Hi Paul In apartments, the killer for layout changes are always drains, then water supply, then load bearing walls. Before you consider doing any changes to the layout, I would advise you to locate the drains (pics would be good) as they will likely restrict you. The drains are important for obvious reasons but also important is the fall (ie downward slope) of any drain you wish to install in a separate location. It means you have to take into account more height the further away from the existing drain you go. It is likely that your existing laundry trough/basin has a drain going down to the floor, and this is going to interfere with the proposed ensuite entry location. Ditto if it is going into the wall. The big one is the new shower. It will need to have a 50mm waste (drain) in the centre of where your washing machine now is.... and the question is where is it going to go.... I would suggest swapping the vanity and shower over to access the existing trough waste if it is large enough. In a lot of these older apartment buildings, the waste sizes are down at 38mm, which is not going to drain fast enough for a shower. If your existing waste is that size, you will need to have a hob to the shower as it will fill up, and you will also need to check health regs to see if it is allowed in your state. To get the drain for the new ensuite vanity and new laundrette sorted, I would punch through the new kitchen wall and run drainage along the wall behind the new cupboards and around to the existing kitchen sink waste. This will give you plenty of fall and a place to hide the pipes. For the new basin to the existing, you will need to see if you can get it around to the existing basin waste in the bathroom adjacent by running it around and under the bath. Cheers

Thank you both very much. You've both put a lot of thought and effort into this, its much appreciated! Its definitely opened up my thoughts and ideas on the space! Its definitely not as daunting as I was thinking and it is do-able! When you look at it everyday you get a bit stuck. I guess I need to weigh up making that study space smaller. It then makes the house technically 3B 2B. But I'm going to have to compromise somewhere for this to work! Its nice to have something tangible and clear to show the builders, so thank you! I might start drawing up something that's a little of both, as I love aspects of both designs. :)

reluctant to lose the convenience of outside access to a toilet my suggestion sacrifices a little space off the lounge and bedroom to keep the extra toilet and use the original laundry space for a bigger ensuite with separate toilet and double vanities, the new extension makes a more spacious wiw with only standard doorway openings to the new rooms but the ideal outside door for the laundry will depend on the location of the drying area and you may decide that a western door or no outside door (and walk through the verandah?) could both add more counter space to the laundry and, much as i like the gable roof for the extension, it would be interesting to obtain a comparative quote for a simple skillion roof (and raked ceilings for the new laundry and wiw) that may save a lot of extra roof structure that doesn't add anything to the inside of the new rooms or streetscape and could be much cheaper..

with the available space there's very limited options and likely that the existing ensuite already has a shower at one end and toilet at the other with sink in the middle..could you have storage pushed inside a wall cavity and/or is there any space available in any adjoining rooms?i