Building on Clay: Do You Need a Shrink/Swell Soil Test?
If you're building a new structure on unused land that is mainly composed of clay, then you need to do some soil testing. These tests establish the suitability of the land to hold your structure.
Clay can be a problem soil for builders. Before you start on the project, you should have a shrink/swell test done on the ground. Why is this necessary and what does it tell you?
What's the Problem With Clay?
Clay can be a tricky soil to work with. While some clay soils naturally create a stable foundation, others can be too unstable to give the right amount of building support. Clay is an expansive soil. This means that it changes shape according to the conditions around it. For example, clay can shrink a lot when it is dry and expand a lot when it is wet.
While some other soils also do this, clay can produce extreme reactions if it contains a lot of specific minerals. If the clay's mineral content gives it a high shrink/swell potential, then the ground will move in extremes of dryness or wetness. This makes the ground under your structure potentially unstable.
What Does a Shrink/Swell Test Tell You?
The first thing a shrink/swell test tells you is whether the clay you'll build on is a problem. If the clay scores low on the test, then everything may be fine. If it scores high enough to raise a red flag, then you know the ground isn't suitable for a standard build.
If you build on unstable clay without compensating for shrink/swell factors, then the structure you put up will be fine to start with. However, as time passes and the clay shifts and changes shape, it may not be able to hold the structure steady. Movements in the ground could cause foundation damage like subsidence and heave. So, this test basically lets you know whether you need to make your foundations deeper or stronger. If you don't know how to handle this, you may want to hire a structural engineer to draw up suitable plans for you.
A soil test may be a condition of your planning permission, so you need to get this test done quickly. For quick and effective results, hire a soil testing company who have geotechnical experience. They can take a sample of your soil and put it through a shrink/swell stress test to see how it reacts.
