Short answer: No.
And that’s because you’ll use them incorrectly. They actually work just fine. It’s us pesky humans that muck it up.
I recently received an inquiry from a young couple that is hoping to buy land and build a home in Sonoma County, CA.
I shared a budget from a recently completed project that showed how a 620 square foot custom accessory dwelling added up to over $200,000 in work.
Here is his response:
“I was somewhat surprised at the cost — are the various online building cost calculators just completely off?
We don’t have land yet, but we’re weighing whether to buy land or buy a house on a large parcel, and how complex and expensive the process of building is will help us make that decision. (There are many of both options in Sonoma county.)
This potential client had used this online calculator: http://www.building-cost.net/CornersType.asp
The calculator looks impressive and the results are quite reasonable but it’s easy to miss the following costs: Permitting, impact fees, structural engineering, soils engineering, utilities, demolition/site clearing, driveways, sidewalks, site drainage and landscaping.
It is also REALLY EASY to select products and materials or quality that doesn’t match the actual tastes of the owner. That is probably the biggest cause of getting costs that are “way off”.
For example, you might say mid-range bathroom which means fiberglass shower and vinyl flooring in the calculator but it means custom glass tile and Kohler brushed nickel in your mind. When you go to buy that tile it will inch your budget up by several thousand dollars. Do this 20 times and you’re way out of line with the initial budget calculator.