Designing a Supply Air System: Step-by-Step Guide in Revit and BP

Welcome back to the CAD Teacher VDCI video course content for the BIM 321 course Introduction to Revit and BP. In the previous video we went ahead and got our second floor return air system dialed in, so let's go ahead and get our supply system dialed in. So I'm going to go back up here to DUC.

There we go. Make sure you're using an 18 × 12, so again if you need to just pull down and change it to 18 × 12, and please make sure your system type is supply air. If it says return air right now, go ahead and change it to supply air.

I'm going to go ahead and start drawing my duct in now. So I'm going to go ahead and start here. I'm going to go ahead and come out just a little bit, come up along this wall, and then once I get to this gypsum board roof, I'm going to come over and I'm going to run on the other side of the hallway.

I'm going to go all the way down until I need to, line up with that register there, and bring it over, then escape this end of the chain. I'm a little close to that wall, so I'm going to select it and use my directional arrows to just move it over slightly. Now I know that there's one thing going on.

I know that this duct and this duct are both colliding here, because remember this is at 10 feet and this is at 10 feet. So what we're going to end up doing is we're going to be moving our return air system up like we did on the previous level to kind of keep the same look and feel. I'm going to adjust these just slightly.

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I'm going to bring this a little bit closer to the wall here so I can have room for some fittings here. I'm going to take this guy and bring it down just a little bit. Perfect.

So what I want to go ahead and do now is I'm going to go ahead and split this here. So I'm going to go SL for split and I'm going to go ahead pick about here, pick about here. Instead of having to drag it away, I know I'm just going to get rid of it.

So I'm just going to get select this like that and delete it. We need to go ahead and draw ourselves a section so we can kind of see what's going on. So I'm going to go ahead, go to my section tool, start here, pick, drag down and there we are.

I'm going to go ahead now and double click on my section, had to go into that section. I'm going to go ahead, go WT to window tile and there we are. The other thing I want to go ahead and do is let's go ahead and change our detail level to medium so we can see the full duct.

Let's go ahead and change our line style to wireframe. Now right now in this view, it's kind of hard to see exactly what's going on here. So I'm going to go ahead and pick the duct system that I want here in my plan view and if I come over to my section view and click, you can see now that I have that selected.

I'm going to go ahead and change the offset of that to 11 foot 2. Enter and there it is. The really cool thing and the reason why I did this this way was because of the fact that because all of these systems are interconnected, all of these tabs are connected to this main. When I move this up, it moves everything up which then allows me, the flex will adjust accordingly.

It's really nice and really simple and makes life very, very easy. Now I need to go ahead and zoom in here and I'm going to draw in my 45 degrees. Draw duct 135.

There we go and I'm just going to go ahead and trim them together. Perfect and there we are. The next step I need to go ahead and do is I need to go ahead and start populating in my taps off for my ducts.

Now remember for the supplier system, we are going to have VAVs. We need to find common areas where we can bring this VAV in and then be able to tap that out to all the different supplies. So I'm going to go ahead and use a 14 × 14 duct for these larger rooms and then we'll just use our standard 12 × 12 for the smaller rooms.

So I'm going to go to my mechanical or I'm going to go to my ducts, excuse me, change my size to a 14 × 14. Go ahead and find that 14 and go ahead and change your offset to 10 feet. I'm going to come in down here and I'm going to go ahead and tap this guy off here.

Bring it over about there. That's fine. We'll use our VAV.

Now the one thing I forgot to do here was to change my system type. As you notice, I changed everything else but I didn't change my system type. That's why I have the blue and the pink.

I don't necessarily need to redraw it. I can just hit escape to end my duct command, select that and then just change the system type here to supplier. You don't really want to move forward without doing that.

You kind of want to keep those at the same time. I'm going to go ahead and zoom out. I'm going to go DT for duct.

I'm going to go ahead and start about here. Bring this guy over to about here. There we go.

Again, I forgot to do it again because I changed it here manually but I did not change it in the actual command. So let's go ahead and change it to supplier here. I'm going to hit escape, select this guy and change it to supplier also.

I'm going to go ahead now and go back into my duct command DT and I'm going to go ahead and change it to a 12 × 12 because we're going to be doing the smaller ones now. There we go. I'm going to go ahead and tap this off here, bring it in, tap this off here, bring it in, tap this off here, bring it in, tap this off here, bring it in, tap it off there and bring it in there.

Perfect. We have all of our locations set for where we want our VAVs to be. I'm going to hit escape.

Let's go ahead and change this one down here at the very end to be a 12 × 12 also. So I'm going to just change that width to be 12 × 12 and it will automatically put the transition in for us. One thing that we don't really want to have is we don't want to have that transition in the wall.

That's really not going to work well in the field. So I'm going to go ahead and select this and I'm going to go ahead and I'm going to slide it back so that transition is out of the wall and there we are. Now I'm going to go ahead and start populating in my VAVs.

I want my larger 12-inch VAVs for these larger rooms and we'll use the 8-inch VAVs that we used downstairs here. So I'm going to go to my mechanical equipment. I'm going to change to my 12-inch VAV.

There we go. Change my offset to 10 feet and I need to go ahead and rotate it around so my inlet's on the correct side. There's that.

Come up here, place that one there. Okay. What I'm going to go ahead and do now is I'm going to bring my section down to make sure I get these to line up correctly.

So I'm going to select this, bring it down, RO for rotate, turn it 90 degrees. There we go. I'm going to go ahead and I want to draw a little piece of duct out of here.

So there. Perfect. I'm going to go ahead and use my match attributes to make this duct and this duct the exact same.

