Welcome to the Bunnings Workshop community. Thank you for joining us and sharing your question about how much paint do I need to cover my timber fence.
If your fence is 45 meters long and is 2.1 meters tall we simply need to multiply these two units to get your area. Multiplying these two numbers gives us an answer of 94.5 square meters. Because we are painting both the front and back of the fence we will need to multiply this answer by two. This will give us a total area of 189 square meters.
The estimated coverage of 1 litre of paint is conservatively 16 square meters. This depends on the thickness of the applied coat and the spread of the paint. We now divide the 189 square meters by the 16 square meter coverage. This gives us an answer of 11.81 litres. But since we are putting two coats we multiply this amount by two. This will give us an answer of 23.63 litres rounded up.
I recommend getting 1 can of 15 litres and 1 can of 10 litres. I suggest using Dulux Weathershield for your fence. It is self-priming and has UV protection mixed into it. All that's left is to choose a colour that you like from the Dulux colour range. This sounds like a fantastic project. Any updates you can provide while painting your fence would be much appreciated. Please note that if your fence has just been recently installed, it will need a minimum of six weeks to season before you can paint it.