Matt;

Isn't that's kinda like asking: How does a car work?...in twenty words or less...

....if you have a battery powered house, you clearly need to take some initiative in edumacating yourself on all there is to know about the care and feeding of lead-acid batteries (and there's a surprising lot), especially, and not limited to, venting the hydrogen released when you charge one (to prevent you from seeing your envirohaus do its impression of maybe the Hindenberg...not he flying away part, but the blowing up part!)....and these questions are sortof beyond the scope of this forum...but I will try to get you started...

I would suggest you fully charge them, let them sit (without discharge) for an hour, then make an accurate hydrometer measurement (taking into account the temperature factors), and another hydrometer measurement one after another hour(to verify the first), if hydrometer measurements are similar, indicating an accurate voltage measurement (unaffected by surface charge) can be taken, make an accurate voltage measurement of each cell, and make your own reference chart...then do hydrometer checks monthly, and compare with previous readings to monitor degradation of cells.

see also: http://www.intelab.com/swem/elecramb.htm

(se also link there for a very informative battery site)

Charged Up Cheers