resident ll +family + lodgers

HMO Licensing

i am a resident ll with 2 adult children. I have 2 lodgers. the house is 7 bedrooms 3 floors.
I wish to take a 3rd lodger.

I asked the local council where i stand regarding hmo if i take a third lodger.

They told me i would have 6 people in the house therefore i would need to be a licenced hmo.

I argued that myself and family count as 1 unit not 3 persons. therefore my family 1 unit plus the 2 lodgers i have plus the 1 i want to get equals 4. therefore i dont need to be licenced.

the council disagree and say we would be 6 persons. Who is correct.????????????????????

At the moment i am not an hmo therefore dont have to do anything. the minute i take 1 more in the council want 17 fire doors done, emergency lighting, zoned fire alarm in all rooms and corridors costing about 6 grand. thats a lot of money for 1 extra person.