Given your location, I would think that the big issue would be, can you design to minimize the need for air conditioning? The choice of roof covering will have an effect on how much heat from the sun is absorbed by the structure of the house. You could put up a steel roof, painted white or silver color, and reflect most of the sunlight. A living roof, with growing grass, should keep the house cool, but will be more expensive to build and maintain. I would think that a green roof would require quite a bit of water to keep it healthy.

Given that geothermal will save you about 45% in energy costs over a high efficiency air source heat pump or air-conditioner AND provide free hot water, perhaps geothermal is NOT overkill. Calculating these savings at todayÂs energy costs may be quite revealing, much less energy costs extending 10 to 20 years out. The cost differential between geothermal and whatever else youÂre likely to install will be easily recovered when itÂs time to cash out and sell. Geothermal has the lowest operating and maintenance costs, longest life expectancy and highest user satisfaction rate of ANY space-conditioning system currently available, according to the EPA.

IMO

SR

Here is a link that might be useful: how-efficient-is-it-magazine.com

Thank you for the feedback. I am trying to get some real life, even if wildly underinflated for today, numbers to get a sense of how these efficiency/green measures fit into the overall budget given all the construction priorities.

I have been referred to, but by no means fully understand, some building science principles applicable to the hot/dry climate regarding things that are obvious to you folks like proper framing, ducting, sealing and insulation to improve the efficiency of any system. Those obviously are items I can't defer for when the purse strings loosen again. Likewise roofing is a longterm choice that must responsibly be made at the outset. So there will be those greater upfront costs.

If choices have to be made, are there ways to design now for a retrofit of geothermal at a later date? Solar energy generation? Thanks for any further thoughts.

We are definitely experiencing the east window heat now as the current house has large glass whole wall panels spanning 20 feet in one room, most of which don't even open, without any overhang outside, and that room is a cooker! I think it is compounded by the pool deck outside those windows releasing heat?

We just close off that room in the day at this point (we have no ac) but the way we are contemplating the new design, the major living spaces will be facing the east. Also, there will still be decking outside on the east and probably concrete floors so am I right to assume we will have the thermal mass concept working against us in the summer?

We are going to design for good cross-ventilation. There is a nice onshore breeze (West to east) during the day and offshore (east to west) at night (we are 4 miles in, but this is still how it works here). Those couple rooms in our house that have west and east windows stay relatively cool. Maybe we could fashion some kind of shading for the morning hours when the sun is coming straight in from the east, so we could block some sun but still be able to receive some breeze? Rolling planters with shading bushes or something? I will try to look on the efficientwindows website for the best glass for those applications, but the site just freezes on my computer.

We've never had a whole house fan but it sounds like a good idea, provided it works well with screens on the windows because I have an unreasonable hatred of mosquitos. Does a house fan affect sealing/insulation? (Given that we are in the 70s so much of the year, it seems I have just enough knowledge to be dangerous.)