Structural Engineering · Drg No. MHBL-04 · All Floors
Beam Layout — All Floors
Mayank's House · G+1 Residential · 7600×11000mm · 3×4 Grid · M20/Fe500
Plinth: PB 300×450
GF: GB 230×450
FF: FB 230×375
Spans: 3500/3800/4000mm
12 Cols · 7 Beam Lines/Floor
M20 Concrete · Fe500 Steel
Drg. No. MHBL-04
Date: 01.03.2026
Scale: NTS
Rev: 00
Plinth Level  +450mm
Ground Floor  +3450mm
First Floor  +6450mm
All Floors Overlay
Floor-to-Floor Height: 3000mm  |  Total 3 Beam Levels

Plinth Level Beam Layout

+450mm NGL
300
Width mm
450
Depth mm
7
Beam Lines
12
Spans
2T16
Bottom Bars
T8@150
Stirrups
+450
Level mm

Plinth Beam Plan — PB 300×450mm

7 BEAM LINES · 12 SPANS · ALL CONTINUOUS · 300×450mm THROUGHOUT
PB-LA · 300×450 PB-LB · 300×450 PB-LC · 300×450 PB-T1 · 300×450 PB-T2 · 300×450 PB-T3 · 300×450 PB-T4 · 300×450 3500×3800mm 3500×3800mm 3500×3800mm 3500×3800mm 4000★×3800mm 4000★×3800mm A1 B1 C1 A2 B2 C2 A3 B3 C3 A4 B4 C4 A B C 1 2 3 4 3800 3800 3500 3500 4000★ ← 7600 mm → ← 11000 mm → N
PB 300×450mm
Col 300×300
4000mm bay ★

Plinth Beam Schedule

PB-LA/LB/LC + PB-T1..T4
BeamDirSizeSpanBottomTopStir.
PB-LALong.300×4503.5+3.5+4.02T162T12T8@150
PB-LBLong.300×4503.5+3.5+4.02T162T12T8@150
PB-LCLong.300×4503.5+3.5+4.02T162T12T8@150
PB-T1Trans.300×4503.8+3.82T162T12T8@150
PB-T2Trans.300×4503.8+3.82T162T12T8@150
PB-T3Trans.300×4503.8+3.82T162T12T8@150
PB-T4Trans.300×4503.8+3.82T162T12T8@150
Plinth Beam Notes
· Level: top of beam = FFL = +450mm NGL
· Function: tie columns, prevent settlement
· All beams continuous over supports
· Extra 2T12 @supports (L/4 each side)
· Stirrups @100 in L/6 confine zones
· Anti-termite treatment before casting
· Cover to stirrup: 30mm

Level + Size Summary

ParameterValue
Beam level+450mm NGL
Beam size300 × 450mm
Total beam lines7
Total spans12
Max span4000mm (L-dir bay 3-4)
Effective depth396mm (d=450-30-24/2)
ConcreteM20
SteelFe500 (HYSD)

Ground Floor Beam Layout

+3450mm (GF Slab)
230
Width mm
450
Depth mm
7
Beam Lines
12
Spans
2T16
Bottom Bars
T8@150
Stirrups
+3450
Level mm

Ground Floor Beam Plan — GB 230×450mm

7 BEAM LINES · SAME GRID AS PLINTH · 230×450mm · 3.5+3.5+4.0m LONGITUDINAL
Kitchen / Bedroom Bedroom Living / Dining Car Parking / Entry GB-LA · 230×450 GB-LB · 230×450 GB-LC · 230×450 GB-T1 · 230×450 GB-T2 · 230×450 GB-T3 · 230×450 GB-T4 · 230×450 3500×3800 3500×3800 3500×3800 3500×3800 4000★×3800 4000★×3800 A1 B1 C1 A2 B2 C2 A3 B3 C3 A4 B4 C4 A B C 1 2 3 4 3800 3800 3500 3500 4000★ ← 7600 mm →
GB 230×450mm
Room zones (GF)
4000mm bay ★

