Question
Sean
I plan on having a patio installed of interlocking pavers-Approximate 20 x 25-I live in the NYC area and some of the contractors want to install the pavers on concrete and some on a base of compacted sand and aggregate-I thought the sand base is what the manuf. advises for drainage reasons -what is your opinion--Thank You

Answer
Tom:
Without knowing your exact soil conditions, proposed usage, and drainage patterns through this area I can not give you my absolute opinion. However, in most cases where the pavers are only going to support pedestrian and vehicular traffic of a residential nature and will not be subject to any other unusual circumstances then generally speaking an aggregate base is sufficient. However, if your soils are known for heaving from frost, of the site has drainage issues or if there will be heavy truck or delivery traffic you may want a more substantial base material and concrete may be the best alternative.

Sorry I can not be more definitive without site knowledge.

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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