This is the question that a Spiked reader asks Ethan Greenhart in Ask Ethan. Ethan begins with his own question:

Dear Dalton, I must beseech you to stop work immediately! Why on Mother Earth would you want to extend your house? Hasn’t your size-12 carbon footprint crushed enough of our precious planet?

Read the full answer for yourself, but here is our favourite part (of course!):

As for the toilet, we can go further than Ken suggests. Let’s recycle that adage to: ‘If it’s brown, bury it in the ground; if it’s yellow, recycle it like a good fellow.…’ For example, a simple hut made from reclaimed timbers can house a very adequate composting toilet. To be honest, I find the whole process of rotting one’s wastes to produce food to be extremely fascinating. I’m an avid reader of Composting Toilet World. When we hear the ‘call of nature’, she is saying ‘return your wastes to me!’ The Greenhart motto is: ‘Open your bowel, close the loop.’ (Sorry, I guess you’d call that composting toilet humour!) Think how well your rhubarb will grow. The neighbours will be green with envy.

Obviously, there is a little more to a decision like this. And, this applies to everything we do. Being green is good, of course. But, I guess the golden green rule would be to always step back for a minute and decide if you really need the new item you are thinking about building or buying.