Modeling a dormer roof

00:04

The doma is a structure that projects vertically

00:07

from a sloping roof with its own roof construction

00:10

and usually contains a window.

00:13

They are commonly used to increase the usable space within an attic room.

00:17

As the addition of a dorma

00:19

extends the headroom beyond the existing roof

00:23

with a window allowing daylight into the attic

00:28

and zooming into the lower building.

00:30

Here, we can see the area of the roof where a door will be created

00:35

as the door is constructed of walls and a roof that project up from the existing roof,

00:40

it will be easier to create these in a plan view.

00:43

So from the project browser,

00:45

I'll open up the roof floor plan view

00:49

and looking at this view,

00:50

it will be useful if we can see beyond the roof to the objects below

00:54

in order to draw the walls accurately.

00:57

So to be able to do this, we'll go to the view control bar

00:60

and we'll change the shading mode from hidden line to be wire frame.

01:05

Now zooming into the lower building where we need to create the dorma,

01:09

we can see the objects beneath the roof and we'll align

01:12

the dorma walls to the mullions in the curtain wall here

01:17

to create the walls.

01:18

We'll go to the architecture ruin tab and from the BUILD panel,

01:22

we'll choose the wall tool.

01:24

Now, looking at type selector,

01:26

we can see that we have the generic wall six inch type selected

01:30

and looking at the options bar above,

01:32

we can see that we have an unconnected height of 8 ft.

01:36

The location line is set to be wall, center line

01:39

And now looking at the draw tools on the ribbon,

01:42

we had the line draw tool active.

01:45

So we'll go into the model

01:46

and now we'll snap to the middle of the internal edge of this mall here

01:52

and then we draw away and we'll type in the distance

01:54

of 7 ft six to create the length of this wall,

01:59

a press scope to finish drawing this wall.

02:02

And now we moved down to two mullions below

02:05

and we'll step to the middle at the back of this mullion again.

02:08

And we'll draw along

02:10

and line up with the wall that we've just created at 7 ft six long.

02:14

And we don't need a wall at the back of the door. So I'll press escape once more

02:18

and now we'll draw a wall across the front.

02:20

So snap into the existing two walls that we've just created,

02:23

wouldn't close those with this wall here.

02:27

So now we've created the walls. We'll click, modify to finish the wall tool

02:32

and looking at the curtain wall and the wall at the front.

02:34

Here, we want the inside face of the wall to align with the curtain wall.

02:39

So I'll go to the modify ribbon tab

02:41

and from the modify panel, we'll choose the align tool

02:45

and now select the back face of the mullion on the curtain wall here as the reference

02:51

and now the back face of this wall

02:53

to align to that reference.

02:58

So that finishes creating the walls. Now we need to create the roof.

03:02

So we'll go back to the architecture ribbon tab

03:04

and from the build panel, we'll choose the roof by footprint tool,

03:11

looking at the sketch roof boundary ribbon tools here,

03:13

we can see the draw tool is set to pick walls

03:18

and we'll go down to the options bar and across here,

03:20

we'll change the overhang to be six inches

03:24

and now we'll come and pick on the walls that we've just created,

03:27

making sure that the sketch line goes to the outside of the wall here.

03:31

So looking at the blue dash line and then click

03:34

to create those sketch lines around each of the walls.

03:39

So obviously, we don't have a wall across the back here to pick.

03:41

So we'll change the draw tool to be draw a line.

03:45

And now we're just snap between the two sketch lines that we've already created

03:49

and that will create the enclosed boundary that we need.

03:52

I choose, modify to finish creating the sketch lines.

03:56

We could see that none of these lines currently define a slope.

03:59

So using the crossing selection tool here,

04:01

I'll hold the mouse button down and drag across the top and bottom sketch lines.

04:06

And now go into the property's pallette.

04:08

We'll check the option here to define roof slope

04:12

and a little bit further down.

04:13

We can see that the slope parameter is currently set to 30 degrees. So

04:17

we'll change this to be five degrees.

04:20

And now that's applied, we can see the roof slope icon on both of these lines. So

04:25

that's the sketch finished.

04:26

We'll go back up to the ribbon and click finish, edit mode.

04:29

And now we're being asked about attaching the walls to the underside of the roof.

04:33

So the walls that we've created for the dorma and

04:36

we've used to base the sketch of the roof on

04:39

can be attached to the underside of this roof.

04:41

So we'll click attach for that to happen

04:45

and then we'll swap back to the 3D view

04:48

and we can see now that we've got the Doma roof here,

04:51

but it's too low and the walls are barely sticking out from the roof.

04:54

So

04:55

let's select the roof here

04:57

and going over to the properties pallet.

04:59

We can see we have the base offset from level parameter

05:02

which will change to be 2 ft three inches.

05:05

Once this is applied,

05:06

we can see the roof move up and also the

05:09

walls that we attach to the roof are followed with it

05:12

and looking at the bottom of the walls,

05:13

they're actually sticking out from the roof now and we

05:15

need these to follow down the main roof slope.

05:19

So we'll select these walls.

05:21

So hovering over one here and then pressing the tab

05:23

key to cycle through to the chain of walls and

05:26

then we'll click to select those.

05:29

Now, going up to the modify walls, ribbon tab,

05:32

we see we have the attached top base tool,

05:35

so we'll click on this.

05:37

And now in the options bar, we'll set the base of the walls to be attached.

05:41

Now, we just need to click the main roof

05:44

and those walls will be attached and we can now see them following down

05:48

the slope of the roof here as required for our dorma

05:51

looking at the Doma roof here,

05:53

we can see that this doesn't quite meet the main roof either.

05:56

So we need to extend this back.

05:59

So from the modify ribbon tab on the geometry panel here,

06:02

we'll choose the roof joins tool.

06:05

And now we just need to pick one of the back edges of the roof

06:08

and then the face of the main roof.

06:10

And now we can see that that's joined in and it's

06:12

given us the junction that we need for the door here.