Step 1: Make a Base With Plastic Bins
For the base of the bench, I used 4 plastic storage bins - They come in many different heights and sizes so you need find some that will work for your balcony. This is a great way to keep construction down to a minimum and also gives you some long term storage if you need it. Just make sure that you pick bins that have a solid top like this to keep the water out. I arranged them to give me an L-shaped bench.