I have a relatively new sourdough starter from the BB.  When making basic sourdough, it seems to expand correctly on day 1.  But then when actually making the bread, it loses its rising power.  And the dough gets very, very soft, expanding sideways but not really rising.  The starter seems fine as it made an okay BB whole wheat sourdough bread, though the last rise was somewhat weak.  Also the starter does not rise during the week in the refrig, but postings suggest that is no problem.  Any thoughts?  I really want a good basic sourdough, not just a wheat one.

How warm is your room where you are doing the rising this time of year?

I am rising the bread in my oven with the oven light on.  I typically do a quick pre heat for 1 minute to warm the oven and then rely on the oven light to keep it warm.  When I checked, it was typically 70-75 degrees.  I was thinking that was warm enough as the sourdough starter rises in the time spans given in the BB under these conditions, but at the longer time span.

I would just hang in there, my starter does the same thing every now and then.  Temperature is a strong factor of speed and kick.  I wouldn’t worry much about it… been waiting 8 hours for my Basic Heart Bread with sourdough tonight.