How to Estimate the Cost of Building a New Home

This will serve as a help guide by providing some tips and techniques for estimating the cost of building a new home. As an expert residential estimator there are many things to consider before you begin estimating.

Construction estimating can be difficult and it does require a high level of accuracy and detail. It also requires good math skills and a little geometry knowledge. It requires the ability to read and understand construction drawings and details and how they are applied. Basic construction knowledge helps and being familiar with the local building codes.

You may want to enroll in a construction estimating course at the local college or technical school. Another option is to purchase an estimating manual from your local bookstore or go to estimating.org which offers online courses and has a bookstore.

One of the rules that I have learned along the way is the old saying, "measure twice cut once." Whenever I do a takeoff or an estimate I always follow this rule in order to help minimize mistakes.

What will you need to put an estimate together?

You will need a notepad, a calculator, an architectural scale, and an engineering scale. These are the basic tools you need to put an estimate together.

Architectural & Structural Drawings
Now you are ready to open the plans and begin to review them. The easiest thing to do is look them over and get a feel for the basic building concept. You should get familiar with the information that is contained on each sheet.

Most construction projects have a set of architectural drawings and a set of structural drawings. I will explain the difference between the two.

It is important that the plans are to scale and have all the required details and wall sections needed to properly estimate from.

What is typically included in a complete set of architectural plans? The drawings at a minimum need to contain the following sheets: a title/cover sheet, a site plan, a floor plan, a foundation plan, four elevations, a roof plan, an electrical plan, a sheet with a typical wall section, a sheet with the window and door schedules, and a sheet with the necessary building and architectural details.

The structural drawings are drawn by a structural engineer, not the architect, unless the architectural firm has an in-house engineer. Any interior shear wall or bearing wall is detailed on these drawings.

The engineer calculates all the uplift and bearing loads of the roof trusses on all the interior and exterior. After doing the calculations they determine which walls are shear or bearing or both and what is required to properly support those uplift and or bearing loads. The engineer will put a structural note on any wall that is bearing or shear. The note will indicate the sheet number and detail number illustrating how that wall needs to be built.

A load bearing wall for example could have a thickened concrete footer with two pieces of steel and the wall above it may need to be framed out of southern yellow pine versus spruce with special metal hardware. These should be highlighted on the plan so they will not be overlooked. Sometimes the hardware called out by the engineer is a special order and can take several weeks to get. So if you wait until the framing package needs to ordered and there are a two or three shear walls with special order hardware it could delay the construction.

You need to make enough copies of the architectural and structural plans for multiple subcontractors and suppliers bidding the job. To save you money, ask your architect and engineer to convert the drawing files to a PDF file. This will save you time as well and make it convenient b