Methods for installing patios in New Hampshire have evolved greatly over the past several decades.
Unlike other parts of the country, our region is subject to freeze-thaw cycles and silty soils that tend to drain slowly. Installing a patio base that will be stable and not hold water is critical here in New Hampshire.
Permeable paver design has swept the hardscaping industry by storm – offering a better strategy than traditional patio base construction for dealing with on-site water issues while providing a stable paver base that will last for many years.
What are permeable pavers?
Permeable pavers look similar to any other concrete paving stone, except they have wider joints between them that allow for water to percolate down between them. The superiority of permeable pavement system is not so much in the paver but in how the base is constructed.
A permeable paver design uses layers of compacted, free-draining stone. Water is pulled away from the surface and allowed to drain back into the ground or be channeled away.
Different types of permeable patios
True permeable patios are built as in the diagram above. Permeable paver design is recognized by NH building codes as “pervious pavement.” This is useful when the square footage allotment of non-pervious structures are limited, as in small shoreline building lots. Installing a permeable paver driveway means that the house footprint can be bigger.
Hybrid permeable patios have a similar base construction to permeable patios, but a hybrid pavement system uses a conventional concrete paving stone filled with polymer joint sand. It is not a true permeable pavement. It has the the superior freeze-thaw protection of the free-draining benefit of the permeable base, with the maintenance-free benefit of a standard paver installation.
The Hybrid Pavement System
How does Groundhog Landscaping install permeable paver patios?
Experience has shown us – as does this study by the University of New Hampshire – that the free-draining stone used in the paver joints of true permeable pavement tends to fill with sand and organic material over time, limiting the ability of water to percolate down through.
At Groundhog Landscaping, we will install a true permeable patio, walkway, or driveway when these specifications are required; however – in most residential applications – we prefer to use a the hybrid pavement system: installing a traditional paver with polymer joint sand on a true permeable system base.