Last week I talked about solar bidding as an art form. In art, as with most things, there is a range of concrete and abstract approaches to art. Estimating is no different. This week we are going to start with the most concrete: Take-offs.
I like to say estimating can be broken down into two methods: Averages and Take-offs. This is a bit of an oversimplification. When building a house the first step is to create a solid foundation. One can liken Take-offs to the foundation: if done wrong you will be compensating for the entire project. But if you do it right everything will go smoothly.
Sometimes called stick-estimating, takeoffs involve writing down each task (or item) no matter how small, then writing each labor action required to accomplish task and assigning a number of labor hours. Because of this, it’s arduous and slow going. A lot of resources get tied up in trying to do full take-offs.
In essence Take-Offs is the task of creating a Bill of Materials. You just include Labor too. In the solar industry take-offs can take the form of anything. Take the roof work. A takeoff list for materials would be something like:
- Probing drill bit
- Pilot drill bit
- Quantity of 5/16” lag bolts
- Quantity of 5/16“ washers
- Quantity of standoffs
- Quantity of flashing for standoffs
- Quantity of sealant
- Flashing nails
- Shingle knife blades
- Quantity of rails
- Quantity of ¼” bolts
- Quantity of ¼” washers
- Splices
- Quantity of weebs
- Quantity of weeb lugs
- Quantity of weeb splices
- Quantity of L-brackets
- Quantity of ½” bolts
- Quantity of ½” washers
- Quantity of End clamps
- Quantity of End clamp bolts
- Quantity of Mid clamps
- Quantity of Mid clamp bolts
And the list goes on and on. You may notice that we have not included electrical, unless you count the Weebs. Same with modules. This list was only for a flush mount, composite shingle roof, for that matter. You can then imagine how the list gets longer and longer the more parts a system has. Imagine writing up 30,000 tasks for one project and spending the time to assign a price and labor for each. The benefit is that at the end of an estimate all materials have been tallied and every task has been thought out. Then, if won, the project is a breeze.
Weaknesses of Take-Offs
Though it might be obvious at this point, I’d like to highlight the weakness of Take-offs: they are time consuming. Sitting down and counting up every little part takes a lot of planning. The entire system has to be designed before take-offs can be effective. The strength of Take-offs lies in the follow-through, because it really forces the estimator to walk through the whole system. The numbers do the work, so judgement becomes less of an issue. When I’m faced with a completely new task and I have no idea the price, I will do a take-off to understand the pricing. Usually it’s a modified version of takeoffs, specifically Unit Pricing. But we will get into Unit Pricing next week.
Help the whole community by leaving a question or comment here, on Facebook, or shooting me a message on Twitter. Your questions and comments will invariably help others to understand too as the comments and answers will invariably cast a different light on the same subject. I look forward to talking more about estimating! Shoot me a message if you have a particular topic you want me to address too!