Calculating Floor Joist Quantities for Guest and Music Rooms Using Architectural Sheets S3 and S4

All right, and welcome back. Now we are going to focus on doing some takeoffs on the structural wood members who make up the guest room and music room. We're going to navigate over to sheet S3, and we're also going to have some on sheet S4.

And what we're going to really start to focus on first is these floor joists here. We can see that in both the guest room and the music room, we have floor joists that are 11 7 8 inches. And the type is this TJ 1 over 360 floor joists, and they're at 16 inches on center in both rooms.

So how we are going to take this off is we're going to start in the guest room, and we're going to get the length of this joist. And then we're going to figure out how many of them there are, since they're set at 16 inches on center. We're going to do that for the guest room.

Then we're going to do that for the music room, and then we can move on to some of the other structural items. So first things first, let us double check our scale here. We can see that with sheet S3, our scale is one quarter inch is equal to one foot.

Let's jump over to sheet S4. In sheet S4, we can see the same thing. One quarter inch is equal to one foot.

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Now, we haven't really set the scale for these particular sheets yet. So let's go over and hit shift, and we'll click on both S3 and S4. We can go ahead and right click and hit set scale.

And when we hit set scale, you can just choose from this dropdown list. Now, I've already set mine to one quarter inch is equal to one foot. But all you would have to do is just navigate through this list.

Find one quarter inch equals one foot. Click on it. Hit apply scale.

And the way that you can confirm that it was applied properly is simply by looking over at the thumbnails and looking at sheets 23 and 24 and seeing that the scale is showing right there. So back to sheet S3. And let's go ahead and take off this joist.

We are going to just grab a length here. And we're going to do the length takeoff from arrow to arrow of this particular joist. We go ahead and do that takeoff.

And we're going to go over into the properties wheel. And we're going to give this a name. We're just going to call it exactly what it says on the screen.

We're going to call it 11 7 8 inches TJ1 over 360 floor joists. I am going to qualify that this is at the guest room because this is going to have a different length than at the music room. We've gone ahead and we've gotten that length.

Now, to determine how many of these joists we need to order, we can see that they are set at 16 inches on center. So let's go ahead and get the length of the entire room and then divide that by 16 inches. And then we will be able to see how many joists we actually need here.

So let's go from the outside edge here all the way down to the outside edge as well. And for this particular instance, let's go over to the properties bar and turn the caption on so we can see. And let's go ahead and zoom in here.

And you know, let's go back to the original one and turn the caption on as well, just so we can see that. So, OK, each individual joist is going to be about, we'll say, 20 foot long. And then the room, oops, sorry, I navigated away from the sheet.

Go back to 23 here. So the room itself is going to be 23 feet and two and a half inches. So let's go ahead and take 23.

And I'm just using my phone calculator to do some math here. We're going to take 23 times 12 to convert it all into inches. That gets us 276.

And we're going to add 2.5 to it. We have 278.5 inches total. We're going to go ahead and divide that by 16.

And we have 17.4. So let's go ahead and just call it 18 of these joists is what we need to order. So over in the properties in the naming, I will just say that let's just say count 18 for guest room. So that's going to be a quick and easy way to get the exact number of joists that we're going to use in this particular room.

And let's go ahead and in terms of specification section, let's just go ahead and throw this under 061100 wood framing. We're not necessarily going to distinguish between structural or just exterior wood framing. We'll go ahead and throw that on there.

And let's actually go back to one of those items here. Let's set this as the default because we're going to go into the music room and we're going to do the same thing. We've gotten our main structural joists for the guest room.

And let's go ahead and do our main structural joists for the music room as well. And it looks like we have a similar situation with a main joist running through the middle. And let's go ahead and get the length on that.

Okay, so we've got 19.8.5. That's great. And again, to figure out how many of them there are on center, let's just take the length of the entire music room. Start up there and we'll go down.

And we can see that it has us at 12 foot 5.5 inches. So let's take that 12th and let's multiply it by 12. That gets us to 144 inches.

Let's add that 5.5. That gets us to 149. Let's go ahead and divide that by 16. Again, this is just math that I'm doing on my phone off the screen.

And when we divide that number by 16, it gets us to 9.3. We obviously cannot have a.3 of a joist. We're just going to carry an extra one here. And over in this takeoff in the music room, we are just going to change it to the guest room.

Oops, sorry. We're going to change it to the music room. And we're going to say we count 10 for the music room instead of 18.

And let's change this title of music room as well. Great. We've done those two main structural joist items.

What I'm doing now is just deleting the length calculation that I've come up with here just to get that out of the way. And we have completed our two main joists. We know how many of them there are.

And we can go ahead and move on to some additional structural items now.