How Subfloors Increase Your Termite Risk And What To Do About It

Subterranean termites come up from underground to attack homes, meaning the first signs of damage can usually be seen in the subfloor. If you’re buying a home and can’t get to inspect the subfloor (or currently live in a property with a subfloor), the likelihood is that there has been no termite inspection for some years.

This is exactly what happened to Martin, who bought his dream home in Sydney in 2000. A timber pest inspection at the time told him there were no termites. Last year Martin decided to undertake some renovations, and what he found horrified him. The windowsill literally fell away in his hands (dry rot, and a warning sign of a termite friendly environment). When he began removing gyprock from the walls, the extensive termite damage was clear to see.

On inspection, Martin’s subfloor was found to be riddled with termites. Termite leads ploughed a path from the soil to the floor joists. The damage was estimated at many thousands of dollars in materials, plus labour.

How is a subfloor built?

A floor consists of three layers: the joists, the subfloor, and the top-floor. The joists support the subfloor and the subfloor is attached to the top-floor (tiles, hardwood, or carpet). The subfloor is usually made of plywood or pine: termite food.

Termites make their way up supporting joists to the subfloor, where they can cause extensive damage before then attacking the rest of the house.

How to spot termite damage to subfloors

There are a number of signs that indicated termite damage to the subfloor:

  • Squeaking floors
  • Sagging floors
  • A top floor layer that is detached from the subfloor
  • Loose floor tiles


How to handle termite infestation in your subfloor

If you notice any of the signs above, you should have your home inspected for termites. A plan of action to remove the termites and repair the damage should then be create. Damaged areas will need to be removed and replaced, with particular attention paid to nearby wooden structural timbers, including adjacent floor joists.

Work should be undertaken in this order:

  • Inspection
  • Infestation treatment
  • Preventative measures taken
  • Second Inspection to determine eradication and control
  • Repair work

How to protect your subfloor from termites?

Of course, the best way to tackle termites is to be prepared: prevention is always better (and cheaper) than cure. Here are five things to do to ensure your subfloor remains termite free:

  • Regularly inspect for termites (with a maximum of 12 months between inspections)
  • Ensure the subfloor is well ventilated, to prevent moisture build-up
  • Ensure adequate drainage
  • Treat timbers against termite attack

If you would like to better protect your most valuable investment – your home – and help it to increase in value then contact us today.