401 - TRACE 700 geometry from OpenStudio

Here's a quick run-through of the course! The ability to quickly draw the building in OpenStudio will change your life! Once you sign up for the full course, you can see the exact steps, plus receive the files for download.

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Welcome to the Openstudio to TRACE 700 webinar presented by energy-models.com. I’m Bob Fassbender, many of you already know me from my other courses. In this course, we’re going to draw for TRACE 700 in 3D using Openstudio. After this course you should be able to draw a building in Openstudio, use the main functions of Sketchup, export and import a gbXML file from Openstudio to TRACE 700, and also understand gbXML functionality.

So the question is, why draw the building? When we announced this course we actually got some questions saying, “Hey, why is this our job? We’re not exactly in the business of drawing the building, we already get this in Revit MEP.” But, having been in the industry awhile I know that the process from Revit MEP is not perfect, and often times requires a lot of additional work. I’ve found that necessity being the mother of all invention, this is a faster way for me to create the model myself, and I imagine that would be true for other building simulators as well. The other advantage is that you get to see your building: one of the top complaints in TRACE 700 is that you cannot see when you enter the geometry and therefore you really don’t know what you entered. Also, you can’t show what you entered to your clients. So with this methodology, you can see the building yourself, and show the building to clients. The other benefit is that you also get to learn openstudio while using TRACE 700. I think openstudio has a pretty promising future, and you might as well learn openstudio just in case you ever want to migrate to an engine like energyPlus, which openstudio does work with.

So how does this process work? We have a few slides to go through. I know everyone wants to jump right into Openstudio and look at this, but I do want to cover some of the process first because there is, unfortunately, one bug. To start the process we have to draw the building in Openstudio, which is what will do once we are done with the slides. Then, we are going to export to gbXML, which stands for “Green Building XML.” Finally, we are going to take that export and import that into TRACE 700. There is nothing new about importing gbXML into TRACE, the problem is that it’s been rather unsuccessful. Openstudio is essentially energy-modeling software so by drawing the energy model in energy-modeling software, the import into TRACE 700 makes a lot more sense. And then of course, we can finish the model in TRACE 700, something which we already know how to do.

So, gbXML is what again? XML is just a common way to transfer data. It looks like programming code if you have ever looked at code. Usually you can double click an XML file and it will open in your internet browser. As we mentioned, “gb” just stands for “Green Building.” So, Green Building XML has been around for awhile now. It’s an attempt at collaboration across software platforms. So, originally XML was probably from Revit to other software platforms. It can import and export much more than just geometry, but we are just going to focus on the geometry today because you will find that there is enough work to do there. I joke that the G is for gradual xml because the question that I have received many, many times is if gbXML actually works. The answer is, of course it works. In theory it works really well. The problem is that, not to insult any architects who may be here, but it does require collaboration with architects. We learn energy-modeling as engineers and now we want them to learn part of what we do and there is a little bit of trouble there. In my experience, it really equates to do it yourself, which is a bit of a slow moving vehicle so far and thus I’ve started doing this my own way and I found that it’s much, much faster.

So, let’s look at Sketchup. You’re aware of Sketchup, which started out as Google Sketchup and got acquired by Trimble so it’s now Trimble Sketchup. You can still download Google Sketchup for years from a number of sites. I believe you can still also download it from Trimble, but they probably won’t continue to offer that option. There is a free and paid option. The free option works with Openstudio, so you can always use the free option with all currently released versions of Openstudio. The paid option has some additional features. In this tutorial, I’m actually using the older version of Google Sketchup as opposed to Trimble Sketchup. The main reason I’m doing that is that the terms of use are more flexible and are more open for commercial use.

Then we get to Openstudio-- they are actually two separate programs. Openstudio is a program that runs in Sketchup. It’s a free plugin that you install after you install Sketchup. It’s made by NREL. The really neat part about Openstudio in my opinion is that it’s open source. If you are into code you can actually access the code and you can actually partake in making some changes to it, which I think is pretty neat knowing some code. In fact, when we get to this bug, I did try to look at fixing that my self, and I just don’t know enough c++. So, setting this all up is still cumbersome. You have to install Sketchup, EnergyPlus, and Openstudio so it’s three install to get this all going. It actually used to be more. It’s getting better. If you use OPenstudio as a whole, as a single package energy-modeling software, that’s getting much better as well.

