Manual Load Takedown with Pen and Paper

2025-08-21

Manual Load Takedown with Pen and Paper

Understanding load paths and being able to quickly, reliably, and accurately carry out a load takedown calculation is a fundamental skill for every structural engineer. The ability to trace loads through a structure — from roof and floor areas down to beams, walls, columns, and foundations — underpins both manual checks and software-based analysis.

At the early stages of a project, you don’t want to open a full analysis package just to check whether your walls and foundations are in the right ballpark. A quick manual load takedown, literally with pen and paper, is often enough to test the scheme, confirm tributary areas, assess load paths, and build confidence before committing to more detailed calculations.

In this post, we’ll walk through how structural engineers undertake a load takedown by hand for a simple one-way spanning structure, and why it’s still a useful skill even in an age of powerful design software.

1. What is load takedown?

A Load takedown is the process of examining a structural form and determining how applied loads are transferred to the supports, usually at ground or foundation level. It involves starting at the top of a structure — such as roofs or floors — and working downwards, calculating how loads pass through beams, walls, and columns until they reach the foundations.

In practice, load takedown means assessing how each element contributes to carrying and transferring loads, and arranging supports in a way that is both efficient and economical while ensuring stability.

A load takedown can typically be broken into three key steps:

• Assessment of load paths — identifying which elements support which loads (e.g. floor → beams → walls → foundations).
• Calculation of tributary areas — determining the loaded widths and contributing areas for floors and roofs that define the forces on supporting elements.
• Reduction of loads to supports — combining tributary loads with self-weight to calculate the reactions at each vertical element and, ultimately, at the foundation level.

2. Sketch the structure

Begin by sketching the supports and span directions of the floor plan on a drawing (even a simple PDF printout).

• Identify the span direction of each floor.
• Mark the supports (walls, beams, or columns).
• Determine the relevant loading for each floor — typically dead load (self-weight, finishes) plus live load (imposed loads per code).

The following is a simple markup of a house floor plan.

Simple structural markup of a house floor plan

3. Calculate vertical loads on a support

Pick a vertical support from your sketch and identify which floors span onto it. Work from the highest floor down to make checking easier.

Convert floor area loads into line loads on the supporting members at either end of the span.

Example: One-way spanning floor, span = 6 m, imposed load = 5 kN/m², dead load = 2 kN/m².

Loaded width to supports = span / 2 = 6 / 2 = 3 m

Applied area load = Dead + Live = 2 + 5 = 7 kN/m²

Line load to supports = Loaded width × Area load = 3 × 7 = 21 kN/m

Note: This assumes a simply supported one-way span. That’s usually sufficient at early design stage or for simple structures.

Example hand calculation:

Structural line loads calculated by hand.

4. Continue level by level

Work down through each storey until you reach the foundation. By the end you should have the total line loads supported by each vertical element.

5. Add wall or column self-weight

Calculate the self-weight of the wall or column and add it to the total of the floor loads. This gives the reaction at the base of the support.

6. Repeat for all vertical supports

Repeat the process for every wall or column. This builds up a full picture of the load distribution through the structure.

A spreadsheet can help with this task as there can be significant calculation repeats required:

Structural foundation line loads calculated with a load takedown spreadsheet.

7. Keep it simple, but consistent

A few tips for manual takedown:

• Always sketch floor spans and tributary areas to make checking easier.
• Note assumptions clearly (e.g. one-way spanning slab, uniform loading).
• Don’t chase decimal precision at early design stage; round sensibly (e.g. 132.7 kN → 133 kN).
• Remember the goal is a sanity check, not final design forces.

8. Why still do this by hand?

• Speed → Early-stage design needs quick feedback.
• Clarity → Sketching tributary areas shows where load paths work (or don’t).
• Communication → Simple diagrams are easier to explain to colleagues and clients.

Even when you later use FEM or advanced software, being able to do a pen-and-paper load takedown keeps you grounded in first principles.

9. Next steps

If you find yourself repeating these hand calculations for every project, it may be time to look for tools that automate the repetitive parts. That’s exactly why we built: LoadTakedown →

A lightweight web app that lets you sketch structures directly on PDFs, assign loads, and get tributary load results instantly.

LoadTakedown home page showing a complex load takedown project.

Manual load takedown is a fundamental skill for engineers. Keep it sharp, but don’t be afraid to let software speed up the process when projects get bigger.