Mantle (geology) The mantle is a layer inside a terrestrial planet and some other rocky planetary bodies. For a mantle to form, the planetary body must be large enough to have undergone the process of planetary differentiation by density.
Found the The HandR Average Build Cost Guide on the homebuilding.co.uk website, which is exactly what I need for estimating the cost of newbuilds. From this got a cost of ~Â£1400 per m^2. I still don't have any accurate information on demolition though apart from on average 3/5-10k per house.ound the The HandR Average Build Cost Guide on the homebuilding.co.uk website, which is exactly what I need for estimating the cost of newbuilds. From this got a cost of ~Â£1400 per m^2. I still don't have any accurate information on demolition though apart from on average 3/5-10k per house.
If you plan to buy most of the raw materials and undertake much of the work yourself, Channel 4 estimates that a single storey (20 metre square) extension will cost Â£15,900 (or Â£795 per square metre) whilst a two storey (40 metre square) extension will cost Â£28,040 or (Â£701 per square metre).