When trying to increase your shower pressure, will replacing even a little of the 1/2" run with 3/4" do any good?

No, unless you change the entire run to 3/4", it won't change the capacity of the line. Without increased capacity, the pressure won't effectively change either (Pressure is different from flow rate, but in any event changing just a part of the run won't make any difference).

Increasing pipe size even all the way back to the water meter will not make a difference in your water PRESSURE...only increase water VOLUME available. Tell us what the problem here is? Is it that you always have low presrure or that you lose pressure/volume of water when someone else in the home uses water?

Back to you...

Mark

The experts are bang on. Increasing the pipe size won't give you more pressure. However, Is the shower the only fixture with low pressure? How's the rest of the house? Back to you, Tom