This week we were exposed to estimating for the first time. I found this very interesting, because with estimating, you have to take a very complex system, break it down into component parts, and create a line item with a cost for the entire very complex system. The process is very similar to when my roommates and I created our shopping list for the week on Sunday Night. We want to decrease what we are spending on groceries for the rest of the month, so we decided to created a more detailed shopping list than we normally do.
We knew we could not just pull a price out of the air for the cost of food for the week (this is equivalent to guessing the cost of a building, when all you know is that you want a building), so we broke the week down into the different meals we were going to cook on which days, essentially the assemblies of a building. For our grocery list, we needed more detail so we could actually know what and how much to buy, because we can’t go to the store and buy tacos, and pasta dinner off the shelf. We then broke each of the assemblies down into the components, with quantities. Once we knew what we needed and how much we needed, we could estimate the cost of the entire purchase before going to the store.
Now we did not create a unit price table for our grocery list, but I recognized how useful it is, and how similar it is to our shopping list from Sunday night. We were able to jump strait to the unit price estimate, because the bidding was over, we knew who the contractor was going to be, we knew the project was going to happen (no one wanted to starve for a week), we just wanted to know what we were going to spend. On a more expensive and complex project, more general estimates are defiantly needed in the early stages. For example the owner needs to know early on, if they can even afford the construction in its entirety.