How to increase the water pressure in a house ?

You will probably want to look for the pressure switch. it will be a 3"x2" gray box, attached to the pipe or pressure tank, and will have two fairly large wires coming off it. inside this box is a set screw, tall screw with a locknut on it usually. check inside the cover for directions for adjustment with this screw make sure you test you pressure tank air psi and make it 2 lbs lower than your lowest pressure set point ask someone that has made these adjustments to help the voltage is high and the settings are critical

Try to locate the shut off for the entire house. It should be located near an outside wall and usually has a regulator located near it. Make sure that the main shutoff is fully opened. Also check the shut off at the meter. It should be fully opened as well. If neither of these solves the problem, then you could increase the pressure at the regulator. You will first need to buy a pressure tester though. They can be purchased at any home center. You don't want to randomly change the regulator setting without having a way to monitor the changes. Factory setting on a regulator is 50 psi by the way.

You can go to the pressure tank and there should be a pressure switch attached at the pipe. You can turn it up right there. You have to be careful though because you're dealing with electrical - don't want to get zapped.

Why not buy a water pressure machine. You know the machine where you plug in and spray water with an engine.

there is usually a valve to turn the water pressure up.you just have to find it.

Sometimes..........but being that old are your pipes clean, I've taken 40year old ones apart and they are just like our veins....totally plugged....except for a hole about 1/16" of space for water,,,,,,,,,it looks just like white lard, soap and rust. All the best to you