Sun Map and House Position Tool
Find your block, place a floor plan on it, add the neighbours and scrub through the day. The map shows the sun path and the shadows for any date, and the summary tells you which rooms get sun in winter and which get shaded by the house next door.
How it works
Find the block
Search the address or tap the map. The lot boundary is looked up from the state cadastre where one is available, or you draw it.
Place the house
Pick a sample footprint or enter a width and depth. Drag it into position, rotate it in single degrees and mirror it to suit the block.
Add the neighbours
Drop single or double storey boxes on the adjoining lots. Their shadows are what usually decide whether a backyard gets winter sun.
Check the sun
Pick a solstice, an equinox or today and slide through sunrise to sunset. Open the summary for a room-by-room reading.
What it does not model
The block is treated as flat. Trees, fences, roof pitch, eaves overhangs and hills are not included, and the room-by-room summary tests a point just outside each room's nearest external wall rather than every window. It is a planning aid for comparing orientations and plans, not a substitute for a site survey or a shadow diagram prepared for a development application.
Frequently asked questions
- How accurate are the shadows?
- The sun's position is calculated to within a fraction of a degree for the block's own time zone. Shadows are cast by simple flat-roofed boxes at 3.6 m (single storey) or 6.6 m (double storey) to the eaves, which you can change. The block is treated as flat, and trees, fences and roof pitch are not modelled, so treat the result as a guide rather than a survey.
- Where does the lot boundary come from?
- Where a state publishes its cadastre freely (NSW, Queensland, Victoria, Western Australia, Tasmania and the ACT), the tool looks up the parcel under your address automatically. Elsewhere, or if the boundary looks wrong, you can draw it by tapping the corners of the block.
- Which dates should I check?
- 21 June is the winter solstice, when the sun is lowest and shadows are longest. 21 December is the summer solstice, when the midday sun is nearly overhead. The equinoxes in March and September sit in between. Checking winter is the most useful test of whether living areas will get sun.
- Can I use my own floor plan?
- Version one ships with five sample footprints and a custom rectangle you can size by width and depth. Footprints from Homebuilds home designs are planned for a later release.
- Does it save my work?
- Everything you set up is encoded in the page link. Use Share link to copy it, and reopening that link restores the same block, house, neighbours, date and time. Nothing is stored on our servers and no account is needed.