**Draining the pipes is usually a temporary fix. A proper water hammer arrester is the lasting fix—if water hammer is indeed the cause.**

Older plumbing sometimes has capped pipe sections that trap air to cushion sudden pressure changes. Draining can replenish that air, but it gradually dissolves into the water. Your brief improvement is consistent with this, though it doesn’t prove you have those chambers. Modern arresters keep their air cushion separated from the water so they don’t become waterlogged. [Sioux Chief explanation](https://www.siouxchief.com/Products/SuperDetails/19)

I’d proceed in this order:

1. **Check whether it’s hammer or valve chatter.** Close the faucet slowly, then quickly. Noise primarily after a quick closure points toward water hammer. A buzzing or rapid vibration as the toilet finishes filling can also come from its fill valve or supply shutoff valve. If one toilet is the main culprit, cleaning or replacing its fill valve according to the manufacturer’s instructions is a reasonable DIY step. [Fluidmaster’s noise guide](https://www.fluidmasteruk.com/sounds-of-the-cistern-system-what-do-they-mean/)

2. **Measure your water pressure.** Attach a hose-thread pressure gauge to a hose bib supplied by the same regulated plumbing as the house, with all fixtures off. If it exceeds **80 psi—about 5.5 bar—address the pressure regulator first**. Partially closing the main shutoff reduces flow but does not reduce the pressure when everything is off. [Watts pressure guidance](https://www.watts.com/resources/references-tools/waterpressurereducingvalvesfaq)

3. **For confirmed hammer, fit an arrester near the valve causing it.** Screw-on models can fit between a fixture’s shutoff valve and flexible supply hose, often allowing installation without cutting pipe. Choose one with the correct connections and follow its placement instructions. Shut off the supply and relieve pressure before disconnecting anything; check carefully for leaks afterward. An arrester at the main inlet may do little for a distant fixture. [Arrester placement and operation](https://www.siouxchief.com/Products/SuperDetails/19)

4. **Check accessible pipe supports.** Loose pipes can amplify the noise by striking framing. Secure them with supports suitable for the pipe material, without overtightening.

Given that both faucets and the toilet trigger it, **checking house pressure first, then installing an arrester close to the worst offending fixture**, is a sensible next move.