Skylights and Dormers

Click on a roof and the unit is set in it, the roof cut to its shape. Roof windows that open, fixed skylights, sun tunnels, five styles of dormer and chimney stacks, each with every part adjustable.

Add a skylight

14 to start from

Roof windows, skylights and chimneys, then dormers. Each one is a starting point; every part can be changed once it is on the roof.

  • Chimney Stack in 3D

    Chimney Stack

    2 pots, flaunching cap. 900 by 450 mm, 1800 mm tall.

  • Tall Chimney in 3D

    Tall Chimney

    3 pots, corbelled cap. 1350 by 450 mm, 3000 mm tall.

  • Roof Window in 3D

    Roof Window

    Roof window, centre pivot. 780 by 1400 mm.

  • Top-Hung Roof Window in 3D

    Top-Hung Roof Window

    Roof window, top hung. 940 by 1600 mm.

  • Flat Skylight in 3D

    Flat Skylight

    Flat skylight. 1000 by 1000 mm.

  • Domed Rooflight in 3D

    Domed Rooflight

    Domed skylight. 900 by 900 mm.

  • Pyramid Rooflight in 3D

    Pyramid Rooflight

    Pyramid skylight. 1200 by 1200 mm.

  • Sun Tunnel in 3D

    Sun Tunnel

    Sun tunnel. 450 by 450 mm.

  • Recessed Dormer in 3D

    Recessed Dormer

    Recessed dormer with a casement window. 1800 mm wide.

  • Wall Dormer in 3D

    Wall Dormer

    Wall dormer with a casement window. 1400 mm wide.

  • Gable Dormer in 3D

    Gable Dormer

    Gable dormer with a casement window. 1600 mm wide.

  • Shed Dormer in 3D

    Shed Dormer

    Shed dormer with a casement window. 3000 mm wide.

  • Hipped Dormer in 3D

    Hipped Dormer

    Hipped dormer with a casement window. 1800 mm wide.

  • Georgian Dormer in 3D

    Georgian Dormer

    Gable dormer with a double hung window. 1200 mm wide.

Every property, and what it does

Each kind has its own Design panel: the roof window and skylight first, then the dormer, then the chimney. A field shows when it applies.

Roof window: Type

What kind of unit it is and how its leaves are made.

FieldWhat it doesValues
TypeA roof window opens; a skylight is fixed. A sun tunnel is a small round shaft.Roof window, Flat skylight, Domed skylight, Pyramid skylight, Sun tunnel; default Roof window
OperationHow the roof window opens: fixed, pivoting about its middle, or hung from its top.Fixed, Centre pivot, Top hung; default Centre pivot
ShapeThe roof is cut to match, so a round skylight gets a round hole.Rectangle, Circle, Ellipse; default Rectangle
Corner radiusRounds the corners of a rectangular head.0 to 300 mm; default 0 mm

Roof window: Operation

How it opens, and how far it is shown open.

FieldWhat it doesValues
OpenSwings, slides or tilts the moving parts open. Saved with the design, so a door can be left ajar in a render.0 to 100%; default 0%

Roof window: Curb

What the unit stands on, and how it is weathered into the roof.

FieldWhat it doesValues
Curb heightHow far the unit stands proud of the roof surface. 0 sits it flush.0 to 500 mm; default 150 mm
Curb thicknessThickness of the curb walls the unit sits on.20 to 200 mm; default 60 mm; advanced
FlashingThe apron that weathers the joint between the unit and the roof.None, Standard, Recessed; default Standard
Curb finishThe finish of the curb.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted grey
Flashing finishThe finish of the flashing.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Aluminium grey; advanced

Roof window: Frame

The frame around the opening and its finish.

FieldWhat it doesValues
Frame widthFace width of the frame around the opening.25 to 180 mm; default 70 mm
Frame depthHow deep the frame is.30 to 200 mm; default 80 mm
Frame finishThe finish of the frame.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted white

Roof window: Glazing

The glass: layers, tint, coating and thickness.

