And Other Factors in
Preparing Your Land Parcel for Building

There are several things to consider when preparing your building lot for your small house. Some of the considerations will include determining the frost depth for your land parcel, staking out the location and position of your foundation, and hiring an excavator that is familiar with your soil type and setting up erosion control.

Your excavator will be beneficial in helping you determine all of these factors so you want to be certain that you hire one with comprehensive knowledge of your geographical area and topography. Your excavator will work with the building inspector to ensure the project is completed to proper code specifications. Here’s a case where you might start with a neighbor, maybe in a new-ish house, to ask about a good excavator in your area.

When you are choosing an excavator, it is a good idea to inquire about other projects the excavator has completed on parcels with your soil type. This could include recent projects as well as past projects, so you can determine the long term results of the excavator’s workmanship. As with everything else, doing your homework before choosing an excavator, will save you headaches and additional expenses in the future.

Water is Not Your Friend

It is especially important that your excavator determines the correct frost depth because in doing so, it will prevent your foundation from frost heaving. Water has the interesting habit of expanding when it’s frozen. So whether it gets under the foundation or penetrates into the concrete it’s like a miniature crow bar wedging the concrete apart and out of the way.

Heaving occurs when the ground thaws and freezes thus causing your foundation to shift and crack. So you either have to locate the bottom of your foundation under the frost line (four feet in Wisconsin!), or pour a floating slab on top of well-drained gravel. Although some cracking is normal in the years following the project, you want to be able to troubleshoot this problem from the beginning and as much as possible.

If your soil contains a lot of water, choose an excavator that has sufficient experience with drainage and erosion techniques. Your excavator can determine the proper frost depth and excavate according to depth specification. However, if your excavator is inexperienced with high water density soil you will still have future problems with your foundation. For this soil type, it is necessary to install drainage tile at the base of the foundation and excavate the land in a manner that allows the water to drain away from the foundation.

If your excavator is not aware of the amount of water in your soil during this phase of your project, it could end up costing you thousands of dollars later. The result could mean digging the soil away from the foundation, installing proper drainage and possibly re-excavating your land to correct drainage problems.

I personally had a BIG problem with this in the first winter following construction. The final grading wasn’t fully completed before winter came around, leaving a very slight pitch toward the exposed basement windows on the south side of the house. When I was hit with a 40+ degree day in February the quickly melting snow couldn’t percolate into the frozen ground and consequently accumulated around that low spot in front of the windows.

Although the depth of frost penetration depends on the soil type for your area, it is still an important factor to consider before excavation begins. Heaving from frost is less likely to occur in sandy soils than in clay soils but it is still important to factor everything into the equation.

Resources

Aeration Can Improve The Physical Properties of Soil.

More Excavation Pictures