Grid

Column grid spacings in metres, centre to centre, separated by commas. Numbers 1, 2, 3… run left to right; letters A, B, C… run top to bottom.

Spacings along X (left → right), m Spacings along Y (top → bottom), m

Your plan drawing (optional)

Upload a photo or image of your house plan to trace on. It stays on your device.

Image width, m Opacity

Shift right, m Shift down, m

Tap a grid point to add or remove a column.

Beams are the same on every floor and on the plinth. A slab is formed in every bay closed by beams on all four sides, unless you mark it as an opening (stair or duct).

Floors and heights

Number of storeys above plinth

Plinth height above ground, m Top of footing below ground, m

Plinth beams (tie beams at plinth level)

Materials

Concrete grade Steel grade

Exposure (IS 456 Table 3)

Starting member sizes (mm)

With auto-sizing on, any member that fails is enlarged in 50 mm steps and the frame is re-analysed until everything passes.

Column width (X)Column depth (Y)

Floor beam widthFloor beam depth

Plinth beam widthPlinth beam depth

Slab thickness Auto-size members to pass all checks

Gravity loads (IS 875 Parts 1 & 2)

Live load, floors, kN/m²Live load, roof, kN/m²

Floor finish, kN/m²Roof finish + waterproofing, kN/m²

Masonry unit weight, kN/m³Openings in walls, %

Parapet height, mParapet thickness, mm

Walls: outer beams carry 230 mm walls and inner beams 115 mm walls unless you change them in the Plan step (Walls tool).

Foundation

Safe bearing capacity of soil, kN/m²

Earthquake (IS 1893 Part 1:2016)

Seismic zone Soil type

Importance factor Frame type

Masonry infill walls (T = 0.09h/√d)

Wind (IS 875 Part 3:2015)

Basic wind speed Vb, m/s Terrain category

Force coefficient Cf

Check Vb for your town in IS 875 (Part 3):2015 Annex A.

Press Analyse & design in the Loads step to see the results.

Project

Project name Location Designed by

Open project file

How it works

Analysis: a full 3D frame model (6 degrees of freedom per joint) solved by the direct stiffness method, like STAAD. Columns are fixed at the top of the footings. Load cases: dead, live, earthquake X and Y, wind X and Y.
Loads: slab loads go to the beams as triangular / trapezoidal equivalent loads (IS 456 Annex D), walls and parapets as line loads, self weight automatically. Earthquake by the equivalent static method of IS 1893 (Part 1):2016 with cracked-section stiffness (0.35 Ig beams, 0.70 Ig columns) and the design eccentricity for torsion (1.5 e_si + 0.05 b); wind by IS 875 (Part 3):2015.
Design: 25 load combinations of IS 456 Table 18 and IS 1893. Beams for flexure, shear and deflection; columns for biaxial bending by strain compatibility (IS 456 cl 39.6) with minimum eccentricity and slenderness (effective length from IS 456 Annex E), and for shear; slabs by IS 456 Table 26; isolated footings for bearing, one-way and punching shear and bending. IS 13920:2016 ductile detailing for SMRF frames, including capacity shear in beams and columns, confining hoops, beam–column joint shear and the strong-column/weak-beam check.
Limits: regular buildings up to G+4 on a rectangular grid, analysed by the equivalent static method (taller buildings in zones IV and V need dynamic analysis — the tool warns you); soft storeys, stairs, water tanks and shear walls are not modelled. Every design must be checked and signed by a qualified structural engineer before construction.

Building Frame Designer — RCC house design from your plan