Get matched with top excavation pros in Estelline, SD

If you don’t have a crawl space but have a partial basement you want to make deeper, you can expect to spend a little less—between $40,000 and $90,000 on average. However, if you’re not adding new finished square footage, you won’t see much in the way of ROI.

The cost to dig a trench ranges from $400 to $1,200 per 100 linear feet, depending on the soil, depth, and width. Plan to spend $5 to $12 per linear foot for trenching (it’ll be on the higher end if you have rocky soil). Renting a trencher costs $100 to $250 per hour, depending on the type of trencher. 

Most residential basements are 8 to 10 feet deep. You can dig deeper depending on building codes, but it does become more difficult. You’ll likely need to install stronger foundation walls and additional supports to handle the increased load. Depending on the water table, you may also need a water management system. Clay soil can support a deeper foundation than sandy soil. A structural engineer will be able to tell you the maximum, feasible depth.

A mini excavator can dig between 5 and 11 feet deep, depending on the type and size of the mini excavator. Mini hydraulic excavators are more powerful and can reach deeper into the earth, but electric models have a more limited range. Mini excavators over two tons in size are also more powerful and able to dig as deep as 11 feet.