Pool Base Material - Vermiculite & Portland Cement

Pool Base Packages
Vermiculite Bags
Pre-Mix Bags

The purpose of the swimming pool base is to provide a smooth surface for the swimming pool liner. A smooth surface is less abrasive on the pool liner and makes it easier to keep the swimming pool clean. There are four choices to use for the pool base.

	Sand is the most economical and works well in play swimming pools that do not have a steep slope. The amount needed will vary by pool size. The sand should be mason's quality and spread about 1"- 2" thick. However it does not provide a pool floor without foot prints and impressions.
	The most common used swimming pool base throughout the years has been a mixture of sand and portland cement. Portland cement is available from your local hardware store and can be mixed with sand to form a hard floor.
	Vermiculite can be purchased in 4 cubic foot (average weight 20lbs - 30lbs) that must be mixed with Portland cement or in 42lb bags that is already mixed with Portland cement. The pre-mix is also known as pool-crete. The Vermiculite & Portland is mixed with water using a paddle mixer or cement mixer.

Additional mixing information is provided in the Inground Swimming Pool Installation Manual.

The actual amount of material needed will vary depending on the dig and thickness of the swimming pool base used. This table can be used as a guide. It is based on a 2" thick swimming pool base. The sand/portland mix is generally the best choice for most homeowners. The Portland/vermiculite or Pre-mix should be used for high water table areas and hard freeze areas.

Pool Size	Sand (Tons) / Portland*	Portland* / Vermiculite	Pre-Mix Bags
12 x 24	3 / 7	6 / 13	26
14 x 28	4 / 10	8 / 16	32
16 x 32	6 / 13	13 / 25	50
16 x 36	7 / 16	16 / 30	60
18 x 36	8 / 17	17 / 34	65
20 x 40	9 / 20	19 / 38	75
24 x 44	10 / 25	20 / 40	80
16 x 41 x 26	9 / 20	19 / 38	75
20 x 45 x 30	12 / 26	25 / 50	100
Pool Base Packages Vermiculite Bags Pre-Mix Bags *94 lb bags of portland cement

When using pre-mix or portland/vermiculite mix, over mixing will reduce the coverage when applied to the swimming pool floor.