FieldWhat it doesValues
GlazingClear, tinted or obscure glass.Clear glass, Tinted glass, Obscure glass; default Clear glass
Panes per unitSingle, double or triple glazing. Shows as the edge thickness at the reveal.1 to 3; default 2
TintA body tint in the glass itself, as opposed to the obscure-glass finish.Clear, Bronze, Grey, Green, Blue; default Clear
OpacityHow much the glass hides what is behind it. 1 is ordinary clear glazing.0.2 to 1; default 1; advanced
Low-E coatingA low-emissivity coating: a faint green-blue cast and slightly less light through.On or off; default off; advanced
Unit thicknessThe overall thickness of the glazed unit.4 to 60 mm; default 26 mm; advanced
Bars acrossHow many panes the glazing bars make across.1 to 6; default 2; advanced
Bars upHow many panes the glazing bars make up.1 to 6; default 2; advanced
Bar widthWidth of each glazing bar.8 to 60 mm; default 20 mm; advanced
Dome riseHow high a domed skylight rises.40 to 800 mm; default 220 mm
Glazing barsDecorative glazing bars within the glass.None, Colonial, Prairie, Diamond, Craftsman; default None; advanced

Roof window: Shaft

The tube of a sun tunnel.

FieldWhat it doesValues
Shaft lengthHow far the tube reaches down toward the ceiling below.200 to 3000 mm; default 900 mm
Shaft finishThe finish inside the sun tunnel shaft.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Aluminium white

Roof window: Hardware

Handles and fittings.

FieldWhat it doesValues
HandleShows the opening handle.On or off; default on
Handle finishThe finish of the handle.Chrome, Brass, Painted black, Steel, Bronze; default Aluminium grey

Dormer: Dormer

The dormer itself: its style, size and roof.

FieldWhat it doesValues
StyleGable is the classic doghouse; shed is a single slope; hipped is a gable with its front hipped back; recessed cuts into the slope instead of standing out of it.Gable, Shed, Hipped, Recessed, Wall; default Gable
Edge trimFascia adds a board along the eave; full adds barge boards up the rakes as well.None, Fascia, Full; default None; advanced
Valley flashingThe lead where the dormer meets the host roof. Without it the joint is a bare seam.On or off; default on
Flashing finishThe finish of the flashing.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Aluminium grey; advanced
Drop below eaveHow far the front face continues down the wall below the eave. A wall dormer rises out of the wall rather than sitting on the roof.100 to 2500 mm; default 700 mm
Recess depthHow far the recess cuts back into the roof. Its height follows from the pitch.800 to 3000 mm; default 1600 mm
WidthWidth of the dormer across the roof.600 to 6000 mm; default 1600 mm
Front wall heightHeight of the front wall above the roof surface. The dormer's depth follows from this.600 to 3000 mm; default 1500 mm
Dormer roof pitchMust stay below the host roof's pitch on a shed dormer, or it never meets the roof.5 to 60°; default 30°
Hip runHow far the front of a hipped dormer slopes back.100 to 2000 mm; default 500 mm
EavesHow far the dormer roof reaches past its walls.0 to 600 mm; default 150 mm; advanced

Dormer: Window

The window in the dormer front.

FieldWhat it doesValues
Window casingTrim around the dormer window, on its front face.None, Flat, Moulded, Craftsman; default None
Casing widthFace width of the casing boards.20 to 200 mm; default 70 mm; advanced
Window marginWall left around the window in the dormer's front face.50 to 800 mm; default 200 mm
OperationHow the window opens.Fixed, Casement, Awning, Hopper, Tilt and turn, Single hung, Double hung, Slider, Pivot; default Casement
Lights acrossHow many lights the dormer window has across.1 to 4; default 1
Glazing barsDecorative glazing bars within the glass.None, Colonial, Prairie, Diamond, Craftsman; default None; advanced
Frame widthFace width of the frame around the opening.25 to 150 mm; default 60 mm; advanced
Sash widthFace width of the opening sash.15 to 120 mm; default 45 mm; advanced
Frame finishThe finish of the frame.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted white
Sash finishThe finish of the sash.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted white
Handle finishThe finish of the handle.Chrome, Brass, Painted black, Steel, Bronze; default Chrome
Lights upHorizontal divisions of the dormer window.1 to 3; default 1

Dormer: Construction

Wall and roof thicknesses and finishes.

