It is becoming more and more popular in landscaping to use a permeable base for the construction of non-permeable paving stones. This is the new common foundation laying method these days. So, in this blog, we will give you a brief description of the permeable base, explain its advantages and disadvantages as well as its best uses.
If you haven’t already, we invite you to start reading on this subject with the article What is a permeable base?
The needs of a foundation
First, when we talk about paving stones and their base, we have two very important points to remember. The foundation must have a load capacity adequate for its operation and it must be made of draining materials. For example, a parking lot will have a different foundation than a patio in your yard, because each has different functions. On the other hand, no matter the usefulness of your installed paving stone, its foundation must always be built using draining materials. This is why more and more, contractors and entrepreneurs like TRASINI Group are using the permeable base.
Brief description of the permeable base
As the word permeable says, the base is draining. We use 1”-1/2” clean stone for the sub-base, 3/4” clean stone for the foundation and 1/4”-1/8” clean stone for the bedding to allow water to drain easily. This is different from the traditional base which uses crushed materials such as 0”-3/4”.
For more information on the differences between traditional base and permeable base, go read What is a permeable base ?.
Advantages and disadvantages of permeable base
To see if the permeable base is useful, we will present its advantages and disadvantages.
The advantages
First, as mentioned above, the permeable base is draining. This allows water to filter and not accumulate in the foundation of the base, which helps minimize frost movement during the winter.
Secondly, due to the clean angular stone used in the foundation, the possibility of “wash-out” of the materials is less likely. A wash-out is the fact that the fine materials of the crushed stone slip into the small holes created by the movement of the soils. This mishap happens especially in raised patios and steps due to the spaces and holes of the low walls, so the use of the permeable base is ideal for these. The angular shape of the clean stone allows the foundation not to create these movements since each stone is nested one inside the other.
Additionally, the material used minimizes weed and ant infestation if the sides are well covered with geotextile membranes.
Finally, this base is also easier to work with, because the compaction is not as intense as a traditional base and it works well even during a period of rain and snow.
Disadvantages of the permeable base
On the downside, there would be the possibility of horizontal drift of the paver. The way to counter this is by reinforcing the edges that hold the sides of the paver. Instead of putting nails every 18 or 24 inches, we put them every 8 or 12 inches.
