When the World Trade Centre was built, a lot of people wondered how to make building materials more efficient

Buildings are made from concrete, steel and wood.

But that material is not always easy to find and recycle.

The New York Times recently published a fascinating article that explores what’s involved in finding the best building materials.

And the paper highlights a few key points about finding the right materials.

We spoke to a few experts to find out how to recycle the most important building materials in the world.

What’s more, the authors also outline how you can start using them in your own projects, without the need to buy anything from a recycler.

This article is part of the series on how to build sustainable buildings.

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