Question
What are the similarities and differences in installing pavers and flagstone.  What are any additional options or variations to certain steps of the installation process?

Answer
First off, 'pavers' as a word can be applied to many materials that may be used as a hard surface materials. 'Pavers' is a generic term. For the purposes of this response I will assume you are asking me to compare clay or concrete pavers (shaped like typical bricks) to natural stone shaped in random rectangles.

This is a rather broad question...but here goes.
The similarities are that both may be laid with or without mortar. Both will last a long time. Both are simple to install, The cost can be relatively similar or very different.

Pavers are the easiest to install in most aspects because you don't have to fit them together carefully, you just place them adjacent to each other and keep moving, patterns are typically relatively simple. Flag stones however, may take some careful alignments and cutting or chipping of stones. If they were not pre cut this can become very tedious. Like tiles, flagstone require thought to insure the pattern works and aligns with the surrounding edges.
Pavers typically range in the $4 to $8 per sf. range unless they are mortared in place. While flag stones usually start at $8  and can go well over $20 per sf when mortared and grouted in place.
Flag stones and clay or concrete pavers both come in many colors. Flag stones also come in varying thicknesses which may be important when covering an old patio. Most clay/brick pavers are fairly consistent in thickness between 2 and 3 inches (although there are some specially made pavers for applications requiring thinner pieces).

As for the installation process both can be applied by laying a 3-4" thick concrete or compacted gravel base and applying a bedding layer of sand of about an inch and then placing the stones or pavers. Both can be laid by pouring a concrete slab and then a mortar bed and placing them on/in the mortar. The difference here would be you would not typically grout the joints in pavers as you would in flag stone. Although if you wanted to you could put grout joints in pavers, but that would be extremely unusual.
Lastly flagstones or pavers if set in mortar should be sealed to prevent water intrusion which could freeze and pop loose the paver/stone.  All concrete pavers must be sealed to insure color does not fade. This is not required in a natural stone or clay products but still a good idea.

Well, that is as brief as I can make it.
Hope that helps.


Sean J Murphy, LA,ISA, LEED AP
Please check out my blogs and articles on landscape topics like this on my websites.
http://www.seanjmurphy.com
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