-off photos are evidence when damage is disputed between trades. The internal daily log, covered in construction daily logs with site photos, can reference hand-offs rather than repeat them.
Roles, oversight and records
| Role | Group | Responsibility |
|---|---|---|
| Project manager (admin) | Both | Invites and removes guests, owns the look-ahead |
| Superintendent | Both | Daily changes, hand-off confirmation |
| Subcontractor foreman (guest) | Coordination only | Confirms dates, posts hand-offs and issues |
| Owner’s rep (guest, optional) | Separate client group | Progress updates |
Messages are encrypted in transit with TLS and at rest with AES-256 with a key unique to your organization. Owners and admins can audit and export group conversations, which helps with delay claims and back-charges. Direct messages between people stay private, so decisions that matter should be confirmed in the group.
Safety hazards that affect every trade go out through the alert workflow in job site safety alerts, not as a buried message in the coordination thread.
Common mistakes to avoid
- Mixing internal and coordination talk. Keep a separate internal group. Subcontractors should never see cost or performance comments.
- Inviting whole crews. Invite foremen; they relay to their crews. It keeps the group readable and within the 50-member limit.
- Unpinned look-aheads. Pin the current plan and unpin the old one.
- Forgetting closeout. Remove each trade when its scope is done.
The same guest pattern works outside construction: facility teams use it for vendor coordination, cleaning companies for crews at client sites, and care homes for outside providers, as described on the senior care page. For the industry overview, see team chat for construction companies.
Getting started
On your next project, create the internal and coordination groups at getcchat.com/c, invite the first two trades as guests and post the look-ahead on Friday. C Chat is free for now; see pricing for team limits.
Frequently asked questions
How do general contractors communicate with subcontractors?
Usually through a mix of meetings, phone calls, email and personal text groups. A dedicated coordination group per project, where each trade's foreman is a guest, puts schedule changes, site rules and hand-offs in one place everyone can see and search.
Will subcontractors see our other projects?
No. Guests only see the groups they were invited to. Your other project groups, internal discussions and direct messages are not visible to them.
Do subcontractors need a paid account?
No. C Chat is free for now. Subcontractors sign up with their phone number or email and join through your invitation. Guests count toward your team's member limit of 50 on the free plan.
Can a subcontractor share drawings or submittals in the group?
Yes, files up to 25 MB can be shared, which covers most PDFs and marked-up photos. Large drawing sets should stay in your document management system, with a link or reference posted in the group.