Calculating the Amount of Primer Needed

Primer: You can get in the ballpark by painting a test area with a measured amount of primer and then noting how much area the primer covers.

For example, say you've measured out 600 ml of primer and have determined that this amount covers an area of 5 m². As your total pipe area is about 720 m², you'll need on the order of

720 m² / (5 m²/600 ml) = 86.4 litres of primer to coat your pipes.

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Tape: How much does (or should) each turn overlap the previous one?

32.8m^2 per 3.8 litres of primer N.B. 3.8 litres is approximately 1 gallon

by sipmle math we see that the amount required is (720m^2 x 3.8ltr)/32.8m^2

= 83.4 litre.

cant fig it out at the moment nothing relating to the tape width

Hi....firstly specify the type of primer you wish to apply. Then ask the paint company to send you its technical literature. You'll find the coverage mentioned therein. This will however vary depending on surface roughness / preparation, method of application e.g. spray or brush.

Coating and wrapping is best done and described in american spec AWWA C203.

It takes 2 coats at least to prime something good. I just figure it takes as much as I use .