Not sure where you are. Assuming you are building in the Southern Hemisphere then the first thing to do is move your garage to the south side of the block and let more rooms of the house enjoy the northerly sun in Winter. Make sure your corridor is wider than standard( imagine two people passing each other comfortably)- maybe an extra 30 cams- you won't regret this. A skylight here that opens to let hot air out in Summer is great. To further save cost, have all wet areas as close together as possible, and if possible,on the south side. A kitchen bench and whatever is on it can suffer enormously with the angles of the sun during the Winter months. Better to put this on the south side and have the family area bask in the warmth when it is cold. Large windows on the north side will ensure plenty of light through to the kitchen. Personally I love the idea of an internal access from the garage directly or as near as possible to the kitchen because I do not want to traipse through other rooms with heavy shopping bags or dirty shoes. Sliding doors to linen cupboards and bedroom wardrobes to save space. Back of house faces West so consider a wider eave to give some relief from the hot Summer sun, which could be shining into your family/dining areas till quite late each day.

These tradies are cowboys . I have never seen a mess like that in a bath or else where in over 30 years . The bath normally sits on a bed of concrete slurry or if it is a cast iron bath it should be supported by either feet or the hob. The bath should have enough room under the edges to allow the tiles to go under the lip so a proper silicon seal can be applied all the way around the lip of the bath. As for the insulation it is not necessary to have it wrapped in any water proof protection. If the water is getting onto the insulation then you have bigger problems and from the look of the photos this looks like a definite future possibility.I like to put insulation batts all the way around the bath to try to retain the water temperature for as long as possible,not many people do this though ,but the more you insulate things the better. Looking at your photos the pipework connecting the waste is broken off so the hob will need to have atleast one side pulled off or an access hole cut into it to connect the plumbing. I would be getting these plumbers and builders checked out,if the photos are any indication to go by then there would be other areas of faulty workmanship for sure, -sorry to tell you.

Hello oklouise I am sorry not to be able to respond more promptly I have been uber busy. Wow I love the plan for the bathroom - thank you!!! But I am really going to have to wait on my master suite and change a few things as I have spoken to a Renovator Friend who has made me aware my budget is a problem.. to the point I am giving the existing house AS IS to my in-law and just focusing on the extension for my family. :-/ for now? Always wanted a Master Suite!!!! The bedroom will have to be my office for now and I will out a door in what would be my future bathroom. (Insert crying emoji) Reno Friend has suggested get rid of wall separating mud room/ stairs area. She suggests flip entrance to stairs to closer to door (thereby giving opportunity for full windows over west entrance door allowing western sun. Full height wall where stairs end and slider door there to the middle living/dining wall she suggests we keep. Effectively divides the space into 1/3-2/3. I will need a kitchen in my laundry now as I can't access toilet in extension. Upstairs study will now be my bedroom - so area over void will become my wardrobe. Reno Friend vetoed the fireplace under stairs and said it has to be on western external wall. All these ideas she has a budget reason for implementing .. so. My Feng Shui lady will be despairing. I am quite deflated but the budget is what it is, it's going to be a few years to finish I guess. Thank you and instead I am sending a virtual feast of your inclination!!! Xx

Moving the niche is not an option at this point. But I do have a question about the niche. My tile installer wants me to consider using the gray tile (same as the floor) on the inside edges of the niche. This is because the wall tile is glass and imperfections in the glass (from cutting it) will show if the glass tile is on the inside edge. How do you guys think that would look? I tried to find photos of a niche where the wall and back of the niche were one color, with the sides being a second color and I couldn't find any examples. Has anyone seen that?