Pounds per square foot to inches of water converter on this page calculates how many inches of water are in 'X' pounds per square foot (where 'X' is the number of pounds per square foot to convert to inches of water). In order to convert a value from pounds per square foot to inches of water (from psf to inH2O) type the number of psf to be converted to inH2O and then click on the 'convert' button.