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Sizing Calculators

Need a sizing calculator?

Don't Worry, I've got your back.

These Sizing Calculators conform to British Water Guides and Building Regulations. Working out the size of septic tank, treatment plant or drainage field just got a lot easier!

My Sizing Calculators are free for anyone to download and use. Unfortunately I don't have time to help you over the phone with any of them. Seeking professional advise from your local installer or supplier regarding the size of a sewage treatment plant is however advised.

Sewage Treatment

This simple treatment plant size calculator is aimed to make it easy to convert the number of bedrooms in a house into a maximum population for treatment sizing purposes. The multiple house section allows you to size for a housing development.


Drainage Fields

Performing the calculation necessary for the design and installation of a drainage field just got a lot easier with this simple but powerful excel size calculator. Conducting a percolation test is the first step, this calculator guides you through the steps from the start, leaving you with a design to follow.


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