
Stone walls, granite paving and bluestone banding combine to make an attractive long lasting project
Is your landscape designed for the long haul? Have you designed for future improvements? Have you considered ongoing maintenance in your planning and material selection? Have you considered life cycle replacement in your material selections? These are some of the questions, as Landscape Architects, we look at when designing projects for the long haul. For many of our larger residential clients and institutional clients cost is not the controlling factor when making decisions about materials. Many of them are interested in projects that will not only look good but stand the test of time. Natural stone is a great choice for your landscape that will stand the test of time. Natural stone has been the go to material for paving and walls for thousands of years. From Beach pebbles to granite slabs, natural stone rocks!
For your hard-scapes, which include terraces, walls, steps and even garden enclosures, it is essential to select materials that are high quality, durable and suitable for your climate and location. How the hard-scapes survive and weather overtime is an important consideration for when you are implementing a project or renovating your property. Well selected materials will, either develop wonderful patina and survive for many years, or disintegrate as weather and environmental conditions take their toll on the project. Landscape Architects will select materials that are good quality and will provide the best value for long term outdoor landscape installations.
The most important factor to consider when selecting proper stone materials is to use something that is tested and suitable for your climate. Most people don’t consider reviewing the USDA Zone chart when selecting paving materials. However, it can be a valuable tool to understand what conditions the stone will be subjected to. For example, most sandstones are not suitable for New England because of our freeze thaw cycle that causes water to gradually infiltrate the stone and make it flake and crack overtime. Tennessee Crab Orchard stone is a beautiful red colored sandstone but when used in Connecticut will spall and disintegrate within a matter of years. However, in the south the stone works wonderfully. It is generally a good rule of thumb not to choose a stone which comes from a climate warmer than where it is going to be used.
Quarried stones such as Bluestone, Granite, Limestone, Marble, Sandstone, Quartzite and Slate are durable, natural materials and that are very versatile. They can be used for paving applications, curbing, walls, and steps and decorative elements. These natural stones are readily available worldwide and come in a wide range of colors, textures and can be cut into any size or shape.
Beyond the typical quarried stone there are a broad range of other stones available. River rocks or beach pebbles are smooth rounded stones that can be used for pebble mosaic walks or as decorative gravel. Cobble stones are larger rough quarried stones that have many uses. There are ancient remains of cobbled streets from Roman times in Europe. Granite setts (Belgian block) are used today for paving and curbing. These Blocks were originally used as ballast in ships in the 18th and 19th century. The Belgium block were used to pave the streets of Boston and New York city and have been extant since the 18th century. Cobbles and Belgium blocks can be set in sand, stonedust or concrete depending on the location and their purpose. Natural stone is the best choice for a paving installation that will perform over the long haul.
Proper setting and maintenance is essential to having the installation stand the test of time. In cold climates where freeze thaw and snow are a problem that must be taken into consideration and designed for. Some of these materials that are susceptible to extreme moisture damage such as sandstone, limestone & slate in the Northeast are best avoided for paving applications. Proper base preparation and making sure water cannot sit under the pavement will prevent cracking and degradation of the stone over time. Properly pitching the pavement to make sure water doesn’t sit on the surface is very important.

Poorly design plaza showing the compounded effects of bad maintenance and design can have on stone over time.
We worked on a church project where the stone plaza failed after only 20 years. Upon further investigation several problems were uncovered which contributed to the early demise of this installation. There was insufficient gravel under the slab causing it to hold moisture, the slab was too thin, the concrete was poorly mixed, and placement of the steel within was incorrect. These caused the concrete slab to fail. The pitch on the whole plaza was so shallow that the natural cleft in the stone created puddles, allowing moisture to seep into the stone. These issues were compounded by the fact that client used heavy amounts of natural salt as a deicer on the sedimentary stone which caused it to flake more quickly. The plaza was redesigned to mimic the original design but provided a better draining base, more pitch and used a granite to allow for more durability and better drainage. In the end the project was a success using the right materials for the job.
Structures like walls, piers or steps can also be made from a wide range of natural stone or quarried stone. With proper design and construction these structure will last indefinitely. The landscape of New England is lined with simple stone walls, constructed from fieldstones, farmers removed the rocks from the fields to allow them to be plowed and used for grazing. Many of these walls have survived for centuries without sophisticated footings or being held together by concrete. The proper placement of larger stones underground and the arrangement of the stones are all that keep the wall together. These types of walls are a work of art, creating a complex three-dimensional form from a collection of stones of various sizes and shapes under the hand of a skilled mason.
For a landscape that stands the test of time using natural stone is a must. Not sure where to begin or what stone to use? Call Rock Spring Design Group at 203-581-5715 or email us info@rockspringdesign.comfor a free one hour consultation to discuss your upcoming landscape project.