I have used SnowRoof and ElastOSeal. Both work okay and are non-toxic. The big problem is that they are soft and will abrade over time. The abrading won't cause leaks but will need to be retouched to keep a nice appearance.

: I am currently building a skin on frame in my attached basement/garage. I
: would like to kill the weave and paint with anything that will not affect
: the health of my wife and cat. I have a respirator but do not want my
: family to have to wear them. (Do they make them for cats?) The half pint
: of marine enamel that I used to paint the frame was bad enough. I know
: that latex paints are not technically waterproof but was wondering if
: anybody has used an industrial/flexable latex coating or anything else
: that might be suitable for my needs. I do not mind a higher maitanence
: tradeoff for a less toxic working environment. I can not work outside
: until the spring due to the low temp in Victoria, B.C. at this time of
: year.

: Thanks in Advance, Curtis