Does anyone have any idea how much it would cost to replace an existing grunnmur with a new one, including of course insullation and drenering.

We have an existing house in Eidsvoll from 1891 with a grunnflate av ca. 9 m x 7 m. The existing grunnmur is made primarily from large stones, but patched at some later point in time with bricks and mortar. The ground is solid clay (for at least 10-15 meters down) and there is easy access to and around the entire house.

The house is constructed of logs and påkledd. The grunnmur supports all of the outerwalls and one inner wall down the middle, which divides the rectangular shape of the building in half. Attached is a diagram of the structure of the house as it presently sits on the grunnmur, as well as two photos of the house itself.

We are in the process of planning an addition to the house in which we will be constructing a new grunnmur next to the existing one (adding at most in additional 8 m x 7 m). Since the existing grunnmur has had some settling that we will need to repair, it needs drenering, and it needs insullation and since we're in a crunch for space within the dimensions of our piece of property (+ need for teknisk rom and storage space--no garage), we want to make the kjeller under this old portion of the building into useable space by install a new grunnmur. But is it really worth it for the cost per kvm?

Anyone know of an approximate cost for such a job? This is work that we're not going to do ourselves.

Any recommendations for a firm in the Eidsvoll area?