How To Stop Water Hammer In Taps. I don't think the number of and position of tee's will cause water hammer, from what you describe it is not water hammer, but sudden water stop, this could be because the restictor has not been used on the toilet ballvalve, or a mixertap / showermixer is not up to standerds. Water pipes make a banging noise when taps are turned on.
Problem excessive water pressure causes loose pipes to bang against wall studs. Loud banging noises when you turn a faucet on or off is caused by water hammer. Open all the cold water faucets, start with the highest faucet (2nd or 3rd floor) and work to your lowest faucet (first or basement floor).
If your pressure is running near 100 psi, then it’s likely the cause of your issue.
Modern pipework systems are fitted with air chambers which are designed to prevent water hammer from occurring. This is usually caused by the entry of water into the air chamber, thus making the air chamber ineffective at protecting the valve. Best to experiment by closing it say ¼ turn at a time and checking the taps before you try. Solution install anti hammer tap valve or hammer relief valve.