Start by narrowing it down: is it one faucet or showerhead, or every fixture in the house? Single-fixture weak flow in DFW is almost always mineral buildup — hard water leaves scale inside aerators and showerhead nozzles that gradually chokes the flow. It's a cheap, fast fix: unscrew the aerator or showerhead, soak it in vinegar or simply replace it, and pressure is usually back to normal immediately.
Whole-house low pressure is a different problem with three likely causes. A pressure-reducing valve (PRV) at the point where the city line enters your home can fail over time, and when it does, pressure at every fixture drops together. Older homes with galvanized steel supply pipes can develop internal corrosion and mineral scale that narrows the pipe's usable diameter over decades — the pipe looks fine from outside but is effectively clogged from the inside, and this typically gets worse gradually rather than all at once. Less dramatically, the main shutoff valve or a secondary valve somewhere in the system may simply be partially closed, sometimes after other work was done on the house.
Normal residential water pressure runs roughly 40-80 PSI; we test yours with a gauge at an outdoor spigot to confirm there's actually a problem and rule out the city supply. If the cause turns out to be a hidden leak reducing pressure elsewhere in the system, or corroded pipe that needs replacing, those are separate jobs we can quote once we've pinpointed the source.