Building Accurate Construction Estimates Using a Cost per Unit Sheet and Spreadsheet Formulas

All right, welcome back. So what we are going to do now is we are going to grab our unit costs and we're going to input them into this sheet and really build out what our cost is going to be for this project. So you are all given a resource that lives with the rest of the resources for this course, and the title of it is just going to be called the cost per unit sheet.

So I'm going to pull it up right now on my screen, and this is going to be exactly what you are going to have to reference as well. And you can see on this cost per unit sheet that it is sorted and filtered in a similar way. We have our spec sections, our subjects, our cost per unit, and you can see, as I was mentioning earlier, for certain specification sections like wood framing, for example, we have a lot of different items on the project that may have different cost price points to them.

We're not able to just have kind of one blank unit cost for wood framing because floor joists might have a different cost than glulam beams, which might have a different cost than wood posts or exterior sheathing. So that's the reason why we had to organize the estimate the way we did. And that's the reason why we want to show both the detail page that lets people know what the unit costs per each different type of material is, as well as the total sheet on the front, which lets somebody know this is the total cost for all of the wood framing, all of the concrete on the project.

Let's go ahead and start to transfer these items over into our estimate sheet here, and let's see, the best way to do this probably is going to be to just put these two sheets side-by-side and do a little bit of copy and pasting here. So let's grab our initial estimate sheet and let's put these two side-by-side. On most computers, that is really just being able to grab the document and swipe it up to the top of the screen, and there are usually split screen options there for you to be able to do this.

If you have multiple monitors up, you could put one sheet on one monitor and one sheet on the other monitor. Um, those are just some of the simple ways to get this side-by-side. All right.

Learn Construction Estimating

• Nationally accredited
• Create your own portfolio
• Free student software
• Learn at your convenience
• Authorized Autodesk training center

Learn More

And let's go ahead and drag our cost per unit column on our estimate sheet over closer to the subject, just so we can view it all in one pane here. Great. We've got our estimate sheet and we've got our cost per units, and we're just going to do some copy and pasting here.

So structural concrete, all of our concrete items are going to be at that hundred dollar per unit costs. So let's just go ahead and paste that in. And we can just hold control C and we can actually press control V to extend that hundred dollar cost per unit down to all of our structural concrete items.

Next up, we've got concrete masonry units, the CMU at the foundation wall. That is going to be a $10 per unit. We're going to throw that in here.

Metal railings. We've got two metal railings items here. Those are all going to be 45 each.

Just going to paste that in there. All right. Wood framing.

That's really where we have some work to do. So glulam beams is going to be the first one here. We see that we have glulam beams on our lists.

Let's go ahead and just take that price point and input it into here. Next step, we've got wood posts. We've got the four by six first and then the six by six.

We'll take, copy both of these four by six on top, six by six on the bottom. 75 and 80. Excellent.

Now we have all of our floor joists here. Our floor joists going back up to row five on the cost unit sheet. That's going to have a cost of $60 per unit.

Now we still do have a little bit of work to do on these items, as these are ones that we noted that we have to buy a certain amount, we did measure the length of these, but we also needed to know the count to know how many actually have to order at that length. We'll come back to these, but we do have a little bit of massaging to do to those numbers. Next, we've got exterior sheathing, exterior sheathing.

That is just going to be this $8 per unit figure here. All right. Now we've got plywood floor sheathing and we have many those, so we can do an easy, just drag in.

We'll copy that over from the detail sheet and we can just right-click copy, hit shift, go down to the last item and hit paste. Great. We've got all of those input there.

Two by four interior stud wall is our next one. Take this $10 per figure here. See if we can do a bulk paste.

Nope, didn't do that right. We'll just copy that one again, hit shift, take us down to two by four. Go ahead and populate that one in.

Next up, we've got two by six exterior stud walls. Do a copy, paste that, just drag it down. Hardwood base.

Those are all going to be $750. Go ahead and paste that in and let's drag that one all the way down to show in different ways to kind of get data in quickly here. Two by six composite siding.

So all of our composite siding items are going to be this $350 cost point, easy way to go ahead and take that and then just drag it down. Reselect that one, drag it down. Composite siding.

There we go. Membrane roofing here. Let's see what we've got for CMU waterproofing.

We've got $8. We've also got $8 for the other membrane roofing item. Let's go ahead and paste that.

Then we can select on that one and drag it down. We've got sheet metal flashing, the 24 gauge galvanized, as well as the standing seam metal roof. And it looks like the 24 gauge galvanized is a $12.50 cost figure here.

And then the standing seam metal roof is going to be a $15 item. Take that and we'll go ahead and drag that down. Jumping into our doors here.

What cost figure do we have? We've got all of our doors at a $200 per item. Let's go ahead and throw the door number in there. And I apologize if this is a little bit tedious to get through all of this.

We just really want to do a thorough double check and just make sure that our costs per unit are all getting applied to the correct items. Oftentimes in other estimating software, there may be like a database of cost items, and if your company uses Bluebeam often, then you could have a lot of different tools that are already built out and they could have unit costs applied to them. So this is definitely not always typically what you'll have to do.

