Moving water tanks for additional bathroom

Hi
I'm working on updating my old 1900's mid terrace.
Currently bathroom is downstairs at rear of property (water and sewage are serviced at rear of property).
I am planning to convert the small back bedroom upstairs into a bathroom.

Boiler is a Potterton Ultra2 pressure heating gravity water, about 8 years old.
I will be moving HW cylinder into room above boiler (which is the room that will become the bathroom) and the CW header will go in the loft.

Currently the CW header is in the loft above the downsiaris bathroom (which is like a single extension with pitch roof - if i said coal shed/outhouse conversion you'd get the picture), and the HW cylinder is in a cupboard in the downstairs dining room.

I want to keep the current downstairs facilities (bog, shower handbaisin) as well as the upstairs bathroom installation, so the HW tank would service both bathrooms and kitchen.

Is there anything in particular I would need to consider before asking for quotes (other than buliding regs).

Many thanks!

Consider the weight of the cold storage tank when it's full of water, and whether the ceiling joists are up to the job of supporting it. Locating it over a load bearing wall, or adding bearers to spread the load can help. Likewise, the hot cylinder. The preferred position is often as close as possible to a wall that supports the floor joists.

Getting the storage tank into the loft in the first place can be a struggle - loft hatches are often smaller than water tanks. That's not a problem for the builders - they can stick the tank in the loft first, and build the roof over it!
Retro-fitting tanks may mean enlarging the loft hatch, or using interlinked multiple small tanks. Some tanks are made to fold up (if you have a black belt in origami!) to get through small hatchways.

Raising the cold storage tank as high as possible makes the most of the gravity pressure available.

If you are going to pump the outlets, now may be a good time to consider increasing the stored water capacity.

As said previously, where and you site the CW tank in the loft is pretty important, A solid base (no gaps) is required underneath the tank and must extend beyond the tank on all sides, also a good idea to remove any rockwool or lagging from beneath the tank to keep the chill off in winter time. If you need to increase your stored water, or can't fit a large tank through the hatch, linking smaller tanks together is a good option. Also make sure all the pipework and tank itself are well lagged, with these winters we have been having I doubt un-lagged copper tube in a loft space would pull through.
Again as previously said, the higher the tank is, the more head of pressure you will get from your hot water taps, though a 350mm clearance is required above the tank for access to service the ball valve.

Alex