A quantity take-off is a term used in
construction to mean that someone figures out how much material that they need
for a piece of work. Usually that means using
the drawings to come up with dimensions.
I have done a lot of scaling, which is warned against on the drawings
mostly to protect designers against missing something on their drawing. In Canada commercial building drawings
are typically in millimetres and the scale is usually between 1:100 and 1:200
at least on the buildings I deal with. I
have a ruler (a scale) and measure the various elements on the drawings to get
what I need.
At work I typically am figuring out how
much concrete I need. Concrete take-offs
are really easy. It is length x width x
height. You neglect the rebar as they
don’t take up much room. If the area
that you want to pour is not square you just make your best guess on square as
at the end of the day you will round up.
It is better to have a little too much than not enough.
When I am working on a project at home I
like to draw it out to visualize the project and to put some dimensions on the
piece. Then I take the pieces and put it
on a sheet of plywood or dimensional lumber, this then gives me the counts of
how much material that I need to pick up.
This goes for material other than wood, but I do not have as much
experience with those as well.
If there are a lot of components,
especially repeated components then I like to build an Excel sheet that will do
the math for me, just so that I do not make a mistake. I do this at work
frequently, especially because then I will need to issue a purchase order and
that sheet will show my work and justification for the purchase.
Share in the comments how you figure out
how much material you need for a project.
If you like what you have read, please subscribe to the blog, or follow
me on twitter at @bjshideler. Also, share this post with your friends on your favorite social
media sites.
Hi, I love math, so this post really appealed to me. I am a retired elementary teacher/librarian, so I have taught math. Volume and measurement are two of the skills that kids have so much difficulty in grasping. Thanks for a good post Best regards to you.
ReplyDeleteRuby aka Grammy
@Grammy - Math is very important. I always did well with it in school, but I never excelled in it in Engineering at University, so I was very relieved to only have to do volume and area calculations at work.
ReplyDelete