Hello A small bit of back ground. Roadworks have been completed outside my house. In doing so they disturbed the mains water supply, which in turn has dumped a lot of rusty looking sludge into my water supply. This is now running clear, but i very poor water flow to most of my taps. The water provider has contracted a plumbing firm to rectify, but so far, after two different plumbers and four days later we still have issues. There is no issue with the flow ahead of the unvented system, as one of the bathroom taps is plumbed in before the airing cupboard. This is super powerful. However everything after the airing cupboard is poor, worse upstairs than down. When you open a tap, the initial flow looks positive, however within 20 seconds it reduces, and depending on the location around the house, it runs okay'ish or literally slows to not a lot. This is for both hot and cold. So far they have taken pipes apart in the airing cupboard, plus replaced a valve (I think the PRV - my understand it this value "balances the pressure between hot and cold"??). We are due another 'team' to flush the mains, and dismantle our pipework, which seems dramatic, and a bit concerning. Logic says to me, that we have good flow up to the airing cupboard, we have good flow to the taps, initially, so I am not sure this is a blockage?? Any support / comments would be appreciated.