Housing Report -Spouse Visa

Hi Guys,

My brother recently got married in India and he needs to apply for his wife's visa. At the current time we live jointly with our parents in 4 Bedroom house. I have read some rules regarding overcrowding and I think we are ok in this regard as a 4 bed house can have up to 7.5 people if all the bedrooms are above 50 sq ft and we will all be together 6.5 people.

Now I was wondering whether my brother will need a housing report done from a surveyor or can we do without?