Proper Placement and Scaling of Roof Slope Symbols in Eighth Inch CAD Drawings

In this video we are going to work on our roof slope symbols and we're going to look at our dimensions for this view. In this case we want to make sure our insertion scale is set correctly for our blocks.

This drawing is going to be at 1 eighth inch, which is a common scale for roof plans, and so our scale factor is going to be double that of a quarter inch, so 96. I'm going to come over and make sure I change my uniform scale to 96, and your angle might still be set to 270. I'm going to reset this to a zero degree angle.

Now when we bring in our slope symbol we're going to have it come in at an appropriate size for eighth inch drawings. So I'm going to hit insert, make sure that you go to the blocks folder, drafting, and find slope arrow. You can see that this slope arrow is pointing to the right, so when I hit open I'm going to come down into the garage, use my crosshairs to align roughly with the middle of the garage, and I'm going to place it here.

Now this is the slope itself, and this is a 5-12 slope, which means that for every 12 inches of run, the horizontal distance, it goes up five inches. So this slope is a fairly normal slope for a lot of, this slope is fairly normal for a lot of the range in the United States, but you'll see steeper slopes in colder climates and shallower slopes in warmer climates. 5-12, and I'll hit okay, and our first symbol is placed.

Before we start to copy this symbol around into other places in the drawing, let's mirror this into the right location for our other views. So I'm going to start by selecting this object, mirror, I'll start in the middle and go across to the left side of the roof, click to place, and enter because we want to keep both objects. We also need to mirror one down into this portion of the roof, so again I'll pick the same object, mirror, and in this case I'll grab this midpoint and show it that 45 degree angle and click and enter, and now we have the arrow facing down.

You can see that this one's a little low on the roof because there's no roof vent here, so I'll click it, hold CTRL, and click my up arrow to nudge it into place. There's no exact science to where to place these slope arrows, just make sure that they're obviously representing the whole slope, so you wouldn't want to place it off to one side, like over here. Find the center of mass and try to place it there.

Finally we need a slope arrow pointing up, so I'll pick this, mirror, you don't really need to choose a specific location, but I'll still grab the middle here and send it across, and enter, and before I do anything else to get this one in the right place, let's copy these around to all of the remaining roofs. You'll notice on our handout that we are not placing slope arrows on these two roofs. We don't need to do it on tiny roofs like this, but depending on your office, make sure you're doing the best practice for your CAD standards.

Let's start with the down arrow. I'll select it, click the grip to make it hot, right click copy, this one goes here, again I'm using my crosshairs to align with that vent above, try to center it there, click to place, and one more down here. Again this one's pretty tight, so I'm going to click right here, escape, escape.

Let's do the left, right click copy, this one's going to go over here, this one's going to go here, and escape, escape. Let's do the ones facing to the right, right click copy, this one again I'm aligning with the vent, and that's the only other arrow facing to the right, and here I'll right click copy, and I'm going to place this one again, aligned with the vent, but I'm going to try to avoid that dashed line for the wall, so it's a little tight, that's okay, and then this one goes here, shift right click and choose none, so that I don't accidentally grab a midpoint snap or something like that, just barely fits, and then this one I'm going to escape, escape, escape, and just move. Now it's too tight, I'm going to make sure that the 5 over 12 is centered in the space.

You'll see on the handout that we can do something to this arrow and this arrow to make them fit a little bit better. Before we edit any of our arrows, let's go around our roof plan and make sure that all of our roof sections are covered with an arrow. All of these roofs eventually get to the gutter, so we'll start over here in this gutter, it's connected to this whole roof shape, so there's an arrow, and I'm just going to go around and visually check, as I work my way around the gutter, that each of these roof slopes has a slope designator.

You might say that all roof slopes are at a typical scale, but it's very common to see roof slope arrows like this on your entire drawing. Now we're going to talk about bursting a block. If I come into this arrow and I want to shorten the arrow and shorten this part of the arrow, if I go ahead and hit explode, it is going to break that block into the attribute and the geometry.

The attribute will be exploded into a text object, but will not remember the instance value we had associated with the block. So I'm going to hit control z to undo, select this block, and type in the word burst, b-u-r-s-t. Burst is only used for exploding blocks, and it makes sure to use the instance value, in this case 5 colon 12, instead of exploding the block into its component parts.

Also, you'll see that it did create individual geometry objects, but it kept them on the a roof vent layer. If you're ever working with a block that has attributes, make sure you use burst instead of explode. Now I want to stretch the arrowhead back and this line up, so I'll go s enter for stretch.

I'm not grabbing any end points in this diagonal line, so I can go right over the enter to say I'm done. I'm going to bring this down, and you'll notice I'm going about 12 inches, so I'll type 12 enter, and I'm doing that just so that I can also stretch this end point the same distance. S enter, just grabbing that end point, enter to lock it in, coming up 12 enter.

Now this is a little tight still, so I'm going to grab all of these in the selection window, and control click up two clicks, there we go. Let's do the same thing with our other kind of tight slope arrows. I'll grab this one, burst, s enter, I'll bring this back 12, and I'll bring this up 12.

And one more time, we'll do it down in this part of the roof. Burst, enter, s enter for stretch, and this one I'm only going to bring up six, and bring this one down six. Zoom extents, control s to save.

Now it might be wise to create a dynamic block that lets that arrow length be variable depending on where you're placing it, etc., but in many offices this is the best practice. Make sure that these are all on the same layer, make sure that they're all controlled with the same visibility, and if we ever need to update this text, we can still go in and double click the text. It's just m text instead of an attribute on the block.

Escape, escape, zoom extents, control s to save. Now in this case, we didn't put these slope arrows on the right layer. We can see that we accidentally left these all on the A roof vent layer.