Some food related items such as bacon grease or oil poured down the drain can solidify once inside the pipe. It loses more pressure from the home to the faucet. But, keep in mind, with a regular storage tank type water heater, if you increase the volume of water flowing through your home, you water heater tank will empty faster, unless you have new water savers on your faucets. The water pressure, from a water company source, through the lines, is very high. The smaller the space, the lower the pressure because less water moves through it.

Some chemicals are too potent to be sold over the counter to the public. Many over the counter chemicals may work to break down and flush out mineral and food buildup. If this does not work, your local plumber can buy stronger chemicals or use a snake.

If the pipe is too small, a professional can replace with a larger size. The space can be too small because of the size of the pipe or debris build up. Sometimes a blockage can be a developing problem. This can mean a great hot shower, but it won't last as long.

Water loses its pressure between the main line and your home.