Auditoriums · HUB · REV 2026-10-06
Auditoriums
An Auditorium is a room in which the speaker can be seen and the sentence understood. Rake, aisle, and wheelchair position are part of that. A chair count taken from floor area is not a legal capacity.
What this gate is
This gate is for lecture and assembly rooms, not for a theatre fly tower and not for a stadium bowl. The engineering question is whether a seated person sees the speaker over the person in front, whether speech arrives before RT60 or HVAC noise buries it, and whether aisle width matches the adopted code rather than a furniture plan.
Design fixes the rake, the comfortable capacity, and the speech criterion. Construction builds the rake and installs seats, the acoustic envelope, and AV infrastructure while the room is still a site. No figure on this gate is copied into an occupancy permit. The page replaces neither ISO 3382-1, nor IEC 60268-16, nor the egress code.
What is published now
Auditorium design
Rake, sightlines, speech, aisles, and access. Capacity taken from area is not a legal capacity.
Auditorium construction
Forming the rake, fixing seats, closing the envelope, and installing infrastructure while the site has not been handed over.
Pages that complete the room
Seats, RT60, STI, and projectors are read on their own pages. This gate does not abbreviate them.
Outside the scope
No chair catalogue, no fire classification, and no city page for lecture halls.
When to open this gate
A lecture or assembly brief
When a speaker is a distinct source and the sentence must be understood from the last row.
A dispute about seat count
When the owner wants a number from area and the code wants aisles and exits. The gate separates the two numbers.
Wrong scope
If the ask is an unamplified concert room, a theatre with a fly tower, or a stadium, this gate is not where that design belongs.
How to read the subject
- 01
Fix the speech source: a platform, a lectern, or more than one position, and whether reinforcement is in the brief or only a fallback.
- 02
Build the rake from the sightline, not from a stock slope, and place wheelchair positions on a sightline rather than in a blocked corner.
- 03
Separate comfort capacity from legal capacity: row spacing is not aisle width and is not the seat count the code allows.
- 04
Write the speech criterion — STI to IEC 60268-16 and RT60 to ISO 3382-1 — then hand the room to construction while it can still be changed.
What this gate does not do
Copying a capacity from another project
Aisle geometry, row length, and the local code change the number. The previous project is not a legal reference.
A flat room named a rake
If every seat needs a stable sightline and the floor does not rake, the drawing does not match the name.
Wrong scope
The gate issues no occupancy permit, no fire certificate for chairs, and no Line Array design. Those are other scopes with their own criteria.
Questions designers and owners ask
If I divide the floor area by a chair area, do I get capacity?
You get a sketch only. Legal capacity comes from the adopted egress code: exit width, row length, and travel distance, not from that division.
What does STI have to do with the room?
If speech is the programme, STI as described in IEC 60268-16 is a way to discuss intelligibility. The page sets no pass mark. The mark is written in the brief and measured by the named method.
Is the rake one slope for every hall?
No. C-value, row spacing, and eye height usually produce a varying section. Copying a slope from a photograph drops the rear or the front.
When is this gate not enough?
When the work needs a stage tower, isolation between cinema screens, or a hospitality box in a stadium. Open the gate for that type.
Is a measurement in the concrete shell a handover?
No. RT60 and background noise change with seats, doors, and HVAC in operating mode. A shell measurement is a note, not a handover record.
Technical sources
- IEC 60268-16
Objective rating of speech intelligibility by STI. A score on this gate is not a measurement. The page does not replace the standard.
- ISO 3382-1
Measurement of room parameters in performance spaces, including RT60. A lecture hall may fall inside its scope or may need a stated method if the use differs. The page does not replace the document.
- The building, fire, and egress code adopted by the project
Legal capacity, aisle width, and the fire performance of finishes come from that code. The gate does not replace it and names no city.
Last editorial review: 2026-10-06. Review means the text was checked, not that a project was measured.
Turn the question into a brief
A study starts from room volume, use, and existing condition, not from a product name. Fill the brief and copy it.
Project study form