So I'm going to go MA, pick here, pick here, perfect. There it is. I want to go ahead and align those two, AL for align, pick here and pick here.

Since they are already aligned in the floor plan, I can just trim them together. TR for trim, pick there, pick there. Perfect.

I'm going to go ahead, come out of here, bring this out. Let's go ahead and change this back to a 14 × 14. I don't necessarily need a 17 × 14 here.

And bring it out and turn it down. Perfect. I'm going to go ahead and tap out of this now to get to these other registers in the same room.

So I'm going to go duct. I'm going to go 12 × 12. And I want to use that 10 foot and three eights.

I'm going to draw here. There we go. And I'm going to go ahead and draw here.

And then I'm going to go ahead and bring this guy and just slide him over a little bit to be closer to the duct. Perfect. Let's go ahead and also change this guy to be a 12 × 12 also.

So I'm going to take it from that 14 × 14 to 12 × 12. Perfect. Everything's coming along together nicely.

Now I know that these two are clashing right here. This is at 10 feet and this is at 10 feet and three eights. So I'm going to go ahead and select this.

Drag it over. Do my rotate. 90.

There we go. In my plan view, I'm going to go ahead and split this. So SL for split.

Pick on the edge there. Pick on the edge here. I don't want to remove this piece in the middle so I'm going to drag it back.

Drag it back. But I will remove the unions. And then I'm just going to go ahead and move this up to 11 foot 2. There we are.

I'm going to go ahead and draw in my 45 degree angles. And I'm going to go over a little bit this time. So what I'm going to end up doing is moving those back.

Draw a duct. 135. I'm just going to go ahead and select them and then use my directional arrows to move them back to where I need them to be so I can get over that duct efficiently.

There we go. Then just trim it all together. TR for trim.

Pick here. Pick here. Pick here.

Pick here. Remember you want to click on the things that you want to keep. Perfect.

I can go ahead and connect these in with their specific flex duct. Pick here. Right click.

Draw flex duct to there. Select here. Right click.

Draw flex duct there. Select here. Right click.

Draw flex duct there. And there we go. Got everything all there dialed in perfectly.

Awesome. Let's go ahead and work on our VAV up here. I'm going to go ahead and bring my section up so I can get it correct.

Rotate 90 degrees. Just move it just a little bit. Perfect.

I'm going to go ahead and draw a little piece of duct out of this. I'm going to use my match attributes. So MA.

Pick here to match that one there. And I'm just going to align them there and there. I'm going to go trim.

Pick here. Pick here. There we go.

And then I'm going to go ahead and draw my tap out. Going to change it to a 14 × 14. Take it out.

And actually on this one I'm going to go ahead and actually take it off at a 45. One thing that we want to do is be nice to the air. If you make more 90s it's going to create a harder system for you.

And there we go. I'm going to go ahead and go back to DT. 14 × 14.

Let's go ahead and make that 12 × 12. And then tap out this guy here. I'm going to go ahead and now connect those with my flex.

Select here. Right click. Draw flex duct.

There we go. Select here. Right click.

Draw flex duct. There we go. Perfect.

Now we just need to go ahead and populate our VAVs on this side here. And we're almost done with the mechanical system for the second floor. So I'm going to go to my systems tab.

Mechanical equipment. Going to choose my VAV 8 inch. Change my offset to 10 feet.

It's already kind of correctly facing the right direction. So I'll place it about here. And I'm going to leave that one there.

Let's get this one situated first and then copy it down so they're all in the same location. So grab my section. I'm going to bring it down.

And again, we call this a working section. It's a very important part of our MEP. Because we are dealing with that z-axis, we want to be working on both plan and section view.

So I'm going to go here. Draw a little duct out. There we go.

I'm going to go MA for match attributes. Pick here and here. And then I'm going to align it.

1. Pick here and here. The one thing when we're working with these VAVs is that we need to make sure that we draw enough ducts so we can leave room for the fittings.

So make sure you're drawing at least a decent sized portion, at least 1 foot 6 to 2 feet so you have room for your fittings there. Since this already has, and then I'm going to go ahead and draw this little guy out here. So I'm going to make this a 10 × 10.

There we go. Now, since I have that VAV all lined up and everything and everything's good to go, I'm going to go ahead and copy this guy now. So I'm just going to drag a window over it.

I'm going to go up to my modify bar up here and go copy. I'm going to use this endpoint here as my copy point. Drag it up and line up with that one there.

Again, I have my multiple option checked. There we go. And we may need to go back and align them.

That's perfectly fine. Perfect. I'm going to grab this guy and bring it back a little bit because it kind of got in the way.

Now, one thing that we need to do to align in this plan view is we need our center lines, right? Well, let's go ahead and change our visual style to wireframe. But as you can see, our center lines did not show up. Remember in the first floor plan, we had to go into VV to turn on our center lines.

So let's go VV. I'm going to go to scroll down and find ducts and turn on my center lines here. Apply.

Okay. And there we are, good to go. I'm going to go ahead now.

I can go ahead and trim this together. Perfect. I'm going to go here, AL, make sure it's aligned first.

Trim. Pick, pick. I need to align these two, here, here, and then TR for trim, here, and here, AL here and here, TR for trim here and here, AL for align here and here, TR for trim here and here, AL for align here and here, TR for trim here and here.

There we go. So, let's go ahead now and connect all of our system together. So, I'm going to go here, right-click, draw FlexDuct to there.

And there we go. I'm going to go ahead and zoom extents, Control-S, save the file. I'm going to go ahead and stop this video here.

In the next videos, we're going to be taking all of our lines up this shaft, tying them in together to an air handler unit that we're going to create up on the roof. See you then.