Here, if we look at a completed building, this is what we are going to model. After we draw this, we will bring it into TRACE 700. I wanted to start by showing the completed building because when we draw it won’t look like this at all. You use a plugin in Openstudio to export to Trace, and you export the gbXML model. There is a bug, as I mentioned, and for those of you that would like to know when this bug is fixed, I did email the folks at NREL and they thought this could be fixed without too much trouble. Basically, when you export in EnergyPlus it doesn’t need this data, but in the lower right here where the arrow is pointing, that is what TRACE 700 reads. When you export from openstudio it does not export the area. If you use carrier hap it actually requires the area and the volume. It was made known that the volume is a bit harder to export and that makes sense when you start considering domes and other complex shapes. But I believe you can override that in other software. So, here if you wanted to know when this bug was fixed you just open the xml file and look to see that this area is here. So, in layman's terms right now Openstudio exports the gbXML but does not calculate the room area. It can and should be fixable, but the trick that I found is that it does export the roof area. And that’s what we can exploit.

If we consider TRACE 700 and 3D, this is why we can exploit this. Trace 700 has no inherent 3D geometry. Anyone who uses Trace probably knows this. We can enter a wall as 100 or 10 by 10, Trace considers it to be the same thing. Trace also does not know where the rooms are relative to each other. You can make thermodynamic arguments if you are an advance Trace 700 user, but it does not have the rooms in 3D space and therefore does not know where they are relative to each other. So, essentially, if I took that completed building and I broke up all the floors and we imported this into Trace, it would be equivalent to this in Trace provided we do a few things the same.

This slide is really important to understand that even though this is totally different in energyPlus or in eQuest, this would probably cause trouble, but in TRACE since it doesn’t know where these rooms are relative to one another and we typically don’t model partitions for similar spaces, this would be the same as this whole building in Trace. So, that’s the entirety of the slides and now we can get into Sketchup.

I preloaded Sketchup just for simplicity’s sake. We want to do a crash course on Sketchup here, and Openstudio. So right now I have several things installed. Google Sketchup, Openstudio, and Openstudio does require energyPlus install. We are not going to be using energyPlus. There are actually a few other things that I’m signed up for to have this whole process but you only need those three things to do what we are doing. Now, I do have on the side here, under the view, and Toolbars, I have the Large Toolset made available. When you use Sketchup you have this toolbar, but this bar here, these are Openstudio tools, these two bars here. We can actually move these around, I like to leave them side by side but you can drag and move this to this next bar, but I like it the way it is.

When using Sketchup you’ll want to use a three button mouse having a scroll wheel and a clickable scroll wheel at that. If you click the scroll wheel you get this spinny tool called the orbit tool, and we can move around and by default, Sketchup always starts with a person at the origin. Her name is Susan. We can delete Susan, but I actually refer to her at the start of this process because she gives us a reference for scale. We will get to that in a minute.

We have this orbit tool and if we use the shift key and use the mouse it allows us to pan. We have a tutorial on youtube INSERT on getting started with Sketchup. It’s five minutes and I’d recommend watching that to be comfortable with working in Sketchup. Primarily we need to know the orbit tool, shift + orbit tool to pan, and the toolbars, that these toolbars are Openstudio and these are Sketchup. Don’t be intimidated by all of these tools. It’s like an analogy my friend made about an airplane. When you see the control board for an airplane, it’s overwhelming, but really you don’t use all of the controls all of the time. These tools serve a purpose but most of the time we are working with twenty of these buttons tops. Each of these buttons is associated with a keyboard shortcut. We have these in the tutorial, but the primary one we are going to talk about today is R for rectangle, M for Move tool, we’ll get to those in a bit when we start drawing.