Sometimes you may even have access to like an RS means or a cost database where you could just import in cost figures. But for the purposes of this exercise, I figured we'll just input some of the costs that we've populated in here and kind of show you what it looks like to really formulate one of these at the end. But let's keep moving here.

So casement windows, all of our windows are going to be $250. Go ahead and put that in. We could drag that down.

Stucco finish, $1050. Put that in there. Drag that all the way down.

Exterior sheathing is up next. We'll get the cost figure of $6. Put that in.

All right. Gypsum ceiling sheathing, also $6. We can take that all the way down.

Interior sheathing, also $6. Take that down. Tile flooring is up next.

We've got $12 there. After that, we've got hardwood flooring, which is at $15. We'll take that and put it in.

Next up, sheet carpeting, $1250. Paste that in. Drag it down, $3.

Bathtub enclosure and sink and toilets here. Actually, it looks like we can just do a bulk copy and paste for maybe the rest of these. Let's go ahead and hit copy and then hit paste.

And let's double check. We've got bathtub at $125, sink at $55, toilets at $85, outlets $10, $10, $10 for switches, recessed can fixtures $35, $35. All right.

Those are all of our costs per unit. Now we can go ahead and get out of our cost per unit sheet, fully maximize our estimate, and really get back into it here. Now that we have a cost per unit in here and we've got a measurement, let's go ahead and make a formula to get us to our total cost.

We're going to say the measurement and the measurement unit times the cost per unit is going to equal the total cost. We're just going to make a quick formula and it's just going to be measurement times unit cost. It's going to get us the total cost.

You can see that some Google Sheets and even Excel might suggest a formula for us. We can go with that formula and then we can also auto fill it or simply drag that cell down to the bottom of this table and it will auto fill in for you. So there we go.

You can see that we have auto filled our formulas all the way down. And now what I'm doing is just making a total cost row all the way down at the bottom here. And let's see if we can get the sum of all of these.

Sum of F2 to 141. Excellent. We're going to go ahead and press TAB on that and that is going to be the cost for our total project right here.

We can go ahead and format this cell and we can make this a currency item. We'll be able to find that on the toolbar. We'll say this is going to be a currency.

So there we have the total cost for our project with all of the items broken down on this detail sheet. Now, I did say that there's a little bit of massaging that we have to do here. So what we're going to do now is just comb through this sheet really, really quickly and make any minor changes that we may have to make.

One of the items was our floor joists here. So in the floor joists, we said that these are going to be each figures because we have to order by an individual joist, not necessarily by the length. So what we're going to do is we're going to swap the lengths that we measured with the counts of the joists.

And that's how we're going to come up with the total cost here. So this one is going to be 10 joists and it's going to be at 20 feet each because that figure was just 19.7. So there's going to be 20 foot lengths. Next one, we've got a count of 18.

We're going to change that over to 18 and we're going to say that these are also going to be 20 foot lengths. The reason why we're doing this is because to come up with the length of the joist, we obviously had to measure it on the screen. But we had to do our own kind of mental math because these are just these are not all shown on the plans for us to be able to click and count.

This is where we would have to take the total length of the room, divide it by the on center spacing of each of the joists. So that's the only reason why we have to do a minor massaging here. So the top one, 16 each, and that's a 22 and some change.

So these are going to be like a 24 foot length for each of those joists. Awesome. We've made that revision that's made some changes to our totals over here.

Going down further, let's just see if we see anything else that jumps out at us here. We've got exterior sheathing and we know we did that in a linear instead of in a wall area, which is OK. We were measuring kind of the wall assembly there.

Plywood floor sheathing all looks good, stud walls all look good, base is all going to be in linear footage, that makes sense, siding is all in square footage here, waterproofing, membrane roofing, membrane roofing at the parapet here. So it looks like these two items we should get into square footages instead of linear footages. So let's actually go do a quick look in our estimate and see what depths we held for these and we can convert these over to square footages.

So going back into our estimate here, let's pull up blue beam. And when we pull up blue beam, we wanted to look at our membrane roofing. We had two items to look at.

We had our CMU waterproofing and we had our membrane roofing at the parapet. So membrane roofing at the parapet, we've got 176 square feet. Let's go ahead and type that in.

Membrane roofing at the parapet, we've got 176 and we'll just take this unit and put square feet in there. And then CMU waterproofing where below grade, let's go back to the estimate again. CMU waterproofing where below grade was going to be, let me expand this, 132 square feet.

Awesome. Let's just put that in, 132 square feet. OK, great.

So, so far we've made some changes to the floor joists. We've made some changes to the membrane waterproofing and roofing. Let's keep going down here.

You see square footages for all these counts for all of our doors and windows, square footage for stucco, linear footage for exterior sheathing. That's OK. That's how we measure the wall assemblies.

Chips from ceiling sheathing, square footage, interior sheathing. Again, we measured wall assemblies with triwall both sides. Got tile flooring, square footages, all these are square footages and all the rest are counts.

OK, excellent. So this is going to be our detail sheet and this is the output that it should be looking like. And what we're going to do next is just jump into our cover sheet and we're going to finish formulating that cover sheet.