# Code Lookup

This group does not calculate — it looks up. Cover varies with exposure class and element type, seismic class depends on intensity, structural form and height together, confinement length depends on seismic class and column dimension, live load depends on occupancy, and fire compartment size depends on building class and whether sprinklers are fitted.

The trap is incomplete conditions. Give an intensity without a structural form and the seismic class cannot be fixed. Give a floor area without saying whether the building is single-storey or sprinklered and the compartment size cannot be checked. So every tool makes its preconditions explicit and refuses to answer until they are all supplied — one extra click is better than a number based on the wrong conditions.

- Category page: https://jianzhujisuan.com/en/c/code-lookup
- Data checked: 2026-10-25

## Tools in this group

- [Concrete Cover Thickness Lookup](https://jianzhujisuan.com/en/concrete-cover): Minimum cover from exposure class and member type, with every code correction applied.
- [Seismic Detailing Class Lookup](https://jianzhujisuan.com/en/seismic-grade): Intensity, system and height in; detailing class and height check out.
- [Column Confinement Zone Calculator](https://jianzhujisuan.com/en/column-hoop-zone): Confinement length, hoop spacing and bar size for each detailing class.
- [Floor Live Load Lookup](https://jianzhujisuan.com/en/live-load): Pick an occupancy and read the characteristic live load in kN/m².
- [Fire Compartment Area Lookup](https://jianzhujisuan.com/en/fire-compartment): Category, fire rating and sprinklers in; compartment limit out.
- [Travel Distance to Exit Lookup](https://jianzhujisuan.com/en/egress-distance): Travel distance by occupancy, with all three code corrections.
- [Egress Width Calculator](https://jianzhujisuan.com/en/egress-width): Occupants times the per-100-persons index gives total width and exit count.
- [Concrete Strength Acceptance Calculator](https://jianzhujisuan.com/en/concrete-test-strength): Switches between statistical and non-statistical criteria automatically.

## Questions

### What cover should I use?

Per GB 50010 Table 8.2.1, by exposure class and element. Indoor dry conditions give 15 mm for slabs and walls, 20 mm for beams and columns; damp or exposed conditions 20 and 25; the more severe classes go to 25/35 and 30/40. Footings on blinding carry an additional 40 mm requirement.

### How is the seismic class determined?

From three inputs together: intensity, structural form and building height. At intensity 7 a frame up to 24 m is class 3 and above 24 m is class 2, while a shear wall structure at the same intensity comes out one class lower. Podiums, towers and basement top restraint have their own adjustment rules on top.

### What live load applies to a floor?

Per GB 50009 Table 5.1.1: residential 2.0 kN/m², offices 2.0, classrooms 2.5, corridors and lobbies 2.5, residential stairs 2.0, balconies 2.5, retail 3.5, book stacks 5.0 and plant rooms 7.0. Partition and equipment loads are additional and must not be ignored.