Ok, so you’re ready to start drawing in Sketchup. We’re going to learn the rest of the functionality as we go. We’re in Sketchup, but Openstudio is actually a separate program, which can confuse some people so it takes a moment to understand. It’s a separate program within Sketchup, so we are never going to save a Sketchup file but we will be saving an Openstudio file. We have to get started in Sketchup first. This is the sketchup menu, trust me on this for now. One cool thing about Sketchup is that I have these screenshots from eQuest, if you recognize them, they are screenshots instead of plans because if you don’t have the paid version you may not be able to import every kind of CAD file. Take a screenshot and import it. If you know the dimensions, thats really all you need. We are going to start with the basement. I kept this file pretty simple for demonstration and we don’t have much time. We’re going to start with the basement, and you can see when you move it around that’s why it’s nice to have Susan in the frame for reference. I’m going to put the corner right at the origin and then I’m going to scroll out and shift and move this over and notice that I can still move this in the meantime. One of the neat things about Sketchup is that you can perform other functions while you are in the middle of another function, such as scaling this image. And the long wall on here is 278 feet, the upper left wall. And if we just go by the size of Susan we can get a guess on if it looks right. I’m blatantly guessing right now, obviously that is not good enough. So, just using the orbit tool to get a better view of this. And there is the tape measure. We need to measure this to see how close of a guess I got. 178’. So this is 200 ft 10 inches, we’ll call it 201 feet. So I take my calculator and it’s 278.8 feet divided by 201 is 1.387. This is different every time, so I actually did have to do that on a calculator right now. Notice I’m still in the measure tool. If you hit escape, you can always quit what you are doing in the middle of the action. Right now we are still in Sketchup. What’s nice about Sketchup is that you can undo your functions so you can also hit ctrl + z to undo things. I will tell you when we go to Openstudio mode, it looks quite seamless but we are actually still working in Sketchup, which is the best way to start. So we have the factor and we go to the scale tool, which is this button. You can take a good guess and say that Scale is probably S and that’s in fact the shortcut. Click this corner to scale it, I just clicked it. In the lower left, I’m not going to move my mouse now or you’ll see that the picture will shrink. It says 1.00 in the lower left, and what I need to do is type in that factor we calculated earlier, 1.387 and hit enter. Now, if we measure this we have 277 feet. We can mess around but I’ll leave it at that because it’s close enough. What we need to now is trace this with the pencil tool. You’ll run into trouble in approximately 6 lines. It does snap to the image slightly but sometimes you just have to zoom in. I clicked and I could type in 278.8 feet to get that exactly right. Type in 278.8 and you have to remember to put it in feet, because otherwise it will assume inches and we’ll end up with a tiny line. So we hit enter, and now you can’t really see it because I’m drawing on a black surface, but these green dots are the existing line. I’m going to hold the shift key and just move this. Now I’m going to click on the green dot and I’m just going to trace the rest of this, the exterior, on the green dot again. What’s nice is that I can scroll in between here because it’s not snapping the way I want it to. I’m trying to do this quite quickly so we could do this more accurately with a picture of the CAD file. When we draw that, when we fill it in Sketchup automatically makes a surface, which is nice but now we can’t see our rooms that we want to trace. So what we do, and this is a key feature to know about, the x-ray mode will work. So, I’m going to ignore this room and this little closet, we’ll just have two thermal zones in the basement. Now I need to zoom in to snap. If we undo x-ray mode we can now see that we have our floor with two zones. Now what I’m going to do, I’m going to bring in the next floor. This building is six floors including the basement. Several of them are identical to save time. Let’s go to import, and select buildings 1 and 2. I’ll click this again and what I’m going to do here since I took the exact same screenshot, I can basically line these up and I can measure, but I’m actually not even going to bother measuring right now and you will see why. So, I’m going to look at this from the top and select the select tool. When you want to select something in Sketchup, if I drag this around this entire frame, we select that and now what I want to do it move this. And move is the M key as we mentioned earlier, so hit the move button or type M and now I will hit the ctrl button. If you notice, when I toggle the control button the plus symbol disappears. I’m going to drag this right over to match the other surface. I’m going to highlight these lines and delete them. It’s really important that we keep the footprints identical because I’m going to stack these later. Of course, if they aren’t identical in real life we still want to keep certain walls identical otherwise the building will look crooked. Now we’re going to go into x-ray mode. And I need to complete the zones on this building. So I’m going to grab the line tool, the pencil button, and zoom in. You just want to get to all of the vertices to define all of the zones. Click to take an existing vertex and then drag to another one and finish the line. The red dot means that we are on an edge. Then we are on another edge. We can look at this, we can toggle back and forth from x-ray mode, and we have what equates to our ground floor or our first floor depending on what country you’re in. If we looked at the other images, they were essentially all identical, and we are going to keep them as such for practical purposes. Often you have an identical footprint, and you just need to redo the zones. SO, what we’ll do here is try to look at this directly from the top again. I actually made a mistake here but it will be good for the demo. I missed just a slight chunk of this and it’s not highlighted, which means it’s a mistake. The reason that I was trying to cut it close is that I did not want to highlight the background image, because if I highlighted that then it would copy that as well. So, now I’m just going to hit the M key and the plus button, the control button to get the plus button, and right here, this is what we want-- we want where it shows the green dotted line. Otherwise, I’m moving this maybe in 3 dimensions when the line is a black dotted line. So right here, I’m moving this, and they are nice and flat and on the same plane. I’m going to hit control again and copy this and move it along the red axis. Notice, I’m giving a little bit of room in between these. Pan over, there are some other ways that we can do this as well. If you aware of floor multipliers, if you use TRACE, you could also consider doing that. But we want to be able to see the entire building, so we are going to draw all of it. If the zones were different, on one floor vs. the other, we could just take this line and delete it or something like that and then draw the zones, we could delete any of the lines and redraw them. I’m going to leave it as it was. Here, we have our view from the horizontal, we can adjust the camera with the orbit tool which is in our Youtube tutorial.

