There are lots of ways to estimate the cost of your house. The reality is that most homeowners turned contractors have very little experience with estimating and have even less experience compiling numbers for labor rates related to specific aspects of the job. As a result, many owner/builder or owner-contracted homes go way over budget. With the right training and practice, however, even someone new to contracting can be successful. Here’s a quick tip for accurate estimating.
It’s important to realize that estimating is a blend of art and science and is something that takes a long time to completely master. That said, success can be had with the help of proper training and material use. One way to get insight into the estimating process is to use estimating books; however, their exclusive use can be a bad idea. In my experience, the best way to fully utilize these books is to set up a spreadsheet to help you with the process. With your construction drawings in place, you can create take-off sheets to help dial in the details of the job. A take-off sheet is simply a spreadsheet on which you write down all of the materials and their costs from a specific job.
Be sure to get as detailed as you can in the creation of the sheets. For example, when you are estimating the cost for the foundation of the house, the obvious things to price are labor, form boards, concrete and rebar. Items that can ruin your estimate if forgotten are things like concrete stakes, form nails, and other connectors. These things are often thrown into the “add a few bucks for nails” column, and the results are poor estimates. Breaking down the individual aspects of the job in finite detail will also help you build the home in your mind ahead of time, making the actual construction easier later on.
If your take-off sheets are really accurate, you can go directly to the suppliers and get material prices for each aspect of the job. This will give you accurate material pricing; however, estimating labor can be a bit more difficult without the help of professionals if you have never completed a similar job before. When it comes to labor, the estimating books are a great place to start, but keep in mind that the numbers in those books are based on professional contractors. You’ll need to adjust those numbers to reflect your labor skills.