# 165 ft Round PEB — Member & Material Schedule
## Steel Grade: ASTM A36/A36M (Fy = 250 MPa, Fu = 400 MPa) — LOWEST SPEC

> **Design note:** Rafters **upsized ISMB 450 → ISMB 600** to satisfy LRFD at A36
> (ISMB 450 utilization ~124% = FAIL; ISMB 600 ~57% = PASS).
> Columns retained **ISMB 600** (pass with reserve). Apex ring CHS 406.4×12.5 adequate.

## Geometry
- 165 ft dia, eave 18 ft, apex 26.25 ft, 1:10 cone
- 20 perimeter columns; 4 internal columns @ r = 41.25 ft, h = 22.125 ft, 90° apart
- 20 long rafters (12.637 m) + 4 short rafters (11.424 m)
- 8 ft circular apex ring (torus) — no square inner ring beam
- Purlins Z200×75×1.6 @ 1.5 m c/c — 199 lines, 1,456.7 m

## Member Counts & Tonnage
| Group | Section | Qty | Mass (kg) | Mass (t) |
|---|---|---:|---:|---:|
| Columns (perim 20 + int 4) | ISMB 600 | 24 | 18,183 | 18.18 |
| Rafters (long 20 + short 4) | ISMB 600 | 24 | 39,692 | 39.69 |
| Apex ring torus | CHS 406.4×12.5 | 1 | 935 | 0.93 |
| Purlins | Z200×75×1.6 | 199 | 9,469 | 9.47 |
| Sag rods | 12 mm | — | 1,296 | 1.30 |
| Plates / bolts / cleats | — | 192 | 3,122 | 3.12 |
| **TOTAL** | | | **72,696** | **72.70** |

## Cost @ Rs 255/kg
**PKR 18,537,576**  (≈ Rs 18.54 M)

> Rate flagged **ASSUMED A36 MILL RATE — CONFIRM** (A572 Gr50 PEB rate was Rs 285/kg). Editable in the BOQ sheet rate cell.

## A36 vs A572 Gr50 — Cost Comparison
| Scheme | Tonnage | Rate | Cost |
|---|---:|---:|---:|
| A572 Gr50 (ISMB 450 rafters) | 58.49 t | Rs 285/kg | PKR 16,669,650 (16.67 M) |
| A36 (ISMB 600 rafters) | 72.70 t | Rs 255/kg | PKR 18,537,576 (18.54 M) |
| **Delta** | +14.21 t (+24%) | −Rs 30/kg (−10.5%) | **+11.2%** |

**Conclusion:** A36 is **~11% MORE expensive** here — the **+24% tonnage penalty** from up-sizing rafters to ISMB 600 **exceeds the 10.5% per-kg saving**. A572 Gr50 remains the economical grade for this structure.

## Exclusions
Sheeting, foundations, erection, paint, transport, 3–5% fabrication wastage.