Now we have the basement, the ground floor, and floors 2, 3, 4, and 5. What we want to do, is this is all in Sketchup right now. We need to know the height of each floor, and in this case it is different. Really there are three buttons right here that are important. One is create spaces from the diagram. If you had curved walls, you’d want to draw the curved walls in an arc. IF we talked about making domes or other things we would do that later, but anything that could be raised vertically and still keep it’s curve we would want to do at this point.

So, let’ look at the basement floor. The basement is 11.2 feet tall. Take the select tool and select the basement. Right now, I’m going to select the openstudio model, I’ve already saved it earlier so I’ll save it again. If you don’t save it right away, it will prompt you to save. Openstudio asks you to save periodically. When we are working in Openstudio, it’s very, very important to periodically save. You can use Ctrl + Z in Sketchup, but it doesn’t work very well at all in Openstudio. So, we are still technically in Sketchup even though we’ve saved the Openstudio file. We should also probably save the Sketchup file as well.

I’m just leaving it untitled, but it’s nice to save in case the program crashes. Highlight this without highlighting the background image, and click create spaces from diagram. If all of the floors were the same height we could do all of it at once, but several of them are different. 11.2 and again, make sure you put in feet or it will default to inches. That’s why it’s nice to have Susan in the picture. She can get in the way, but if you zoom in you can see that it makes sense that its 11.2 feet. If she was towering over the building, ii would be obvious that we had entered inches. So, now we have the ground floor. This is 14.1 feet. And then the rest of these are all 13 feet. So, we can take all of these and now we have all of our spaces defined. You would be able to actually export a gbXML file and it is similar to what TRACE understands, but it’s not correct because part of the whole purpose of this is to get the windows which are often difficult, as well as any other additional geometries. I should caution that shading devices have not yet been tested, but I don’t think it would work because of the way that shading works in TRACE is much different than in Openstudio as far as defining the options.