FieldWhat it doesValues
Cheek thicknessThickness of the dormer side walls.50 to 400 mm; default 150 mm; advanced
Front wall thicknessThickness of the dormer front wall.80 to 500 mm; default 200 mm; advanced
Roof thicknessThickness of the dormer roof.40 to 400 mm; default 120 mm; advanced
CladdingThe finish of the dormer cheeks and front wall.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted white
Roof finishThe finish of the dormer roof.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted grey

Dormer: Operation

How it opens, and how far it is shown open.

FieldWhat it doesValues
OpenSwings, slides or tilts the moving parts open. Saved with the design, so a door can be left ajar in a render.0 to 100%; default 0%

Dormer: Glazing

The glass: layers, tint, coating and thickness.

FieldWhat it doesValues
GlazingClear, tinted or obscure glass.Clear glass, Tinted glass, Obscure glass; default Clear glass
Panes per unitSingle, double or triple glazing. Shows as the edge thickness at the reveal.1 to 3; default 2
TintA body tint in the glass itself, as opposed to the obscure-glass finish.Clear, Bronze, Grey, Green, Blue; default Clear
OpacityHow much the glass hides what is behind it. 1 is ordinary clear glazing.0.2 to 1; default 1; advanced
Low-E coatingA low-emissivity coating: a faint green-blue cast and slightly less light through.On or off; default off; advanced
Unit thicknessThe overall thickness of the glazed unit.4 to 60 mm; default 24 mm; advanced

Chimney: Size

How big the stack is.

FieldWhat it doesValues
WidthAcross the slope. A single-flue stack is about 450 mm, a double 900300 to 3000 mm; default 900 mm
DepthUp the slope. Measured in plan, not along the roof300 to 3000 mm; default 450 mm
HeightFrom where it leaves the roof to the top of the brickwork300 to 8000 mm; default 1800 mm

Chimney: Top

How the stack is finished at the top.

FieldWhat it doesValues
CapFlaunched is the mortar fillet everybody has; corbelled oversails firstFlaunching, Corbelled, Plain; default Flaunching
PotsOne per flue. Zero is a capped stack0 to 6; default 1
Pot heightHeight of each chimney pot.100 to 1200 mm; default 300 mm
Pot sizeDiameter of each chimney pot.100 to 600 mm; default 220 mm

Chimney: Finish

What each part of the chimney is made of.

FieldWhat it doesValues
BrickworkThe finish of the chimney stack.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted grey
FlaunchingThe finish of the mortar fillet at the top of the stack.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Painted white
PotsThe finish of the chimney pots.Painted white, Painted black, Painted grey, Oak, Walnut, Pine, Aluminium black, Aluminium white, Aluminium grey, Steel, Bronze; default Bronze

How to add one to a roof

  1. Open the Window tool

    In the editor, open Structure and choose Window, or type WINDOW (WI). Roof windows, skylights, dormers and chimneys are in its style picker.

  2. Click on a roof

    Pick a style, then click where it goes on the plan. The roof plane under that point takes it, and its outline shows on the roof before you click.

  3. The roof is cut

    A skylight cuts its own hole, round for a round one; a dormer builds its cheeks, front wall and roof, with lead where it meets the main roof.

  4. Design it

    Its Design panel changes the type, curb, glass, finishes and, for a dormer, its style, size and window.

Roof questions, answered.

What can I put in a roof?

Roof windows that pivot or hang from the top, fixed flat, domed and pyramid skylights, sun tunnels, gable, shed, hipped, recessed and wall dormers, and chimney stacks.

Do I need a roof first?

Yes. These are placed on a roof: the plan point you click decides which roof plane takes it.

Can a skylight be round?

Yes. A skylight can be a rectangle, circle or ellipse, and the roof is cut to the same shape.

How tall is a chimney?

From 300 mm to 8 m above where it leaves the roof, with up to six pots and a flaunched, corbelled or plain cap.

Read on

  • Window Design: Windows in walls, flat or as a bay.
  • Roofs docs: Hipped, gabled, shed and flat roofs with pitch and eaves.
  • Door Design: Internal, front, sliding and garage doors.