How to find out when your house was built

For a house in NSW, the quickest way is to look at old aerial photos. Find the last photo with an empty block and the first one with a roof, and your house was built between the two.

Narrow it down with aerial photos

Search your address on the home page.
Pick the oldest year on the strip under the photo. In Sydney that's usually 1943; in other places the photos start later.
Step forward a year at a time until a roof appears on your block.
Note the two years either side. A paddock in 1955 and a house in 1965 means it was built in those ten years.

Compare years puts the two photos side by side with a divider you can drag, which makes the change easy to see.

What the photos can't tell you

The exact year. Photos were taken years apart, and in some places decades apart, so you get a range.
Anything before the first photo. If the house is already there in the oldest one, all you know is that it's older than that.
Whether it's the same house. A roof in 1943 may belong to an earlier house that was later knocked down and replaced. Look for the roof changing shape.

Where to find an exact date

Your council. Councils keep building and development applications, and can often tell you when a house was approved or finished.
Your local library. Local studies collections hold old rate books, street directories and subdivision plans, and the librarians know how to use them.
Land title records. A historical title search from NSW Land Registry Services shows when the land was subdivided and each time it was sold. A sale soon after a subdivision often means a new house.
Your sale contract. The papers from when you bought may include a sewer diagram or building certificate with a date on it.
Your local historical society. Someone there may already have researched your street.

Start with the photos

It takes a minute and it's free. Search a NSW address or suburb, or browse suburbs A to Z.