What we can do, we have 42 rooms at this time, is take this and export this into TRACE and that’s part one of our workaround. The reason is that by default, these are all their own building and thus every room gets its own roof. That’s the workaround we’re using to get the room area. We get the roof area but not the area of the room, so we can go to plugins, Openstudio, export to gmXML. Phase 1.xml and now if we wanted to open this in TRACE, and though this is a big TRACE file we’re using it for one simple step.

Open TRACE, go to import, gmXML, and save that to the desktop as phase1.xml. Open this. The fact that we are doing this directly before we did the Trace file, it will also put the Trace file in this desktop folder. We can actually define these other items in Openstudio but in my opionion, it’s better to do that in templates in Trace anyway. In my experience, don’t check the use name as space identifier. Now, it imported, and here we can look at all the rooms and one of the things when you import this is that it defaults into metric units. Switch that at option, units, switch to English. I’m leaving it in metric for now. We have all of our spaces unnamed. If we scroll through here, all of them have a roof and none of them have a floor area. Ideally, we would take these two fields and switch them to put this above except for the spaces that do infact have a roof. That’s the next part of our model in Openstudio. One of the things that you want to do here is go into excel and go to the component tree view. Look at the roofs, the length, width and the space name. I’m going to copy that and say that it is from phase 1. Close out of Trace. Go back into Openstudio. You got that, right now we basically have six separate buildings, Trace brought them all in and brought in exactly what you see, so we have all the roofs. Now we get to the fun part. I do want to note that as soon as the area functionality is fixed, this step can be skipped. Until that area portion of the gbXML is fixed, this is the only workaround. It’s a good way to start like this anyway because it’s much easier to draw this way.

The next thing we want to do is stack these. If you try to stack anything in Sketchup or Openstudio it’s a tad difficult. I want to point out that we are working in Openstudio. The second that I clicked create spaces from diagram and brought up the basement floor, that was an Openstudio model. If I draw a little block here and use push/pull, and draw a building. You can see that it’s white, the default color for Sketchup. The default colors for Openstudio are brown and beige, so you know that we are working in Openstudio inherently when you start to work this way. Working in Openstudio, if we want to do that before we stack these, if I drew something on the wall here, I’m drawing in Sketchup so I would need to double click. This is actually a window and we know it’s a window because we can see through it, but I had to doubleclick to tell Sketchup I was trying to work in openstudio.

Now, I’ll delete that out of there. So, if I drew the rectangle on here, and this is how we will do this later, it’s appears to be a window but we can’t see through it. The benefit of doing it this way is that we can make this a window later, but in the meantime to erase it I’ll hit ctrl z, and remember, ctrl z doesn’t work in Openstudio. Go to save as, save as a 3D stack. To stack buildings in Openstudio, we have to highlight the individual portions. Right here we have everything selected. This is very important-- we are going to use the move tool. You can try to move this but you will spend all day and night trying to align it if you don’t do it this way. Click on this vertex, and now all we have to do is click on the vertex we want it to snap to. If we want to stagger it, vertex to vertex would snap. If I were to click out in the corner somewhere, you will ˆndeed move it but it’s hard to tell where it’s moved to. As soon as you switch to another angle you may see that it’s 2 miles away. It’s hard to move in 3 dimensions with the mouse, which is why it is easier if you snap vertex to vertex.

If you are familiar with any of this process, you might realize that there is a major thermodynamic mistake going on right now. That’s because all of these have roofs, and right now it doesn’t know that just because this building is stacked, the ground floor doesn’t have a roof, the basement doesn’t have a roof. It still thinks that each floor has a roof, and that’s ok.

We’re going to move this again. See, this is why I did not make it any more complicated. When we originally brought this up, we could have made it into four floors. But then we wouldn’t have gotten the area from the roof. So again, this whole process was about the bug. If you remember when we clicked create spaces from diagram, and all the floors were the same height. We could have had it into one floor and enter multiplier four and that would have projected it.

See, I made a mistake there. Since I was using the conventional move tool, I could do a control z. There’s probably a different way to fix it.


