I have just come back from holiday and the water pressure to the house has dropped so much that you can only have 2 taps on anywhere in the house or they stop completely please can any one help with this problem

This is a volume problem, pure and simple. Pump or city water? How old is your house? What type of pipes do you have? If on city water call them and ask if any work on the main was done while you were gone, also ask what the main PSI is out in the street. Do you have a PRV,(Pressure Reducing Valve) installed if on city water? Let me know, tom