The Shieling, Wreay
Tel: +44 (0)1697 47 5369
Mobile: +44 (0) 7739 665 777
Fort Dauphin (614)
Tel: +261 (0) 20 92 21405
Mobile: +261 (0) 3302 21405
© Adriaan Mol,
May 7, 2004
Filter Casting Instructions
Bio-sand filter construction guidelines
Page 2 of 10
On the following pages, you will find an illustrated construction guide that takes you step-by-step through
the process of building your own bio-sand filter. Please note that you will first need a metal mould for the
improved round design. The advantage of the round over the rectangular filter is that it is structurally
stronger (less filters will crack). It also uses less cement and is therefore cheaper to build.
If you don’t have your own mould yet, you can easily build one using the illustrated mould construction
guide that is available from www.biosandfilter.org.
Much of the information in this document was collected by the author during a project that was financed
and implemented by Medair in Kenya, in 2000. Check www.medair.org for more information on the
humanitarian programmes implemented by this organisation.
This document, in part or in its entirety, may be copied, reproduced or adapted to meet local needs
without permission from the authors or publishers, provided credit is given to BioSandFilter.org and the
These provisions apply only provided the parts reproduced are distributed free or at cost – not for profit.
BioSandFilter.org would appreciate being sent a copy of any materials in which text or illustrations have
been adapted. For reproduction on commercial basis, permission must be first obtained from
BioSandFiler.org and the author(s) assume no responsibility for and make no warranty with respect to the