I’m going to look around to make sure I snapped it to the correct vertex, and we have one more floor to stack. Use the move tool or the M key, and now we have all our floors stacked. The problem is, every one of these floors has a roof. There’s actually a fix to that. So save this again, before we move on any further, we can get rid of these images. What we want to do, is we have the windows defined, and we have these top four floors that are all identical. We need to start drawing windows, and if you recall, the way to draw the window directly in Openstudio is to select the zone and then the face. Now, we can directly draw the window. But, there is something else we can do. We can draw the window onto the space and then use this button, project loose geometry. So, loose geometry is just geometry that is in Sketchup but not in Openstudio. So, when we drew one of those windows earlier but couldn’t see through them, we were actually drawing the window in Sketchup and Openstudio had no idea that it existed. Project loose geometry button brings that’s in. The reason that it’s so helpful is that we can start the drawing using Sketchup functionality to copy windows and make things much faster, whereas those tools don’t work in Openstudio. You will see what I mean in a minute. We already used this button to create spaces from diagram. We can set attributes, and this other button, the surface matching is what’s important. So we can go to surface matching, and we want to intersect the entire model. Before I do that, what we can do is render by boundary conditions, which is a way that the surface is exposed to the sun and wind it’s one color, if not it’s another color. We can look at this now in x-ray mode and all of the surfaces are the same color. So again, I went to render by boundary condition, and then I went to view model in x-ray mode. We can highlight this all and edit the highlighted section, or we can use this button and intersect the entire model where it doesn’t worry about being highlighted and automatically does it for you. So that told this where everything is located relative to each other, so there aren’t two surfaces on top of each other touching, it made them into one. Now, we want to do the surface matching, which intersected the surfaces so that it would recognize floors touching a roof and correct it to make it one plane, locating floors, partitions, roofs, and model them in different colors. If we undo x-ray mode, the exterior is still all of the same color because it’s all exposed to the sun. Save now. Select a basement wall, and then there is this inspector tool. The basement of course is buried, so what I want to do is take this inspector tool, open it and tell us the surface that we clicked. Whatever we clicked, it will bring it up when we click the inspector tool. What I want to do is label this as no sun, no wind, and it’s all exposed to the ground. We can close this and you can see that it actually changes colors when we are rendering by the boundary condition. So this is essentially the boundary condition that says no sun, no wind. I’m going to make sure that we clicked just one wall, and use the inspector again. This won’t take too long because we only have a few walls in the basement. Let’s go to only no sun. It changed a different color, which means no sun but still exposed to the wind. You can see that the inspector tool actually changed the color immediately. Ground, no wind. Now you can see that that color changed as well. We have four more walls. Inspector, no sun, no wind, exposed to ground.

If you could not select a specific surface, you can actually spill through here and just highlight the surface as we go. I think it’s easier to double click, but it’s your preference. When I switch it to ground, the color also changes. Set it to no sun and no wind. Here we go. So we render as usual and you can’t see any difference. It autosaves automatically but it’s not a bad idea to use version control with save as. The building is now missing windows, we need to draw some windows on here and things do speed up from this point. I selected a zone, we need to go to the inspector, rename these spaces if you wish, and you can go through here and see on the right which space its selecting. it’s pretty self explanatory. You will need the space names to be the same as the model where all of the floors were separate building, so make sure you keep those consistent between models.

