Building Moving and Demolition (C-21) · Lesson 1 of 6

Estimating the Weight of a House You Are Going to Move

"Estimating the Weight of a House You Are Going to Move" is lesson 1 of 6 in the Building Moving and Demolition (C-21) Learning Hub. It opens with "Why the Weight Number Comes First" and works through 5 short steps, then a worked example you can check yourself against.

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Steps in this lesson

  1. Why the Weight Number Comes First
  2. The Code Rule: Use Actual Weights
  3. Count Only What Leaves the Foundation
  4. Measure the Right Area for Each Assembly
  5. Add What the Table Misses, Then Convert to Tons

The worked example in the course applies this lesson to a realistic job in 8 steps, starting with "Subtotal and allowance".

What you'll be able to do

  • Explain the main idea of "Estimating the Weight of a House You Are Going to Move" in plain language you can use on the exam.
  • Apply this step with confidence: "Count Only What Leaves the Foundation".
  • Apply this step with confidence: "Measure the Right Area for Each Assembly".
  • Apply this step with confidence: "Add What the Table Misses, Then Convert to Tons".
  • Test yourself on the worked example and the quick-check quiz inside the classroom.
Moving Weight Takeoff: 1,600 sf HouseHOUSE ON ITS FOUNDATION (ELEVATION)ROOFceilingwindowwindowinteriorwallsEXTERIOR WALLSFLOOR SYSTEMfoundation - stays in the groundOnly what leaves the foundation is liftedTAKEOFF (assumed unit weights, psf)Floor system1,600 x 9.515,200Ceiling1,600 x 5.08,000Roof (surface)2,041 x 816,328Exterior walls (net)1,280 x 1114,080Windows160 x 81,280Interior partitions900 x 87,200Incidentals1,600 x 1.52,400Subtotal64,488 lb+ 10% allowance (cabinets, fixtures)6,449MOVING WEIGHT70,937 lb70,937 lb = 35.5 tons to lift, crib, and carryCBC 1606.2: use the actual weights of the materials of construction (psf values here are example inputs).Roof area = plan area x slope factor (4:12 pitch: 1.054). Wall area is net of window openings.CC
The diagram for this lesson, exactly as it appears in the Learning Hub.

The first steps of this lesson

Step 1: Why the Weight Number Comes First

The CSLB C-21 Study Guide lists "Determining weight and structural integrity" as a core step of building moving, and every later decision hangs on it. The weight sets how many lifting points you need, the rating of each jack, how many crib stacks and what ground pads they need, and what the dollies and truck must carry. Guess low and you overload a jack or a crib stack; guess high and you overbid.

Step 2: The Code Rule: Use Actual Weights

CBC Section 1606.2 says that for design the actual weights of the materials of construction shall be used, and that where definite information is missing, the values used are subject to the approval of the building official. Translate that to a move: build the weight from real material data (manufacturer data sheets, the plans, the engineer), not from a rule of thumb for "a typical house". Every psf value in this lesson is an example input of the kind you would pull from those sheets; the code supplies the rule, not the number.

The remaining 3 steps, the worked example and the quiz are in the course. This is a preview. The full lesson, with the step-by-step explanations, a worked example and a quick-check quiz, is inside the classroom.

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