The direction is consistent, but the strength is modest
Across several reviews, the same pattern recurs: open-plan layouts are associated with lower individual and organizational performance than enclosed offices. A systematic review of 46 empirical articles concluded that open-plan offices can cut real-estate costs but tend to produce lower performance, a trade-off the authors describe as a productivity tax that outweighs the savings [3]. A separate systematic review comparing open-plan with cellular (enclosed) offices reached a similar conclusion, associating open-plan designs with negative psychological and work outcomes including reduced productivity [5].
The recurring weakness is how productivity is measured. Much of the underlying evidence comes from subjective questionnaires in which workers rate their own comfort, stress, and perceived output, rather than from objective counts of completed work [1]. That does not make the reports wrong, but it means the evidence is strongest for how workers feel about their output and weakest for how much output actually changes.
Why speech is the specific culprit
The distraction is not generic noise but intelligible speech. A review of 11 questionnaire-based studies in open-plan offices identified irrelevant speech, chatting, and telephone ringing as the main noise sources behind reported productivity loss, stress, and low comfort, tied to distraction and a lack of privacy [1]. The key word is irrelevant: overheard conversation competes with the task in a way that a steady hum does not, because the brain processes speech whether or not the listener wants to.
A laboratory experiment adds a physical dimension. Testing Chinese open-plan office acoustics, researchers varied speech intelligibility and reverberation time (how long sound lingers in a room) and found that in the short-reverberation setting, work performance dropped and speech disturbance rose as intelligibility increased; that trend did not appear in the long-reverberation setting [4]. At one middle intelligibility level, participants in the long-reverberation room showed less mental workload, faster task completion, and higher acoustic adaptability than those in the short-reverberation room [4]. The effects also appeared to differ by gender and noise sensitivity [4]. This is a lab study of a serial recall task, not a measurement of real office output, so it explains a mechanism rather than settling the size of the problem.
How large are the time losses? The honest answer is unmeasured
The question of magnitude is where the evidence thins out. The noise review documents that productivity loss occurs but does not quantify the extent of time lost to distractions [1]. The review of office concepts likewise reports lower performance without attaching a time figure [3], and the open-plan versus cellular comparison does not quantify time lost to distraction either [5]. A study of open-plan spatial dimensions examined productivity and mood but likewise did not quantify distraction-related time losses [2].
So the literature supports a qualitative claim — distractions happen, workers notice them, and performance tends to be lower — but not a quantitative one. Anyone quoting a precise number of minutes or hours lost per day is going beyond what these studies establish. The most defensible statement is that the losses are real enough to show up in performance and self-reports, while their size remains an open measurement problem.
What the evidence says can soften the effect
The noise review points to practical countermeasures: sound-absorbing surfaces, separate zones for different kinds of tasks, and headphones [1]. The authors caution that how well these work depends on human behavior and on whether they are economically feasible, so they are plausible mitigations rather than proven fixes [1].
The laboratory findings suggest that room acoustics matter in a non-obvious way: intelligibility, not just loudness, drives the interference, and the effect of intelligibility depended on reverberation time [4]. That is consistent with the idea that reducing how clearly speech carries — through absorption or zoning — could matter more than simply lowering overall volume, though this comes from a controlled task rather than from field tests of office output.
Sources used in this answer
Self-rated health implications of noise for open-plan office workers: An overview of the literature
A review of 11 questionnaire-based studies found irrelevant speech, chatting, and telephone ringing to be the main noise sources causing reported productivity loss, stress, and low comfort in open-plan offices, without quantifying time losses.
Larger or smaller? The effects of open-plan office spatial dimensions on human mood, productivity and economic benefit
A study of open-plan office spatial dimensions examined effects on mood, productivity, and economic benefit but did not quantify distraction-related time losses.
The productivity tax of new office concepts: a comparative review of open-plan offices, activity-based working, and single-office concepts
A systematic review of 46 empirical articles concluded that open-plan offices can reduce real-estate costs but tend to lower performance, imposing a productivity tax that outweighs the savings.
Effects of speech intelligibility and reverberation time on the serial recall task in Chinese open-plan offices: A laboratory study
In a laboratory serial recall experiment, higher speech intelligibility in a short-reverberation room was associated with decreased work performance and increased speech disturbance, a trend not seen in the long-reverberation room, with effects varying by gender and noise sensitivity.
A comparison of psychological and work outcomes in open-plan and cellular office designs: A systematic review
A systematic review comparing open-plan and cellular offices associated open-plan designs with negative psychological and work outcomes, including reduced productivity, without quantifying time lost to distraction.