For this part of the inspection you will need full PPE, you will spend a lot of your inspection time on your back, and crawling around wet, dusty, smelly conditions sometimes all of these at once in different areas under the house Mosquito.
The subfloor has a purpose in a house, normally to provide good ventilation and drainage as well as servicing certain services from. They also provide a good home for insects, spider’s snakes and dead cats and many other nasties. It is a must that you educate your client in how to keep this area junk free.
Inspection
One of the first things that you look for when entering a sub floor, is a termite treatment sign which may be affixed to the first bearer that you come into contact with, other places where signs may be placed are in the power/meter box or on a pole (power pole). You must wear full PPE when inspecting the subfloor, as there may be chemicals that have been sprayed for termites or even dusts used in general pest treatments.
Look around, can you see air vents, are there enough?Start from the left of the entrance of the subfloor and go all around, and check all four sides of any support pier. Once all the support piers have been inspected then re-start and do the perimeter walls if it is an enclosed subfloor, if it is not enclosed, check slab verandah, and any service pipes that enter the house from beneath, as these are a favourite route into a house or building for termites.
To summarise what needs to be checked and how:
Look at all the walls for termite leads
Check all piers from all angles for termites
Check all structural timbers (bearers, joists etc) for soundness
Inspect the flooring for borers, decay and termite attack.
Once you have checked the above, roll over on to your back and probe and sound timbers that are supporting the floor of the building. You use the same process of sounding as you did in the roof and the interior of the building.. If all looks good, be very vigilant for small mud tubes between cracks in the exterior wall, and double floor bearers etc,Check for any old form work left by the builders and recommend to the owners that these timbers be removed as soon as possible put this in your written report. Look for any old off cuts of wood or stored goods under the house, as this can be a start point for the termites as they can build self-supporting leads.
Floorboards
Normally floorboards are made from softwoods; more modern houses will have chip board under their carpets, to save money. White cypress pine is resistant to borers and termite attack, but Baltic pine and alpine ash are not these are a few of the most common used in floorboards.Check for Furniture beetle attack (Anobium punctatum), which is commonly found in softwood flooring and furniture, the identifying signs are round holes approximately 1-2mm in diameter on the subfloor side of the floorboards. If you do find these holes, look for the frass on the bearers or on the piers directly beneath the holes, if you cannot find the frass, bang the floor with you fist and it will drop out, then rub the frass between your finger and your thumb, if it has a gritty rough feel, you can be assured it is furniture beetle. If it is smooth like flour, then it will be Powderpost beetle, however you will know that if it is Powderpost beetle, the timbers you are dealing with will be hardwoods, as Powderpost beetles can only re-infest hardwoods. Another way of identifying Furniture beetle is if you cut off a slice of damaged timber, it will look like an Aero chocolate or a violet crumble inside. In your written report you should if you find borer damage recommend that the affected timbers be sprayed with a registered spray for 3 consecutive years or replace the timbers. If they do replace the timbers, then recommend that those timbers that have been replaced be burnt as soon as possible do not leave them hanging around they must be destroyed.
Furniture Beetle Facts
Attacks softwoods, but sometimes can attack hardwoods
Prefers woods over 20 years service
White cypress pine and most hardwoods are resistant
Attacks flooring, panelling and furniture
Seldom attacks roof void timbers because of heat
Generally occurs in coastal Australia
Life-cycle can be up to three years
Chemical treatment is ok if damage is slight
Replace timbers and burn if damage is extreme
Very similar to the Queensland pine beetle. Queensland pine beetle is lighter, less shiny and narrower than furniture beetle.
Scientific name is Anobium punctatum.
Ant Capping
It should be noted, that ant capping is not designed to prevent termites entering and attacking a building, and they are placed there so that if they come up the piers, they will have to show themselves by means of their mud packing leads. It is so important that we make note of the condition of the ant caps, as any defect in the ant capping such as a break or rusted through will allow the termites to enter the building. Not all buildings have ant cappings those built previous to World war 2 will not have them so your inspection will be harder.