Stone Patios: What To Ask Before You Buy

A quirky garden sculpture sets a playful tone for this patio. 

Looking forward to family time this summer on your new stone patio? If you hire a contractor, make sure he gets the fundamentals right up front, so you won't have problems later on. After all, the focus should be on burgers and summer ales, right?  

There are three keys to a quality stone patio installation. Proper site preparation is the foundation for success, and as we say, quality stonework is in the mix of details. Good drainage can be the difference between an inviting outdoor living space and one that's slippery in icy weather. Let's talk about the specifics, based on our construction practices:

Site Preparation

  • the underlying soil compacted or undisturbed
  • 2" of gravel for good drainage
  • a concrete slab 3½" to 4" thick with fiberglass additive for extra strength
  • ½" rebar tied with steel wire in a 12" to 18" square grid to form a cage

The cage is suspended within the concrete slab rather than sitting on the bottom. Compared to the cost of the entire project. this additional reinforcement is inexpensive insurance against a cracked slab and damaged stonework. Below is an example of a cage used in a walkway installation:


Steel reinforcement in a walkway footing



  • flagstones set in a mortar bed ½" to ¾" thick 
  • elongated flagstones set perpendicular to the edge
  • mortar joints flat and consistent in size
  • flagstones evenly distributed in size and color
  • step risers between 7½" to 8" in height
  • step edges built from thicker flagstones
  • mortar joints wire brushed for a smooth finish

Built in 2001 and photographed in 2010, this stone patio still looks great today. 

Mortar joints on this patio are small, flat and consistent in size.

Step edges that are thicker and heavier are less likely to come loose and will withstand foot traffic better. (Flagstones refers to any flat stone, generally 1" to 3" thick used for patios and other flatwork.)
Drainage Requirements
Drainage requirements are site-specific and depend on the surrounding grade and existing structures. Some patios follow a simple flat plane, sloping in one direction only. Most require more complicated slopes in several directions such as the one pictured below:

A stone patio with a complicated drainage pattern

Steps on right lead to upper garden

Take care to choose individual stones that contribute to good drainage by examining them for twists and curves. Drainage patterns may require setting stones that twist incrementally in the needed direction.
Proper slope can call for as much as ¼" per foot but can sometimes be achieved with less. Of course, a flatter patio is better, as long as it drains completely and away from structures.

"Be sure your contractor takes the time to get the drainage right. It takes a little longer, but it's key to building a stone patio that lasts."

Enjoyable Outdoor Living

Keep these fundamentals in mind when choosing a stonemason or to avoid costly mistakes if you're doing it yourself. In the end, your patio should not only be beautiful but livable. It should be easy to move furniture around on, free from puddling and safety hazards and an investment that adds lasting value to your home.
Of course, doing your homework always pays. Choose an experienced stonemason with great references from people you trust. Look for one who has a solid reputation locally and offers a guarantee. European Stone Masonry LLC offers a lifetime guarantee on our stonework.
Most important, be sure your contractor is willing to take the time to get the drainage right. It takes a little longer, but it's key to building a stone patio that lasts. Now, will someone please pass me the ketchup.
Your comments and questions are welcome below.

Originally posted February 1, 2013