Iain is correct.
I noticed this earlier & thought it strange.
If it's just you who is applying, then a room in a shared house might, just might,
be acceptable to the ECO.
HOWEVER.... if you are bringing the children..... it will NOT be acceptable.
The ECO will be looking for suitable accomodation.... meaning an least a bedroom
for the children (maybe 2 bedrooms depending on age), and a bedroom for you
and your husband.
Also, I would have thought, non-shared bathroom & kitchen.
Moving to a BIGGER room is NOT the solution.
You need to address this BEFORE submitting your spouse visa application.
Otherwise it is doomed to failure.