Digging down the basement would add an about $20k-$25k to the total cost of the construction. I would estimate that, for a townhouse, the total cost of a basement is around $70,000. For a bigger house, closer to $100,000.
Digging out a basement (also known an Underpinning or Basement Lowering) can be an ideal way to add some room or living space to your home and can often be less expensive than adding room by going upward or outward. The best option can be chosen after considering a few factors such as design, feasibility, function, and the cost.
To renovate a 12'x35′ rowhome basement from 6 feet to 8 feet would cost in the neighborhood of $15k-$20k. For that price, the scope of work typically includes breaking the slab, underpinning, excavating, installing the waterproofing system and new concrete pour.
This undermines neighboring structures and utilities and creates potentially dangerous conditions for your basement dig-out. When granular soil is present, soil grouting can be performed in advance of the basement excavation to stabilize the soil and help ensure the safety and success of your dig-out project.
Cost - the actual dirt removal could run probAbly about $2000-5000 depending on accessibility - it dirt removal by wheelbarrow to a bobcast parked at a basement door, by conveyor through a window, or hand carried by bucket up stairs to the yard. And how hard digging is it, and is dewatering required, etc.
How much a basement should cost. Average costs and comments from CostHelper's team of professional journalists and community of users. Including a basement as part of new house construction can increase the cost of the house by $10-$25 or more a square foot for an unfinished basement, or about $10,000-$50,000 or more for an average house; and $30-$100 or more a square foot for a finished