Like the layers of caramel shortbread slipping over one another in the hot sun, in a translational landslide the mass moves along a roughly planar, flat, surface with little rotation or backward tilting.
According to a customer the average cost of a home extension is Â£25,000. A Double Storey Extension costs between Â£45,415 and Â£76,000. A Single Storey Extension costs between Â£22,916 and Â£37,000. Planning and Preparation for a home extensions costs between Â£5,132 to Â£10,150.he approximate price of a timber extension to work on is around Â£1200 per square meter based on Evis Build for a 60 square meter rear extension. For a double storey extension, you should consider about 160% of the price for a single storey extension of the same floor area.
So, for your 4 x 5m extension, the build cost would be roughly Â£24,000. + Add on 10-15% for professional fees (architect, planning application, building regs, structural engineer).+ VAT. Single storey extension = Â£32,000.s a rule of thumb you can add 50% extra to the build cost of a single storey extension. So, Â£24,000 +50% = Â£36,000. + Add on 10-15% for professional fees (architect, planning application, building regs, structural engineer). + VAT.