A comprehensive building inspection is a highly structured process. Professional inspectors do not simply wander through a home looking for obvious flaws; they follow a rigorous, standardized methodology designed to evaluate every accessible square inch of a property. This systematic approach ensures that no structural system, safety mechanism, or environmental vulnerability is overlooked.
For buyers, owners, and contractors, understanding the exact criteria that professionals evaluate can demystify the inspection report. This article breaks down the definitive checklist that professional building inspectors utilize during a property evaluation.
Contents
1. Exterior Boundaries and Site Features
The Building Inspection begins at the outer boundaries of the property and works inward. The site surrounding a building has a direct impact on the structure’s long-term health.
Retaining Walls and Fencing
Inspectors evaluate the structural condition of retaining walls, checking for leaning, bowing, cracking, or inadequate drainage weep holes. Fences are inspected for timber rot, structural stability, and appropriate alignment along property boundaries.
Site Drainage and Grading
The slope of the ground surrounding the house is analyzed. Ideally, the ground should slope away from the foundations at a minimum gradient to prevent rainwater from pooling against walls. Inspectors look for blocked yard grates, inadequate spoon drains, and signs of soil erosion around structural footings.
2. External Building Structure and Envelope
The exterior shell of the building must be entirely weatherproof and structurally sound to protect the internal living spaces.
Wall Cladding and Masonry
Inspectors examine brickwork for structural cracking (especially cracks wider than 2mm), failing mortar joints, and signs of dampness. For timber or composite cladding, they check for secure fixings, warping, rot, and correct clearance from ground levels.
Windows, Doors, and External Trim
Every external window and door frame is checked for squareness, structural alignment, operational ease, and timber decay. Flashing details above windows are scrutinized to ensure water cannot penetrate the building envelope.
3. Roof System and Roof Cavity
The roof system is highly vulnerable to environmental degradation. Inspectors evaluate both the external surface and the internal structural framework within the ceiling space.
External Roof Covering
Inspectors analyze the condition of roof tiles, metal sheeting, or shingles. They actively look for cracked tiles, secure fixings, surface rust, and compromised ridge capping mortar. They also inspect gutters, downpipes, and flashings for blockages, rust, and correct drainage falls.
Internal Roof Space Structure
Once inside the roof cavity, the inspector examines:
- Trusses and Framing: Checking for sagging, cracked timbers, or unapproved modifications to structural framing.
- Insulation: Assessing the type, coverage, thickness, and safety clearances around downlights or electrical hardware.
- Sarking and Lining: Verifying the presence and condition of reflective foil underlays designed to repel moisture and radiant heat.
4. Internal Areas and Living Spaces
The interior inspection involves checking every room for hidden structural movement, moisture damage, and operational defects.
Walls, Ceilings, and Floors
Inspectors look for deflection or sagging in plaster ceilings, structural cracking in walls, and uneven or bouncy flooring. They use specialized spirit levels and laser levels to check if the floors have deviated from a true horizontal plane.
Wet Areas (Bathrooms, Kitchens, Laundries)
Wet areas are scrutinized intensely using moisture meters. Inspectors look for failed silicone joint seals, loose or cracked tiles, signs of leaking pipes within vanities, and adequate ventilation fans to combat high humidity.
Summary Checklist of Professional Inspection Points
The table below summarizes the key operational items checked across different locations during a professional building evaluation.
| Inspection Area | Specific Checklist Items Evaluated | Primary Detection Goal |
| Site Grounds | Driveways, retaining walls, paths, trees near structures, boundary fencing | Soil stability, localized flooding risks |
| Roof Exterior | Tiles, metal sheets, flashings, valley irons, gutters, downpipes | Water ingress points, weathering damage |
| Roof Interior | Ceiling joists, rafters, purlins, insulation layout, electrical clearance | Framing deflection, structural alterations |
| Building Exterior | Brickwork, mortar, external cladding, weep holes, damp-proof course | Settlement cracking, rising damp access |
| Building Interior | Plasterboard walls, ceilings, windows, internal doors, flooring | Internal movement, operational defects |
| Subfloor Space | Foundation piers, timber bearers, soil dampness, ventilation points | Pier subsidence, timber rot, pest risk |
Conclusion
A professional building inspection is an incredibly detailed, comprehensive audit that leaves no stone unturned. By utilizing a meticulous checklist spanning from the outer site boundaries to the deepest corners of the subfloor crawlspaces, inspectors remove the guesswork from property evaluations. Understanding this checklist helps property stakeholders appreciate the depth of an inspection and provides a blueprint for maintaining a safe, secure, and structurally sound building.