Optimize Hip Truss Designs

Before you begin, open Paragon Design.

Hip trusses have a flat top chord between two sloped ends. Trusses generated from a layout often need a few modifications, such as a heavier bottom chord on the hip girder, a dropped flat top chord for purlins or lay-in framing above, and verticals at the pitch breaks. This article shows how to draw a hip girder and make these adjustments.

Note

The example is a 24' hip girder with an 8' setback at an 8/12 pitch: 8' up at 8/12, 8' flat, and 8' down at 8/12. Distance fields accept values such as 24' or 1-1/2. Slope fields take the rise per 12 of run, so enter 8 for an 8/12 slope and 0 for a flat line.

Draw a hip truss

If your hip trusses come from a layout, open one in design mode instead and go to the next section.

Step 1 - Click Create and choose Component

You can also right-click empty space in the scene, or press Ctrl + Q, and choose Component. The Component Insertion panel opens at Basic Shape.

Step 2 - Under Draw a freeform profile from scratch, enter the span, such as 24' in Length

Step 3 - Enter the pitch of the hip, such as 8 in Slope, and press Enter

Under Profile Line, Distance is how far a line runs horizontally, and Slope is its pitch. Pressing Enter in either field adds a line straight away, the same as clicking Add Line, using the current values of both fields. Distance starts at 8', the setback in this example, so Enter adds the first top chord: an 8' run at 8/12 from the left heel up to the first pitch break. For a different setback, enter it in Distance first, then click Back Up to remove the line that Enter adds.

Step 4 - Enter 0 in Slope and press Enter to add the flat top chord

Distance is still 8', so Enter adds an 8' flat top chord, from the first pitch break to the second.

Step 5 - Click Close Profile

The first click adds the last top chord, from the second pitch break down to the right heel. The right heel matches the left one, so this top chord is also 8/12.

Step 6 - Click Close Profile again

The second click adds the bottom chord and closes the profile. The panel moves to Shape Details.

Step 7 - Click Next, then click Insert

The top chords are named from left to right: T1 and T3 are the sloped ends, and T2 is the flat top chord.

Upgrade the girder's bottom chord

A hip girder carries the jacks and hip trusses that frame into it, so its bottom chord is often a size up, such as a 2x6.

Step 1 - Right-click the bottom chord, such as B1 under Members, or right-click it in the scene

If the bottom chord is split into multiple members, multi-select them in the scene first. Then, right-click any selected member to change them all at once.

Step 2 - Choose Edit Lumber

Step 3 - Choose 2x6 for Dimensions

Drop the flat top chord

Dropping the flat top chord lowers it so framing, such as lay-in purlins or a lay-in gable, can run over it. The top of the chord then aligns with the plane of the adjacent sloped roof.

Step 1 - Select the flat top chord, such as T2 under Members, or click it in the scene

Step 2 - Click Edit Truss and choose Drop Flat Top Chords

Edit Truss is the pencil icon in the top toolbar. You can also right-click the flat top chord and select Drop Flat Top Chord. The Drop Flat Top Chords panel lists the chords to be dropped, such as "Dropping T2". If no chord is selected, click the flat top chord in the scene.

Step 3 - Enter the pitch of the roof that crosses the chord, such as 8 in Crossing Slope

Crossing Slope starts at the most common slope of the truss's top chords, here 8/12.

Step 4 - Enter the thickness of the purlins, such as 1-1/2 in Lay-In/Purlin Thickness

1-1/2" is the default, the thickness of a 2x purlin laid flat.

Step 5 - Check Supports End Of Lay-In/Purlin

Check this option on the girder where the lay-in purlins end. It changes how far the chord drops. The option is unchecked by default for trusses where the purlins run across.

Step 6 - Click Drop

Add verticals at the pitch breaks

A vertical web under each pitch break gives the dropped top chord a solid joint at each end. Make these edits directly in the scene. Member names change as you add and delete webs, so check the labels on your truss as you go. To learn how to add members and reference lines, see Members.

Step 1 - Delete the webs you are replacing

Hold Ctrl and click each web, or drag a selection box around them, then press Delete. Keep any web that meets a pitch break; you’ll make it vertical in the next step instead.

Step 2 - Right-click near the lower end of a web that meets the left pitch break, and choose Move Lower End to Make Vertical

This rotates the web so it is vertical, which saves adding a new member. The option only appears when you right-click near the end of the web in the scene. To add a new vertical instead, click Create, choose Member, and double-click the vertical reference line at the left end of T2.

Step 3 - Right-click the vertical, choose Geometry, and choose Left Of Line

Using this option moves the vertical to the left of the pitch break's reference line, under the sloped top chord T1.

Step 4 - Hold Shift and click the bottom edge of T1, then Shift-click the bottom edge of T2

The first click cuts the vertical to T1. The second removes its cut against T2, so the vertical stops at the sloped chord. You can also delete the T2 cut under Top Cuts in the member properties.

