VERMICULITE
POOL BOTTOMS 		SCHUNDLER

PROBLEMS WITH
PACKED SAND 		SWIMMING POOL GUIDE
The Schundler Company
10 Central Street
Nahant, MA 01908
732-287-2244 www.schundler.com


SCHUNDLER V+16, ULTRA MIX AND ULTRA MIX II
Make Sand Pool Bottoms Obsolete!

Problems With Sand (Packed Sand) Pool Bottoms....

To help prevent accidents while diving, the pool industry changed it's regulations. Swimming pools are now constructed with steeper-pitched sidewalls and are made deeper than ever before.

With these new regulations and new construction practices, the use of sand as a base for vinyl-lined below grade pools can result in several common problems:

  1. In cases where the pitch of side walls has been too steep, the sand may eventually slide down.

  2. Packed sand is not porous. Changes in the water table can create hydrostatic pressures strong enough to break through the base. This can result in wash outs of the walls and floor, and lumps of sand settling under the liner distorting the pool bottom. To repair these problems, the water must be taken out to remove the liner, and then the sand has to be repacked before the liner can be replaced and the pool refilled.

  3. Pools with a sand base can be subject to foot prints and indentations.

  4. Because sand can be abrasive or too coarse, it tends to wear out vinyl liners. In contrast, Schundler Pool Bases are much softer and liners last longer.

  5. Packed sand offers no insulating properties, whereas Schundler Vermiculite Pool Bases are an insulating cement formulation.

Advantages of Schundler V+16, Ultra Mix and Ultra Mix II....

Aware of the serious short-comings of using packed sand as a base in vinyl lined swimming pool construction, The Schundler Company developed and introduced V+16 Pool Base and Ultra Mix. When mixed properly, these special vermiculite concretes offer several very important advantages:

  1. Schundler V+16 and Ultra Mix Pool Bases are much easier to apply to steep side walls, and will not wash away with changes in the water table.

  2. Schundler V+16 and Ultra Mix Bases form a monolithic cast. They are permanent and always remain in place.

  3. Schundler V+16 and Ultra Mix Bases form a porous concrete. When water tables and hydrostatic pressures increase, water can pass directly through the concrete without causing any damage to the pool walls or bottom. When water reaches the liner, it spreads laterally, and passes back out safely into the ground.

  4. Schundler Pool Bases become insulating concrete which insulates your pool water from the cold temperatures of the soil beneath it.

  5. With Schundler V+16 and Ultra Mix Pool Bases, the occurrence of footprints and indentations is rare. This enhances both the beauty and longevity of your pool

  6. There is some cushioning or resiliency when a swimmer's body accidentally strikes a Schundler Pool Bases--an important safety feature for both you and your family.


We hope the information given here will be helpful. The Schundler Company has been operating under the same name and in the same location since 1951. We developed the use of Schundler V+16 Pool Base in the swimming pool industry over 35 years ago, and we know it works well! In 1992, The Schundler Company developed Schundler Ultra Mix and Schundler Ultra Mix II, special pre-mixed blends of V+16 Vermiculite Pool Base and Portland cement and special additives. We hope you will use one of these products in your pool and that you wil enjoy it for many, many years!

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