Squeaky and bouncy timber floors are among the most common complaints from owners of older Wagga Wagga homes. They are annoying, embarrassing when guests visit, and sometimes alarming. The good news is that most floor noise in older homes is harmless, the result of normal timber movement or dried-out fasteners. The less good news is that in some cases, squeaks and bounce are early indicators of stump failure or foundation movement that will worsen if not addressed. This guide helps you tell the difference. For more on the warning signs of stump failure, see our guide on signs your house needs restumping.
Quick answer (BLUF)
Squeaks in timber floors are usually caused by floorboards or joints moving against each other as timber dries with age, typically harmless. Bounce (spring in the floor) indicates insufficient support, which can be a simple span issue or, more seriously, a stump that has failed or sunk. New or worsening bounce in a localised area is worth investigating as a potential foundation issue.
Why timber floors squeak
Timber moves. It absorbs moisture and expands, loses moisture and contracts. Over the decades, the tongue-and-groove joints of traditional hardwood flooring dry out, the timber shrinks slightly, and boards begin to move against each other when walked on. This movement produces squeaks.
The most common causes of floor squeaks are:
- Dried-out board joints. The tongue-and-groove fit becomes slightly loose as timber dries. Walking on the board causes it to rock slightly, producing friction and noise.
- Subfloor nail pops. Floor nails driven into joists at the time of construction can work loose as timber dries and movement occurs. A loose nail squeaks as the board moves up and down on it.
- Joist deflection. As floor joists age and dry, they deflect more under load. Board ends sitting on joists that flex each time they are walked on produce squeaks.
- Particle board or plywood squeaks. Post-war homes often have particle board or plywood subfloor sheeting. These materials delaminate or swell with moisture over time, and squeaks develop as sheets rub against each other or against the joist.
None of these causes are inherently structural or foundation-related. They are normal aging phenomena in timber floor construction.
When squeaks indicate a foundation problem
Squeaks become a potential foundation indicator when:
- They are new. Squeaks that appeared suddenly, over a few months, not decades, suggest a change in the subfloor condition. A stump that has recently failed, a joist that has lost its bearing, or a significant moisture change in the subfloor can produce new squeaks.
- They track a pattern across the floor. If squeaks are concentrated in one area of the home, say, along one side of the main hallway, and that area also shows other signs (a very slightly sloping floor, a door that recently started sticking), the pattern may reflect localised foundation movement.
- They are accompanied by bounce. Bounce is a more significant indicator than squeaks alone (see below).
What causes bounce in timber floors
Bounce, a springy, unsupported feel when walking on the floor, indicates that the floor is not adequately supported. This can occur for several reasons:
Stump failure. If a stump has sunk, rotted, or shifted, the bearer it supports has effectively lost a support point. The floor above that area is now spanning further than designed, like a trampoline. This is serious.
Joist failure. Timber joists that have been softened by decay, termite damage, or moisture can develop mid-span deflection. Walking on the joist produces pronounced bounce. Joist failure is structural and must be repaired.
Loose bearer-stump connection. In older homes, bearers sitting on the cap of a stump can work loose over time, particularly if the stump has tilted. A bearer with intermittent or insecure contact with the stump produces bounce.
Over-spanned joists. If a stump has been removed, relocated, or simply omitted during construction, the joists may be spanning a greater distance than they were designed for, resulting in bounce even in a relatively new installation.
Particle board delamination. Particle board that has absorbed moisture can delaminate and become soft, producing localised bounce. This is a flooring issue rather than a structural foundation issue, though the moisture ingress that caused the delamination may still indicate a drainage or stump problem.
How to assess floor bounce
The simplest test is to walk the floor systematically, every room, every corridor. Note areas where the spring or deflection is noticeably different from the rest of the home.
Then access the subfloor (typically via a floor access hatch in the hallway, bathroom, or laundry) and look directly at the stumps in the affected area:
- Is the stump vertical, or has it tilted?
- Does the bearer sit flush on the stump cap, or has it lifted?
- Is there any sign of decay (softness, darkening, mushroom smell) in the stump or bearer?
- Is the soil beneath the stump solid, or has it pulled away (indicating the stump has sunk into softened soil)?
If you observe any of these indicators, get a professional assessment promptly. Stump or joist failure that allows floors to flex excessively can progress to floor structural failure if left unaddressed.
FAQs
My floors have always been slightly springy, is that normal for old timber construction?
Some bounce is inherent in timber floor construction, particularly in homes with long joist spans or wide spacing between bearers. An older home that has always had some spring in the floor and has no associated signs of foundation movement (no sloping, no sticking doors, no cracking) is most likely experiencing normal timber floor behaviour, not a structural problem.
My floor squeak has moved, it used to be near the bathroom but now it is in the hallway. Is that significant?
A squeak that “migrates”, appearing in new locations as the floor settles and joists flex, can indicate progressive movement in the subfloor. This pattern is worth monitoring. Check whether the overall floor level has changed and whether there are any other signs of foundation movement.
Can I fix floor squeaks from above, or does it require subfloor access?
Minor squeaks from dried-out board joints can sometimes be addressed from above by injecting talcum powder, powdered graphite, or a fine lubricant into the joint. For squeaks caused by loose nails or lost bearing, access from below is more effective, securing loose joists, re-blocking bearers, and addressing the structural cause.