Q. I am installing flagstone and some paving brick on top of a concrete patio. A book I read suggests mixing sand, cement and hydrated lime in different proportions to make the mortar mix. What is ...

Our built world is full of dirty secrets. So many of the things we imagine to have little impact on our environment turn out to be remarkably unsustainable. Concrete, bricks, asphalt—we encounter ...

Environmentally friendly 'living concrete' has been developed by scientists mixing sand, gel and bacteria to create a building material as strong as cement. The new material contains a form of ...