Now we want to add some windows to the building. ,We’re going to use the rectangle tool as opposed to doing it directly in Openstudio. Zoom in. Make sure that it says “on face in group.” If I start this and say really make a mistake, hit the escape button to cancel your action. Now you can see it snap to the corners, but we want to leave some room. This window is 155 ft by 5.9 ft. Again, Trace is just going to see and import this window so the exact placement isn’t important other than for looks. hit the m key and the ctrl button, drag it down, hit the ctrl button again, make sure the line says same face and is a parallel line. You can sometimes accidentally move this and drag it out one foot, making it no longer a window. We have the same windows for these four floors. Get the rectangle tool again and look in the lower left and you can see the dimensions approximately so you know whether to enter the width or the height first. I sometimes forget myself and use this to check. 146.25 feet comma 5.9 ft’ return. You can see that it’s sort of a window, but to Sketchup only at the moment. We’re going to bring them all in at once instead of one at a time. Hit control, and see there, I’m moving this incorrectly. It’s bad because it’s a rectangle floating in space. Hit escape, control again, so this is it on the face even though we moved it. It just so happens that the angle I was looking at was similar to the green axis, so I just rotated it slightly. Now I move that. We have windows on these walls as well, but I’m skipping that step for now. Windows on these you would do the same process again. Here at the bottom we have some custom windows and what you have to be careful about is make sure that you don’t snap the window to the full wall, at least so I have been told. So this was 14.2’ and we have a 13’ window, so be careful that we don’t make it too big otherwise we’d have to move it again. So we go here and get close to the edge. We can see that it’s almost 13’ and we have some room so we know that it’s ok. We have 82.44 ft’, 13’. Here we have another window that is 13’. You can see that I snapped the edge and it’s 14’ so we have enough room. This is 45’ by 13’. Scroll out to look at it, and there is another window here. 61.3’, 5.9’ and I almost forgot to put in the foot symbol, which would have defaulted to inches instead of feet. Leave all the windows on the side. No windows on the basement. And then we have the windows on the back here and basically we’re just going to repeat this process a few more times.

If you recall, all of these floors were 13’. This one was 14.2’ and the basement was 11’. They all have the same windows. You can see that I have an overlap here, and that’s bound to happen eventually. Use the move tool and you can see why I try to avoid correcting with move tool, because we are snapping this where we don’t want to move it. We want to move it along the face. Hit the M key and control key to copy the window and place it on the other floors. You can experiment with making these walls 100% glass but I’ve heard that it causes some bugs in Openstudio to EnergyPlus. However, if you move into Trace I don’t see why Trace would not read that, but it may not because then it might not have a wall to identify with the window, which could be a potential problem with the xml file.

Right here, we’re going to make a couple of more of these so we are diligent with our building’s appearance. This was 202’ by 5.9’. Hit M, ctrl and make copies on all the floors. We have one more set of wall before moving into Trace 700.

Here we go. You can rotate the building here, but you can also rotate it in Trace. Here we have the building, and if we exported this it would export the building without windows because the windows are in Sketchup but not in Openstudio. We’ll do a little demo here. Notice how you can’t see through these windows. What I want to do is project the loose geometry, and project all loose geometry. You can do this by selection which would be helpful in a larger model. You can see through these windows now. They are transparent, which means they were successful modeled as windows within Openstudio framework itself.

Now go to Openstudio, export the gmXML model. This is our final geometry. By no means done, this is just our geometry in Trace. We save, and then open Trace 700. Go to Import, gmXML, go to the desktop where we saved the file, final_geometry.xml. Again, we could actually set these up by launching Openstudio, but that defeats the purpose of using Trace in my opinion. So we have our 42 rooms, and now you can see that there is no roof or extra walls. Earlier, in the other model, there were walls in this space but in reality they were partitions. As we scroll through here, we have a lot fewer walls and a lot fewer roofs. The problem is, the area is incorrect. We could have skipped that initial model and go in and put your areas entered into here, but the way I would build this in Openstudio is the way we did this anyway. I only took the extra step to export to gbXML and copy the roofs into excel. Now we can go into the component tree view mode, and there is a bit of a caveat here that I want to show you. I set this up where it worked automatically if you followed these steps. We go to rooms, and you see we have the floor length and width for the room and it’s 0. The first space is space 125, then 117. So we want to make sure these spaces match up. If we had made more edits its possible they wouldn’t match up, which is why we would have wanted to name the spaces ahead of time or it would be nearly impossible to match it up. Again, if they fix this in the future in the export process or one of you knows c++ and can help them do it, it is open source. I’m going to show you a little trick, maybe some of you already know this. This is our final model. So what we could do is what’s called an hlookup, click the final space, and then highlight the table for phase one. Basically, right now the hlookup is saying you are going to look up the space under 125 in this region, lock it in that region, and the next number is the number that we will return which is the row index number, and then false to find the exact match. Sometimes it doesn’t work for whatever reason. This will work pretty smoothly because they happen to all be in the same order from model to model. But since sometimes they get mixed up, HLOOKUP is a useful tool. Drag this down, and make sure to lock in the number. Then we’re going to return to 4. Drag and drop that.

