Leaseholders and service charge on different sized flats?

The building split into 15 different sized flats is managed by a board of directors from the leaseholders. It has worked reasonably well, but now that the building is in need of updating and also some hefty repairs (roof) the directors have decided that they will change the way that the service charge is paid.

It was on percentage, and they want to make it an equal split – obviously there have been objections so backed down on that, and now want the service charge on the original percentages and the repair fund to be split equally as there is a bit of a weird thought that all flats use the building equally – they are from 1 beds to 3 bed penthouses (2 of those).

Major works have already been done to the roof with no S20 (if it’s self-managed do they need to issue this?) and no tender process, it was the people who usually do the repairs instructed.

4 directors from 3 different flats are currently making these decisions, one director has disagreed so the letters are going out without his name on it.

A loan was taken out by the directors in the name of the building to fund some works last year.

I can’t help but thinking that this is not quite right but finding it hard to word.

Elizabeth