Free Tools
Beam & Column Size Estimator (Early Estimate)
Rough EARLY beam & column sizes via rules of thumb, from span and floors. For rough planning — not a structural calculation.
Advanced — rules of thumb▾
Beam height ≈ span ÷ factor; width ≈ height × factor. Adjust if your team has its own reference.
Early estimate — not a structural calculation
This is an early estimate based on common rules of thumb, NOT a structural calculation. The truly safe sizes/values depend on load, soil conditions, and seismic risk at your site, and MUST be calculated by a certified structural engineer (also a PBG permit requirement). Do not build structural elements based on this calculator alone.
Early size estimate
Need genuinely safe structural sizes?
Leave your contact and a Luxury Art engineer will help calculate structural dimensions & rebar for a PBG permit. Free initial consultation.
How this rule of thumb works
Rule of thumb, not a calculation
This estimate uses common rules of thumb: beam height ≈ span ÷ 12, width ≈ half the height, and minimum column size by number of floors. It's a planning starting point, not a load analysis result.
Span drives beam height
The longer the span, the taller the beam needed to avoid deflection. So a 6 m span beam is clearly taller than a 3 m one — but final figures always come from an engineer's calculation.
Columns follow floor count
Ground-floor columns carry the load of every floor above, so multi-story buildings need larger columns. The minimum-size table here is adjustable, but it's not a substitute for structural calculation.
FAQ
Frequently asked questions
What beam size for a 2-story house?
As an early estimate, beam height is often taken as about span ÷ 12. For a 4 m span, beam height ≈ 35 cm and width ≈ 20 cm (written 20/35). This is only a rough estimate; the truly safe size must be calculated by an engineer per the load.
What column size for a 2-story house?
As a practical starting point, columns are often 20×20 cm for 1 floor, 25×25 cm for 2, 30×30 cm for 3. These are common minimums, not a calculation result. Truly safe columns are determined by structural analysis by a certified engineer.
Is it safe to build based on this calculator's sizes?
No. This calculator only gives an early estimate for planning. Correct beam, column, and foundation sizes depend on load, span, soil condition, and seismic risk — and MUST be calculated and verified by a certified structural engineer, and are also a PBG permit requirement.
Why might the result differ from an engineer's calculation?
Because rules of thumb ignore many factors: the actual load magnitude, material type and grade, structural configuration, and seismic load. Engineers compute all of these in detail, so results can be larger or smaller than a rough estimate.
After knowing the estimated size, what's next?
You can use this estimate to compute rebar and concrete volume in the related calculators. But before building, consult Luxury Art so dimensions and reinforcement are calculated by a certified engineer for permit and safety purposes.
Structure & Early Estimates
Other calculators you might need
All free, no signup, and every calculation runs on your own device.
Luxury Art — Structural & Architecture Design
You have the early estimate. The structural calc needs an expert.
The calculator here is only an early estimate — decisions on structural size & strength must be calculated by a certified engineer, and are also a PBG permit requirement. Luxury Art provides certified structural & architecture design, professional cost planning, and design-build & construction management.
Architecture Design
Floor plans, elevations, and working drawings as the basis for structural calculation.
Certified Structural Design
Structural calculation by a certified engineer, ready for PBG permit submission.
Professional BoQ (RAB)
A detailed, realistic budget plan to keep your project's cost under control.
Design-Build & Construction Management
Construction and supervision by an experienced team, on time and to specification.
The initial consultation is free with no obligation. We help map out your design, structure, and permit needs.