The Schundler Company
10 Central Street
Nahant, MA 01908
732-287-2244 www.schundler.com


For many years homeowners have struggled with how to install above ground pools in their backyards. To have a flat and level surface, grass and stones have to be removed, and then heavy sand is carried into the backyard and leveled. The problem with sand is that it is heavy, hard to use, and difficult to remove when the pool is dismantled.

Schundler Pool Base has been used for over thirty-five years to help make the installation of above ground pools easier, safer, and more environmentally friendly.

Basic Advantages

Schundler Pool Base and/or Crystal Cushion should be used for many reasons:

What Is It?

Essentially Schundler Pool Base is regular vermiculite---a naturally occurring mineral which is expanded at 1200 F and used in a variety of industrial and commercial applications. When used in above ground pools it usually is not mixed with portland cement, although some pool installers will install vermiculite concrete bottoms just like those installed in in-ground vinyl lined pools (see the other pages on this section of our web site).

Schundler Crystal Cushion (sold only in certain states) is made from perlite, a naturally occurring volcanic rock expanded at 1800 F. Some installers and home-owners like to use perlite which is dustier than vermiculite, but when tamped can provide a little more support. It is dustier than vermiculite, and is not available in many locations.

Installation and Coverage Data


  1. Make sure all stones and other foreign objects are removed and surface is well packed.
  2. Check with your pool dealer for information about the coving areas and the recommended depth of Pool Base.
  3. Pour, rake, and level Schundler Pool Base or Schundler Crystal Cushion (never use less than 2 inches!); then mist with water before installing liner. With Crystal Cushion, don't just "mist" the perlite, make it quite damp so that it can be "tamped" or flattened with more force than with a vermiculite bottom.
Approximate Coverage Data (based on 16 lbs.---3.7 to 4.0 CF--bags of Schundler V+16 Pool Base (or Crystal Cushion) or Schundler Ultra Mix (pre-blended vermiculite and portland cement):

General Pool Sizes Bags of V+16 Pool Base (or Crystal Cushion)
Needed For
Bags of Ultra Mix
Needed For
2"3"4"2" Hard Bottom
12' Diameter Round or 10' by 15' Oval681112
15' Diameter Round or 12' by 18' Oval9121618
18' Diameter Round or 14' by 21' Oval12182424
21' Diameter Round or 16' by 24' Oval17253334
24' Diameter Round or 16' by 32' Oval21324342

(Instead of using just vermiculite, some people prefer to put a vermiculite concrete hard bottom under above ground pools. To do this, use either the coverage chart for 2" to determine how many bags of Schundler V+16 Pool Base you need, and mix one bag of portland cement (94 lbs.) with every two bags of vermiculite, or use the Ultra Mix chart. For mixing and troweling instructions, see our "Contractor's Guide")

We hope this brief description of Schundler Pool Base is helpful. For more information, please call or contact your local dealer or:

The Schundler Company
10 Central Street, Nahant, MA 01908
732-287-2244 or www.schundler.com

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