4 Jun 2006

On green roofs

I struggle to see much 'green' about green roofs. What you are doing is going to great expense to make a roof look like a meadow. Which it's not - it's a roof. You have to beef up the rafters because of the extra weight. You have to tank the roof with a hi-tech (and not very green) waterproof layer laid over sheathing ply - so you basically have something like a felt roof at this point - and then you have to go to great lengths adding edging materials to ensure that your organic matter doesn't slide off and become a large mound of slurry. Oh, and it all costs a fortune.

What is the point?

1 comment:

  1. Good points! I’ve always thought that green-minded people should take a long trip to some developing country in order to see some real green building. Using organic materials, moss roofs are very handy. Rudimentary tools make it difficult to prepare refined roofing materials, so moss/grass layer on top of bark roof creates resilient and heavy (withstands sunlight and doesn’t get blown away) cover that is carefree. Finally it is easy to replace the whole roof if it needs mending. Modern materials under such arrangement are already so strong that they don’t need that extra cover.