Dry Stone Walling
Over the last, erm, 15 months, I've been building this dry stone retaining wall in the garden. I didn't think of it as an eco-option at first as stone is non-renewable, but then I compared it to its brick equivalent and realised:
1. stone has a lower embodied energy than brick
2. no mortar = less energy intensive cement manufacture
3. the gaps provide refuge for wildlife
The bonus is the source of the stone - Ladycross Quarry near Hexham. The stone is quarried by hand and the already quarried areas are converted into a nature reserve as they go along. It is a truly beautiful development - I have never heard or seen so many birds in one place in this country.