DIY Building Inspection Checklist

Are you looking for an ‘unofficial’ DIY building inspections checklist in NZ?

When you first inspect a house, you generally look at the property from an emotional point of view. That’s normal.

Following your first ’emotion’ inspection, you then need to look at the property with a ‘next step’ set of eyes. Take the list below with you and see if you can detect any initial ‘red flags‘ before you call in the profession inspectors!

NOTE: Do not make any purchase decisions based off this list, because it doesn’t include moisture testing procedures, or the experience of a qualified inspector. This list only serves as a guide to help you view the property from a different angle with areas to look at which you may not have thought of yourself. Always use a professional building inspection company prior to purchasing a house!


The Garden

  • Check the general condition of fences and gates. Is there any visual evidence of rot, bora etc?
  • Are there any large trees to close to the house? The root system of the trees could potentially cause structural cracks to the home , particularly in brick or veneer homes, and concrete slabs.
  • Are there any ‘sharp’ or ‘poisonous’ trees on the property that would be dangerous to kids?

Out-Buildings – Garages,  Sleep outs, Granny Flats

  • Does it look like the structural integrity off any external walls is sound? Any swollen skirting boards? Mould?
  • Look for low hanging wires, exposed wires around power points, any potential fire hazards?

Outside Walls

  • Carefully inspect the walls to ensure that they are straight. Stand at one end of the home and look down the line of the wall. In timber houses, sagging weatherboards could mean the timber piles supporting the home may have rotted, or concrete piles or brick piers have subsided.
  • Check for rotten weatherboards, window frames, doors and verandah posts. Sometimes weatherboards have been recently painted, but there is actually rot sitting under the thin coat of paint!
  • Thoroughly check for cracks in the mortar between the bricks. Also check to see if it’s crumbling away.
  • In the case of a brick house, check the weep holes between the bricks nearest to the ground are unblocked.
  • Take a look up at the soffits around the home. Are they mouldy, sagging or fitted incorrectly?

On the Roof

  • Lean your ladder against the guttering and look for a wavy roof line.
  • Look for broken roof tiles and loose ridge and valley tiles.
  • Check that corrugated iron sheets are in good condition and well nailed/screwed down.
  • Ensure that valley and eaves guttering are free from holes and rust. Even small holes can create large leaks.
  • Make sure that flues and chimneys are structurally safe and the flashings around them are secure.

Under Timber Floors

  • Look under the floor for props or bricks holding up the floor instead of stumps, piers or dwarf walls
  • With timber piles, look for piles with the heaviest water stain.
  • Inspect timber framing and floors generally for rot, mould and evidence of bora.
  • Check to see that the ground is not excessively wet. This can case rising damp.
  • If you are in any way unsure about bora, the house should be checked by a specialist.

In the Roof Space

  • Look for sagging roof framing, cracked or broken tiles, rusty iron roofing and leaking ridges or valleys.
  • Check for shoddy or damaged electrical wiring. Do not touch!
  • A pungent odour or rat-like droppings could indicate the presence of vermin.
  • Note whether or not the ceiling has been insulated. What type of insulation.. pink batts, spray insulation?

Concrete Floors

  • Although the underside of the concrete floors cannot be inspected check if there is any exposed perimeter to ensure that the plastic waterproofing membrane is not exposed.


These checks should be carried out in each room of the house.

Timber Floors

  • At regular intervals, jump lightly on the floor to detect any rotten floorboards, borer infestation or looseness in the floor framing.
  • Check to see if the floors are level, or there are gaps between floor and skirting. If piles or piers are sinking, floors will always fall away from fireplaces or brick walls.

Concrete Floors

  • Look for signs of dampness, such as lifting or buckling floor tiles and rotten carpet.
  • Ducted heated systems are millimeters wide, they could indicate a significant structural problem.


  • Check that walls are straight and true.
  • Look for cracks and general movement and be particularly wary of freshly painted or wallpapered areas. Any signs of leaks?
  • Carefully inspect brick walls for signs of dampness.
  • Tap solid brick walls for a hollow sound or a change in tone.
  • Look for cracks beside chimneys and look for doorways and windows that aren’t square, or are jamming.
  • Lightly tap walls and tiled surfaces with the handle of your screwdriver.
  • Look at all skirting boards. Is there any swelling consistent with moisture damage?
  • Is there a cavity system behind the wall, or is the external cladding fixed directly onto the timber frame?


  • Check that ceilings are straight and true, and look for cracks or signs of movement at the cornices.
  • Look for water stains and mould growth which could indicate excessive condensation, roof leaks or missing insulation.

Windows and Ventilators

  • Make sure that windows can be opened and check for broken window panes.
  • Check for excessive condensation and mould growth on windows and walls. Look at the back of curtains for mould… this would indicate the room condensates, therefore it may be a damp room.
  • Are the windows single glazed, or double glazed?
  • Any rot on the window sills?

Electrical Systems

  • Check that the light switches and power points work.
  • Test all power points with the tester.
  • If you are at all in doubt about the condition of the electrical system, you should have it checked by a qualified electrician or thermal imaging.

Plumbing Systems

  • Check all plumbing fittings for cracks or leaks.
  • Test the water pressure in hot and cold taps.
  • Partially fill the bath or laundry tubs and observe whether or not the water drains away properly.
  • Look for damp ground in the vicinity of the drains.
  • Check for dampness and soft soil where down pipes meet the ground.


Examine the house for appropriate room layout, orientation to the sun, views, relation to neighbours, traffic noise, and if not optimal, whether the house can be improved at an affordable cost.

Renovations and Extensions

If the house has recently been renovated, or if extensions have been carried out, check with the local Council to ensure that a CCC was obtained. Illegal alterations could become your responsibility, particularly if they contravene the building regulations. Some older homes had extensions built in the 90’s and early 2000’s when they used alot of untreated timber framing. Untreated timber can rot fast if exposed to any moisture.

If you are buying with a view to doing extensions in the future, check Council requirements for set-back distances, maximum site coverage and restrictions on types of construction. You may need to seek professional advice.

If you require a moisture test on the home, call us for a free quote!