Step 5 - Repeat for the right pitch break, with Right Of Line, T3 and T2

Step 6 - Add diagonal webs between the verticals

Click Create and choose Member, then click from the bottom inside corner of a vertical to where the top chord needs support. For a symmetric panel, add a reference line centered between the verticals and run each diagonal to it. With the new web selected, Shift-click a line to cut the web to it.

Analyze the girder

Step 1 - Click Analysis Options

Analysis Options is the gear button next to Analyze in the top toolbar.

Step 2 - Check Detailed

A detailed analysis provides more information about any failed check. Detailed is unchecked by default; select it to enable detailed results.

Step 3 - Close the options and click Analyze

Step 4 - Click Analysis and History to see the results

To view the results, see Run & View Component Analysis.

Review carried components and hangers

A girder from a layout carries the jacks that frame into it. The truss drawn above carries nothing, so these steps apply only to a girder with carried components. To add carried components yourself, see Create Girder and Jack Roof Truss Connections.

Step 1 - Expand Connections in the right sidebar to review the carried components

The analysis applies each carried component's load at its connection. Closed jacks hang from the girder, so each has one connection on the bottom chord. Open jacks are toe-nailed to both chords, so each has a top chord and a bottom chord connection.

Step 2 - Click Menu next to Hangers and choose Select Hangers

Paragon selects a hanger for each bottom-chord connection and displays it in the scene. Hangers are available to layout users.

Step 3 - To change a hanger, select it under Hangers and choose a different Hardware, such as LUS26

The scene updates to show the new hanger.

Step 4 - Click Analyze to re-analyze the girder

Other hip trusses

The other hip trusses in the set usually need only some of edits. For each one, drop the flat top chord leaving Supports End Of Lay-In/Purlin unchecked where the purlins run across it. Then use Geometry, Left Of Line or Right Of Line to move the verticals at the pitch breaks under the sloped top chords, and fix their cuts. Analyze each truss when you're done.

Watch the video

In this video, the hip trusses from Training Plan 3 are opened from the layout (the D series in the garage and the E series on the rear porch) and optimized in design mode. The steps above draw a single hip girder instead, since the sample layout isn't part of a new project.

Video Transcript:

In this video we are going to review the hip truss designs for Training Plan 3.

(D01-G)

Let's start off by zooming in on the garage area, and begin with reviewing our Girder truss labeled D01-G. We can simply double click on the truss, which opens it up in design mode. For this particular truss, we want to change our bottom chord to a 2x6 since it's carrying the jack trusses, along with a few other changes. Let's control click to select both of the bottom chords. Then right click and select edit lumber, here we will change the dimensions to a 2x6.

Next, we're going to select the top chord, then Right click, and select drop flat top chord. Make sure the thickness is set to an inch and a half at the 8/12 slope. This truss will support the end of lay-in purlins. So, make sure to check the box. Click Drop to apply the changes.

Now let's add verticals at the shoulder joints and adjust the webbing in the middle. So, let's press the control button and drag across the 4 web members and press delete.

Next, we will add in our new members.

So, let's right click and select member. We're going to insert a member to the right side. To do so, double click to select the vertical reference line at the right end of T2. Then we need to change the alignment. Right click and click on Geometry. Then we need to select Right of Line, so it aligned to the right side.

While W1 is still selected let's go over to the properties panel and review the top cuts. Here we will delete the cut against T2.

Next let's add another member to the left end of T2. Right click and select member, then double click on the vertical reference line at the left end of T2. Then we need to change the alignment. Right click and click on Geometry. Then we need to select Left of Line, so it is aligned on the left side.

While the new vertical web is still selected review the top cuts in the Properties panel. This time we will delete the cut against T2. Notice that the cut is removed from the properties.

We will now add webs between the verticals.

Let's add a reference line which will be used for our diagonal webs. Right click and select reference line, we want this reference line to be centered between the vertical, so select the left most side of the W2 and then the right most side of W1. This will divide the panel in two.

Here we will add a member from the bottom right inside corner of W2 to where the reference line intersects the bottom edge of T2.

With the new web still selected, press shift and cut against the reference line.

Next, we will repeat this for the other side. Right click and select member. Then place the member from the bottom left inside corner of W1 to where the reference line and the bottom edge of T2 meet.

Let's re-analyze this truss. Select detailed analysis from the Gear icon and then select analyze.

Here we can see the loads being applied from the carried components. Let's review the carried components from the Collections Panel. Notice all of the connections are applied to the bottom chord. This is because the carried jack trusses are closed. Next, scroll down to access the Hangers menu, and click Select Hangers. This will auto-select hanger solutions and display them on the bottom chord. To change a hanger, select it from the collections panel and change the Hardware to the desired hanger. For this example, we'll change the LUS24 to LUS26. Click on the LUS24 and then select LUS26 from the list. Notice, the Scene is updated to reflect the change.

Next let's re-analyze the hip girder.

Looks like our hip girder is now good and we are ready to move on.

(D02)

Let's return to the layout and take care of these additional hip trusses. So, double click on D02. Select the top chord, Then, right click. And select Drop Flat Top Chord. Then we need to click Drop to accept this at the bottom.

