Footsteps, voices and televisions can all travel between floors, but they do not necessarily follow the same route.
A heavy step above may be felt through the structure. A conversation or television may pass through the air, floor cavity, ceiling and adjoining walls.
Understanding the difference helps explain why one acoustic measure may improve one type of noise while having less effect on another.
Quick answer: Footsteps and furniture movement mainly create impact noise, while voices, televisions and music are mainly airborne. Floors and ceilings work together as one acoustic system, and sound can also travel around them through adjoining walls and structural connections.
Not all sound travels in the same way
Household noise is often grouped together as one problem.
In practice, there are important differences between sound travelling through the air and vibration entering the building structure.
This is why footsteps can remain obvious even when speech has become quieter, or why a television can still be heard despite a soft floor covering above.
Footsteps
Create impact vibration as feet make contact with the floor surface and structure beneath.
Dropped objects
Introduce a sudden impact that can travel through joists, floorboards, ceilings and adjoining structures.
Voices
Travel mainly through the air but can pass through floors, ceilings, walls, gaps and open circulation spaces.
Televisions
Produce airborne sound across a range of frequencies, with lower tones often behaving differently from speech.
Music and speakers
Can introduce stronger low-frequency sound and vibration, particularly where speakers contact floors or furniture.
Furniture movement
Chairs, beds and other items can create impact and scraping noise through direct contact with the floor.
What impact noise means
Impact noise begins when an object makes physical contact with the building.
Footsteps, dropped toys, moving chairs and exercise equipment all transfer energy into the floor.
That vibration can then travel through floorboards, joists, ceiling finishes and adjoining walls.
The floor finish matters. Hard surfaces may make certain impacts more noticeable, while softer finishes can help reduce some contact noise before it enters the structure.
However, the complete floor build-up still matters. A rug may soften a footstep without changing the cavity or ceiling below.
What airborne noise means
Airborne noise begins as sound travelling through the air.
Voices, televisions, radios, music and gaming audio are common examples.
The sound reaches the floor, walls and ceiling, causing those surfaces to vibrate. It may also pass through gaps around pipes, light fittings, doors and other openings.
Airborne sound can therefore travel through the main floor assembly or around it through adjoining structures.
The floor and ceiling form one system
The floor above and ceiling below should not be considered as completely separate surfaces.
They are connected by joists, cavities, fixings and structural junctions.
A change to the upper floor finish may influence impact noise. Material within the cavity may influence airborne sound transfer. The ceiling construction below can also affect how the assembly performs.
| Noise source | Noise type | Likely route | Useful first question |
|---|---|---|---|
| Footsteps above | Impact | Floor finish, boards, joists and ceiling structure | Is the noise caused by contact with the floor? |
| Conversation below | Airborne | Floor cavity, ceiling, walls and gaps | Can speech be heard clearly or only as background sound? |
| Television beneath a bedroom | Airborne | Floor, ceiling and adjoining wall routes | Is the sound mainly speech, music or low-frequency bass? |
| Chair scraping upstairs | Impact | Floor finish and structural vibration | Would reducing direct contact noise help? |
| Speakers on the floor | Airborne and vibration | Air plus direct contact with the structure | Are the speakers transferring vibration into the floor? |
| Dropped objects | Impact | Floor and ceiling assembly | Is the event occasional or part of regular room use? |
Sound can travel around the floor
Even where the main floor area is treated, sound may continue through other routes.
It may pass into an adjoining wall, travel through the structure and re-enter the room below. It may also move through service gaps, ceiling voids or open staircases.
This is often referred to as flanking transmission.
It explains why treating one obvious surface does not always remove the sound completely.
Where acoustic insulation may help
Within a suitable timber floor, acoustic insulation beneath the floor may help reduce some airborne sound transfer through the cavity.
Depending on the wider floor build-up, acoustic floor insulation may form one part of a broader approach that also considers floor finishes, ceilings, gaps and structural junctions.
Impact noise may require particular attention to the surface and resilient separation as well as material within the cavity.
The aim should be realistic improvement rather than a promise of complete silence.
Map the noise before treating the floor
Before choosing a measure, consider:
- Is the main problem footsteps, voices, television or furniture movement?
- Does the sound begin through direct contact with the floor?
- Can individual words be heard, or only general noise?
- What floor finish is currently present?
- Is the ceiling below fixed directly to the joists?
- Are there service gaps or openings through the floor and ceiling?
- Could sound be travelling through adjoining walls?
- What level of reduction is realistically needed?
Different noises need different expectations
Footsteps, voices and televisions may all be heard between the same two rooms, but that does not make them one identical problem.
Impact noise begins within the structure. Airborne sound begins in the air. Some sources, such as speakers, may involve both.
A useful acoustic recommendation should identify the dominant noise, explain the likely route and set realistic expectations for the proposed work.
Frequently asked questions
Are footsteps airborne or impact noise?
Footsteps are mainly impact noise because physical contact transfers vibration into the floor structure.
Are voices considered airborne sound?
Yes. Voices begin as airborne sound, although they can make floors, walls and ceilings vibrate as they pass through the building.
Will carpet stop footsteps being heard below?
Carpet and underlay may reduce some contact noise, but the joists, floorboards, ceiling and structural junctions still influence the result.
Can acoustic insulation reduce television noise?
It may help reduce some airborne sound transfer through a suitable floor cavity, although walls, gaps and flanking routes may still carry noise.
Why can I still hear sound after the floor has been treated?
The sound may be travelling around the treated area through adjoining walls, ceilings, gaps or other structural connections.
In the next article: Open-plan layouts improve light and connection, but removing walls and doors can also change how far everyday sound travels through the home.
Read: How Open-Plan Living Changes The Way Sound Moves Through A Home