Now you can see that really, we ended up with the exact same thing. But for scenarios where the spaces do not match, HLOOKUP is what you want to use. And now we should have the areas matching up. Go to project navigator and save this. Of course, we need to select the weather location because otherwise it will choose La Crosse as the default location. For now, we have the geometry set up. We would want to double check the areas for sanity's sake since we are using a workaround that bases it off of the roof. We can switch to English units at this point. So here we have floors with their areas. This one happens to have a roof. And then we can cross reference this with our existing Openstudio model to make sure it is correct.

Now that we have the geometry, some of you may be thinking that you could enter the areas in Trace just as quickly. Remember that’s assuming that you are using room multipliers. If we had changed these ever so slightly, there is no way you could do it all in under an hour. This process should only take about 30 minutes. The question is, where do we go from here now that we have the geometry. Let’s look at one of these rooms. Notice that it brought in the height of the wall, which is good. But, the floor to floor height and the plenum height are brought in from the template, which is good because we can just override that input in the template itself. So, if you recall, several of these spaces are different so we have to go through and setup templates by floor. For demonstration here, let’s assume that 13’ wall by 13’ floor height and 3’ plenum for all the floors. This will automatically assume that there is a 3’ plenum where we never actually had to draw a plenum in Openstudio, which have been a bit more tricky and wouldn’t export cleanly into Trace. You can draw plenums in Openstudio if you are going to EnergyPlus, but that’s a different story completely. From here, I’d always recommend to people to set up their templates first. We could give our spaces names, we could have done that in Openstudio, but now we are free to give our spaces names again within Trace. I would probably recommend giving them names in Openstudio but it would have made our tutorial a bit boring. On your own time it is definitely worth the effort. I’m going to save this as our final project. Notice that the Sketchup model is still untitled. If we open the Sketchup model you would probably get it tied into the Openstudio so you would get the Openstudio mode. If we had anything saved in Sketchup and just opened the Openstudio model, the items from Sketchup would be gone. In general, you pretty much want to concern yourself with saving in Openstudio.

One other thing to demo, but first let’s talk about moving on from Trace. Moving on from Trace you can enter your systems and plants as normal. The main thing is setting up the templates and going through room by room to setup the templates. Most of the templates, like the construction template, you will only have two or three. In many buildings it’s the same throughout the building. You want to setup the construction types as well, but we don’t have it specified here since we are focused on the geometry. You can set this up and if you look, all of the values in red are tied into the templates, so when we change it, it will automatically change the construction types as well. We can already do all of that within Openstudio, but it doesn’t tie into the gbXML specific geometry.

I’m going to close this. I paused the screen there because every time I close Sketchup it crashes, and I didn’t want you to get scared-- it’s an issue specific to my computer. So here I am in a blank Sketchup file again, and let’s see exactly what we could do. Let’s say we have a space, and this is in Openstudio, and we have a curved wall. Now, we can do this by taking the eraser tool and exit out of that. And so we can mock this up now with our curved wall by selecting the area, and create spaces from diagram. Now we have this nice curved wall segmented by Openstudio. We have quite a few walls here, about a dozen, but that’s not terrible. Sometimes when you do this in Revit you get over 100. Now, one of the common things that people may have trouble with or questions about is making a domed roof or something similar.

Stay tuned on our update for curved geometries.

Course Version Information:

The Trimble Sketchup tutorial uses the following versions:

  • Energy Plus Version 8.1
  • Trimble Sketchup version 14.1
  • OpenStudio 1.5.0 
For the folks still using Google Sketchup, the tutorial

For either course, the downloads will work the same.