Next, we will shift the vertical webs to cut against the sloping top chords. Select W2, right click, and click Geometry, and then we will select Left of Line. With the vertical still selected, hold Shift and select the bottom edge of T1 to add a cut, and then click the bottom edge of T2 to remove the cut.

Repeat this for W5. Select W5, right click, select Geometry, and then select Right of Line. With the vertical selected, hold Shift, and select the bottom edge of T3 to add a cut, and then click the bottom edge of T2 to remove the cut.

Click analyze to finalize this design. We are good here.

(D03)

Let's go back to our layout. We are going to Double click the D03 truss to open it up.

Here, we will select the top chord. Then, right click, and select drop flat top chord. Click Drop at the bottom to apply the change.

Next, we'll shift the vertical webs to cut against the sloping top chords. Select W3, right click, in the geometry option, and then select Left of Line. With the vertical still selected, hold Shift and select the bottom edge of T1 to add a cut, and then click the bottom edge of T2 to remove the cut.

Repeat this for W5. Select W5, right click, click on Geometry, and select Right of Line from the options. With the vertical still selected, hold Shift, and select the bottom edge of T3 to add a cut, and the bottom edge of T2 to remove the cut.

Analyze this truss. And everything looks good with D03.

(D04)

Return to the Layout and double click on our D04 truss to open this last one in our D series trusses.

Once again, we will drop the top chord. So, select the top chord, and then right click, and select drop flat top chord. Then select drop to accept.

Similar to the previous flat top common trusses, let's add vertical members at the pitch breaks. Rather than adding vertical webs, we'll modify the existing diagonal webs by making them vertical.

We'll start by deleting W3. Then right click toward the bottom of W2, and then select Move Lower End to Make Vertical. That rotates an existing member to be vertical. Next, right click toward the bottom of W3, and select Move Lower End to Make Vertical. This saves a few steps in editing and adding in a new member.

Now we need to add a couple diagonal webs.

Right click, select member, we will add a member back in for the left side of W2. Let's create a web between the bottom of W1 and the top of W2. We will clean up the connections here. We will cut this back by holding shift, and then cut against the reference line, and then B1.

Let's create another member between W3 and W4. Right click, select member, and create a web between the top of W3 and the bottom of W4. Let's clean this up. While holding shift, we will cut this against B2 and the reference line.

That looks better. Let's analyze this one and see what we have.

Alright, that does it for those D hip set members.

(3D)

Let's take a look in 3D for our D series trusses. Here we can see our modified webbing and dropped flat top chords we added.

(E Series)

Next, we are going to use many of the same tools to optimize the E series trusses. Pan over to the rear porch area, and zoom in on the porch to focus our efforts here.

Let's begin editing.

(E01-G)

Double click the E01-G truss.

Select the bottom chord, then right click, and select edit lumber. Here we will change this to a 2x6.

Next, Select the top chord, then right click and, select Drop flat top chord. Notice the Crossing Slope is set to 6/12.

Click to add the option for supports ends of lay-in purlins which effects the vertical drop distance. Then click drop to accept these changes.

We're also going to adjust the diagonal webs to be vertical members at each pitch break.

Let's start on the left side. Right click near the bottom of W1, and select, Move Lower End to Make this one Vertical. With the member selected, change the Location to Left Of Line by right clicking and then select Geometry, then click on Left of Line. Press shift and click the edge of T1 and then on T2 to clean up the cuts.

We will repeat this on the right. Right click near the bottom of W2, and select, Move Lower End to Make Vertical. With the member selected, right click and select Geometry, the from the options change the Location to be Right Of Line. Press shift, and click the edge of T3 and then on T2 to finalize the joint.

We need a diagonal web between the verticals. To add this, let's Right click, select member, and then add the member between W1 and W2.

Let's review the Carried Components over in the properties panel. Slide down to the Carried Components and you will notice there are 10 entries, which include both Top and Bottom Chord connections. This is because, the carried components are open jacks, which will be toe nailed at the top and bottom chords.

Next, we will add the hangers. To do this, click the Hangers menu at the right, and Select Hangers. TJC 37s were auto-selected to carry the corner girders.

Finally, let's analyze the truss. Everything looks good here.

(E02)

Move back over to the layout, and we will double click the E02 truss and make a few adjustments. Here, we are going to select the top chord, then we will right click and select drop flat top chord to drop it. And then select drop at the bottom to accept the changes.

We need to make a few other modifications to this truss. Starting with W1, right click, and select geometry, here we will choose Left of Line. Next press Shift, and add a cut against T1, and then we will click T2 to remove the cut.

Repeat this for W3. Right click, select geometry, and choose Right of Line. Then we will press the shift key, and add a cut against T3, and then we will click T2 to remove this cut.

There we go. Let's re-analyze this one.

And all looks good.

We hope this video provided you with some practical examples of how to drop top chords, add, and modify webs, and adjust member cuts.

Thanks for watching.