It depends. You could do something as simple as governing down the water supply in each shed. Try turning the stop taps down and see if that makes a difference. It may alter flow into the sheds but should not affect the pressure.
I assume its one pipe with a tee out for each shed or one tee for sheds and when above ground the main splits to feed each shed. And outside goes onto house
Failing that dig up the main befor the tee or tees to the sheds, and route a separt main to the house.
It all depends on what the layout is.
What your trying to do is stop the sheds from pinching all the water. By adjusting the stop taps all your doing is trying to balance the system like a Plumber would a central heating system.
If the sheds are production sheds it depends on water use and at what time the peak use is. You may be able to use something like an auto balancing valve that opens up to let the sheds use water at peak times and closes down when they are not, directing more water back to the house.
It all depends what you have got.
Thanks.
