There are no hard and fast rules that must be obeyed when planning a bathroom - it's up to you! 

However, this is a good place to start:

• What do I like/dislike about my current bathroom?
• Who all uses the bathroom?
• What are their needs?
• Is there enough storage?
• How many people have a bath?
• Does my bathroom need a bath or could space be increased by having just a shower enclosure? 

It is worth discussing with a plumber the practicalities of moving pipe work and e.g. if your water pressure will need an extra boost for a power shower - it might work out more cost effective than you think! 

Other considerations

• Stick with white or neutral shades for your suite, they don't date!
• Consider extra lighting for your grooming areas. NB Water and electricty don't mix. All electrical work should be completed by an electrician
• Create extra storage with fitted bathroom furniture
• Heated towel rails provide warmth and towel storage
• Mirrors create the illusion of space especially with strategically placed lighting
• Consider improving your ventilation

Designing a bathroom for people with special needs

There are various products available to ensure ease of use for those with special needs. Whilst in general very safe, bathrooms can present many hazards that can be addressed by choosing the right equipment and appropriate design. 

• Is it accessible?
• Can the door width and opening accommodate a wheelchair?
• Is it private & secure?
• Is there enough space?
• Is there enough room for the bather, carer and wheelchair?
• Would support or grab rails be of benefit?
• Is the suite easy to use?
• Would a low sided or easy access bath be appropriate?
• Would a fold down shower seat help?
• Is a large height adjustable basin required with lever-operated taps?
• Would a raised WC be better?