Why pre-plaster matters

Lock-up sits between frame and fixing. By this stage:
– Roof is on, windows installed, external walls sheeted
– Plumbing rough-in is complete (pipes in walls, water service connected)
– Electrical rough-in is complete (cabling pulled, GPO and switch boxes set)
– Insulation is installed
– Sarking and roof flashing are in place

What’s missing: plasterboard. Once the plaster goes up, all of the above is hidden.

A defect in plumbing rough-in becomes wet plaster. A miss in waterproofing becomes mould in 18 months. An electrical fault becomes a switchboard call-out and a chase-out repair.

Lock-up is the cheap repair window for everything inside the wall cavity.

What we check at lock-up

A thorough lock-up / pre-plaster inspection covers:

• External weatherproofing — sarking continuous and lapped, flashings to windows and doors, no gaps where water could enter
• Roof flashings — chimneys, vents, valley gutters, ridge capping (where accessible)
• Insulation — type matches plan (R-value), correctly installed in walls and ceiling
• Electrical rough-in — cable runs in correct positions, GPOs at correct heights, no damaged sheathing, lights set out per plan
• Plumbing rough-in — pipe locations match bathroom/kitchen plans, hot/cold not crossed, taps and outlets in correct positions
• Waterproofing readiness — wet-area substrate, no gaps in framing where waterproofing would fail
• Window and door installation — sealed externally, flashed correctly, plumb and square
• Wall and roof bracing — confirmed permanent (temporary bracing removed where designed to be)
• Drainage — downpipes connected, stormwater rough-in
• Penetrations — every roof and wall penetration sealed

Common defects we find at lock-up

Across hundreds of pre-plaster inspections in Melbourne’s west:

• Missing sarking laps — water can drive in behind the cladding
• Damaged sarking from trades — plumbers and sparkies cutting through without retape
• Crossed plumbing — hot supply on the cold side
• GPOs set out wrong height — too low for kitchen benches, too high in kids’ rooms
• Insulation missing in difficult-to-reach voids — over recessed lights, behind windows
• Window flashings improperly installed — head flashing missing, jamb flashings reversed
• Penetrations un-sealed — vermin and weather entry points

Your contract right to inspect

Most domestic building contracts in Victoria recognise the buyer’s right to attend stage inspections, including lock-up. Independent inspection at this stage is not a courtesy — it’s contract due diligence.

The VBA’s Practice Standard requires builders to remedy defects identified at any inspection stage. A documented defect at lock-up is binding.

Frequently asked questions

When is lock-up reached?

After the roof is on, windows and external doors fitted, and the home is “weatherproofed” — but before plasterboard is hung. Your builder will notify you when this stage is achieved. Book the inspection within 2-3 days of that notification.

How long does the inspection take?

1.5-2 hours on site for a standard 4-bedroom home. Same-day photo-rich written report.

Will the builder fix defects found at lock-up?

Yes. Defects identified at this stage are clearly documentable (photos, location, NCC clause) and the builder is contractually required to rectify before plaster proceeds.

Should I attend?

Recommended — at least for the wrap-up. You’ll see the home with its bones still exposed; once plaster is on, you’ll never see it again.

Book a lock-up inspection

New Home Stage Inspections — Melbourne West — VBA-registered builder, four-stage inspections, same-day reports.

Related guides:
– The 5 Stages of a New Home Build
– Frame Stage Inspection — What Your Inspector Checks
– Pre-Slab Inspection — What’s Checked Before the Pour
– PCI Checklist — Practical Completion Handover

Call Michael direct on 0412 014 216 to book.