Cold and hot shower shocks - The least intrusive way to fix this

IF YOUR SYSTEM IS A GRAVITY FEED ONE YOU NEED TO HAVE HEADER PRESSURE, SAY IF YOUR COLD WATER TANK IS IN THE LOFT WHICH FEEDS YOUR HOT WATER TANK YOU MAY HAVE SAY 2M OF HEADER PRESSURE THEN THINK OF WERE YOUR SHOWER HEAD IS IT MAY ONLY HAVE 1M OF HEADER PRESSURE, A LOT OF PEOPLE WOULD THINK ITS THE PRESSURE TO TAP OR SHOWER CONTROL BUTS ITS TO THE SHOWER HEAD

Do you have a gravity fed system with tank or do you have a combi boiler? it is more likely to be as above, when you use the shower the more you hold the head up the less pressure you have forcing the water out as you are nearing the tank in the loft. Also with someone else using a tap or flushing the toilet there is more pressure going to that as they will run full bore of the pipe and not restricted like the shower so they will cause the sudden fluctuations in temperature as they draw the water from the shower. The best and log term solution will be to install an electric-power combined shower or a shower pump, but only if the tank in the loft is big enough to cope, other wise if you have mains water supply near the bathroom you can have an electric shower.