When you think about building a pool, testing the soil may be the last thing on your mind. You may not know that soil conditions can turn a pool building project into a disaster and cost you a lot of money. You need to have the soil tested by a geotechnical engineer. The reports they provide help keep your project on track.
Why is soil type so important?
It’s important that your pool is stable. You do not want it to move over time, potentially resulting in the need for costly restoration and repairs. Soil type is important when considering stability because expansive soils can lead to a significant amount of ground movement over time. Clay in soil can cause expansion because the molecules in the clay retain water causing them to increase in size. There are five levels of expansiveness in soil, from non-expansive to very high expansive.
Soil testing also identifies other potential problems. If a high level of salt is detected this can react with any water present to cause metal structures to erode. Organic substances can prevent your pool from settling correctly, so they need to be removed before construction begins.
The ideal situation is that soil is suitable for the building of your pool and that the type of soil is consistent around the entire area where the pool is being built. Even if the soil is less than perfect, you may still be able to build a pool but you need to check the soil test results and make sure any recommendations are used in the final plans.
Soil reactivity classes and how they affect your pool building project
There are several different types of soil, classed by their reactivity level. Classes include:
A – non-reactive, movement unlikely.
S – Slight movement possible.
M – Moderate amount of movement possible.
H – High levels of movement could occur.
E – Extreme levels of ground movement possible.
P – A structural engineer should be consulted before building as moisture could cause extreme amounts of ground movement.
Looking at these different classes of soil, you can see why it’s important to know about the type of soil you are building on. It can make a big difference to how successful your pool building project is.
How is soil tested?
- Soil testing is not something that you can do yourself. You need to hire a qualified geotechnical engineer to do the work for you. They examine the area of land where you are going to build your pool, and take note of the characteristics of the soil. This is not the end of the story.
- Samples of soil are taken from the area, and sent away to the laboratory for testing. Samples of groundwater are also taken, as groundwater can play an important role in the stability of the ground, if levels are high.
- Once the results of the testing are known, the geotechnical engineer analyses them and produces a soil testing report. The report includes:
- – The results of the testing.
- – Details of what these results mean for your pool building project.
- – Recommendations of steps to be taken, to avoid potential issues.
This report is an important document. It’s used to help designers and construction professionals to design and plan the building of your pool.
Can problems with expansive soil be fixed?
If the soil testing report reveals that you have a problem with expansive soil, this does not necessarily mean that you cannot build your pool. There are methods that can be used to solve this type of problem. These methods include wetting the ground before construction starts, so that any expansion takes place then, and there is less chance of expansion once the pool has been built. Alternatively, it may be recommended that you remove some of the upper soil levels and replace them with non-expansive material.
Of course, there is always the chance that you may be advised not create a pool in the planned area. You should always pay attention to these recommendations as not doing so could mean that your pool is not stable and has to be removed. This will end up costing you a lot of money that you were not expecting to spend. You may also find that you need to have a building permit to complete your project. Usually, you will not be able to get this without having a soil testing report that includes information about building safely on the site.
If you are tempted to cut costs and take a chance that the soil condition will not affect the building of your pool, think again. Soil testing is never going to be the most glamourous part of pool construction, but it’s one of the most important. Soil condition can affect every aspect of pool design, so never ignore it.