GF Beam Schedule

GB-LA/LB/LC + GB-T1..T4
BeamSizeSpan(s)Bot.TopStir.
GB-LA230×4503.5+3.5+4.02T162T12T8@150
GB-LB230×4503.5+3.5+4.02T162T12T8@150
GB-LC230×4503.5+3.5+4.02T162T12T8@150
GB-T1230×4503.8+3.82T162T12T8@150
GB-T2230×4503.8+3.82T162T12T8@150
GB-T3230×4503.8+3.82T162T12T8@150
GB-T4230×4503.8+3.82T162T12T8@150
GF Beam Notes
· Level: soffit at GF slab = +3450mm
· GF beams are shallower than plinth
· Width 230mm (vs 300mm plinth) — lighter
· Slab span between beams ≤ 3.8m OK
· Cantilever at OTS: special check needed

GF vs Plinth Comparison

ItemPlinth (PB)GF (GB)
Width300mm230mm
Depth450mm450mm
Level+450mm+3450mm
Bot. bar2T162T16
Top bar2T122T12
StirrupsT8@150T8@150
FunctionTie + settleSlab support

First Floor Beam Layout

+6450mm (FF Slab / Roof)
230
Width mm
375
Depth mm
7
Beam Lines
12
Spans
2T12
Bottom Bars
T8@150
Stirrups
+6450
Level mm

First Floor Beam Plan — FB 230×375mm

REDUCED DEPTH FOR LIGHTER ROOF LOAD · 230×375mm · 2T12 BOTTOM · T8@150
Bedroom / Toilet Master Bed / Toilet Lounge / Dresser OTS / Open Area FB-LA · 230×375 FB-LB · 230×375 FB-LC · 230×375 FB-T1 · 230×375 FB-T2 · 230×375 FB-T3 · 230×375 FB-T4 · 230×375 3500×3800 3500×3800 3500×3800 3500×3800 4000★×3800 4000★×3800 A1B1C1 A2B2C2 A3B3C3 A4B4C4 A B C 1 2 3 4 3800 3800 3500 3500 4000★ ← 7600 mm →
FB 230×375mm
Room zones (FF)
4000mm bay ★

FF Beam Schedule

FB-LA/LB/LC + FB-T1..T4
BeamSizeSpan(s)Bot.TopStir.
FB-LA230×3753.5+3.5+4.02T122T10T8@150
FB-LB230×3753.5+3.5+4.02T122T10T8@150
FB-LC230×3753.5+3.5+4.02T122T10T8@150
FB-T1230×3753.8+3.82T122T10T8@150
FB-T2230×3753.8+3.82T122T10T8@150
FB-T3230×3753.8+3.82T122T10T8@150
FB-T4230×3753.8+3.82T122T10T8@150
FF Beam Notes
· Reduced depth 375mm (less load)
· Lighter steel: 2T12 bot, 2T10 top
· Roof beam carries slab + LL only
· Same grid, same spans as GF/Plinth
· Parapet wall load on perimeter beams

All Floor Size Matrix

FloorSizeLevelBot.Depth
Plinth300×450+4502T16450mm
GF230×450+34502T16450mm
FF/Roof230×375+64502T12375mm

All Floors — Overlay & Elevation Summary

Composite View

Building Elevation — Beam Levels & Sizes

SCHEMATIC SECTION SHOWING ALL 3 BEAM LEVELS · NOT TO SCALE
NGL B1 B2 B3 B4 PB 300×450 PB 300×450 PB 300×450 +450 GB 230×450 GB 230×450 GB 230×450 +3450 FB 230×375 FB 230×375 FB 230×375 +6450 +450mm 3000mm GF floor-to-floor 3000mm FF floor-to-floor TOTAL HEIGHT 6450mm Span 3500mm Span 3500mm Span 4000mm ★

Master Beam Schedule — All Floors

COMPLETE SUMMARY
FloorPrefixSizeLevelBottomTopStirrupsLines
Plinth PB- 300×450 +450mm 2T16 2T12 T8@150 7
GF Slab GB- 230×450 +3450mm 2T16 2T12 T8@150 7
FF/Roof FB- 230×375 +6450mm 2T12 2T10 T8@150 7
Design Rationale
· Plinth 300 wide — transfers column loads + acts as tie beam; larger because it also resists differential settlement
· GF beams 230×450 — carries GF slab load (LL 2.0 kN/m²) + FF column load above
· FF beams 230×375 — lighter, only roof slab (LL 1.5 kN/m²); reduced depth OK for clear spans ≤4.0m
· All 3 levels share identical 3×4 grid — simplifies formwork, consistent shuttering
· 4.0m bay (rows 3–4) uses same steel; extra stirrups T8@120 in that span
· All beams continuous over columns — moment redistribution reduces peak sagging