Oh Lorraine, this build has been a journey for you. Disappointingly your building designer didn’t highlight this limitation earlier because it’s well known that raked ceilings and rooflines don’t lend themselves to ducted air con unless the roofing gap is specified quite early in the design and allowed for in building costs. I’m assuming you’re also on slab and can’t go through the floor (it’s not ideal but you can duct cooling through the floor). I don’t have knowledge on bulkheads but if I was trying to resolve your issue I’d be looking for a HVAC consultant who are often mechanical engineers with experience in building. On a practical note you could consider multiple head split systems in the non public areas (although I agree with you on the looks) and is it possible to drop the ceiling to have space for ducting to run (you’d still need a location somewhere for the unit).

Houzz members suggested an alternate plan but I thought we were too far down the track and had invested too much to switch. I now wish I had!

You could look at exposed ducting, which can be natural metal or painted and can look excellent

https://www.houzz.com/magazine/hvac-exposed-20-ideas-for-daring-ductwork-stsetivw-vs~7371030

Interesting concept. I suspect hubby would be very hard to convince, but maybe it's worth a try. Apparently the main unit is the biggest issue, but I can't see why it can't go in a dropped ceiling in the store room - or even exposed for heaven sake? It's a store room - a cupboard that hardly anyone but me will enter. What does it matter what's in there?

From what I can see the main problem with the store room is that it isn’t centrally located which means the other end of the house is a long way from the bits that generate cool. Can you have the main unit in the storeroom to service all but the far bedroom/study wing? And then a multi head for that end of the house? I suspect you may need to allow for a bigger unit and more ducting for the main unit but worth asking.

Funny thing just happened. While I was writing, a gentleman turned up completely unannounced and said "I heard you were looking for air con solutions. I run an air con business. Can I take a look?" Took him two minutes to then say "Why can't you have ducted? Just put two small units in instead of one large. One each end of the house. I won't promise, but I'm 99% certain I can get them in with no truss modifications at all. I've done more challenging jobs than this."

Up to now, all I've heard is 'can't be done - you'll have to have splits''. So nice to talk to a problem solver! He actually said I was lucky the first company I dealt with bailed, because the unit they were selling me was too small anyway.

You might find that the main unit would be too noisy for the Store room. Our main unit was installed on the exterior wall in our previous house. Our current neighbour has theirs on the exterior wall opposite of or dinning area and is very noisey. Brother inlaw has his installed under a small exterior verandah away from living and being on acres no noise to worry anyone

What a great find Lorraine and a good solution. You must be relieved. I had a suspicion you’d need two sets of equipment but so good you found a professional.

Funny who you find when you've given up and stopped looking!

Well done, another box ticked

Yes. Now if we can just get a darn roof on, we might be able to get it finished by mid next year. It's only taken 14 months to get to frame stage!!! Roof was to go on two weeks ago but the builder didn't order scaffold and there's an 8-14 week wait for it, PLUS 3 weeks shut down over Xmas.

Just a thought, what would it cost to buy your own scaffolding, if it's available, then sell when you have finished as there appears to quiet a demand for it

Need a licensed scaffolder to erect it, and they will only work for the big scaffolding suppliers apparently. Maybe worth looking into further though.

https://globalscaffold.com.au/product/roof-barrier-edge-protection/

Oh, I'm so sorry to hear that siriuskey. I'm glad he survived.

He's my husbands Identical twin which made it harder, but he's a fighter, thank you.

Another Scaffolding company.

https://australianscaffolds.com.au/scaffolding-for-sale/edge-protection/

Do you need air-conditioning? The design looks as though it has been designed as a passive house. Depending on where you live do you need heating on cooling? Where are the prevailing breezes? Sun orientation in every season?

HU-549858008 - it is a passive design with excellent insulation, but the humidity here is murder and I feel the cold terribly in winter. The house does get the prevailing breezes, especially through the kitchen/dining and main bedroom. And winter sun in all the living areas and study. Plus ceiling fans in every room. But I still feel air con will be a big benefit, even if it isn't used much.

Fascinating how experts differ in their opinions. Today we had a man with a real can-do attitude look at the house and declare that definitely it's possible to install ducted with only ONE unit, though it would be much more efficient to have a split in the main bedroom to reduce ducting requirements. I am very happy with that solution. Now why has it taken calls to no less than 8 companies to get that answer?

Two units was okay until we saw the price! One unit and a single split sounds far more practical. And I agree that it will be far more economical to run because we'll turn the main system off when the bedroom unit goes on except on rare occasions when we have guests staying over in very hot or cold weather.

Bulkhead units could be worth considering for your rooms with external and internal walls. They provide a discreet installation option and can be connected to an outdoor unit through a duct directly through the wall. In the bedrooms, utilizing the space above the wardrobes for a bulkhead unit sounds like a clever idea, with the duct running from the unit to an outside unit.

As for the lack of innovation in making air conditioning units more attractive, it's a valid concern. However, some brands like LG Art Cool and Mitsubishi offer colored units that might be more visually appealing.

If you're looking for suggestions and information, check out a/c repair in Riverview, FL. They can provide expert advice and guidance tailored to your needs.

After about 12 different air con companies gave conflicting advice and left me hopelessly confused, a 13th company came and looked and the installer said '"I don't see the problem. Right there I can get a central unit (pointing to above the corner of the living room). I would suggest you consider maybe putting a separate split system in the main bedroom, just because of the load on the central unit to distribute over that distance. It's your choice, I can hook it to the central unit if you wish. I just think for efficiency maybe a split in that room would work better.""

I took his advice. Got a great price. Very good service. Central unit seems to work just fine. The split in the main bedroom also works perfectly. There is a unit above the ensuite opening which doesn't look too offensive and the outdoor unit for it is at the back of the house, well out of the way. It offers the advantage that when the two of us are alone in the house (which is most of the time) we can warm or cool the main bedroom and leave the central unit off at night.

The central outdoor unit is behind the garage, so well out of the way and not visible to anyone except whomever is hanging washing on the line beside it or taking out garbage.

Astonishing that it took so long to find a real expert, but there it is. We are now living in the house and despite some defects that can't be fixed, we are loving it.