I would be curious in seeing if you have a good grasp on the numbers I posted originally and the effects they truly have on a home, along with a program you use that actually takes into account some of these things, such as thermal bridging and extremely low infiltration rates...cause ours does. Some of the hvac guys I talked to their programs maxed out at r29 insulation in the walls! Not to mention their "infiltration numbers were, well not numbers at all, but rater "loose, medium, and tight". (tight being 2 ach@50 pac, still way too loose). Its not a fight between who is smarter. Its a matter of new ways of doing things. Tried and true and gut feelings are all fine and dandy on typical code homes, but not here. It gets people out of their comfort zones and actually size things correct, heaven forbid. My HERS rater and ES rater came back with similar numbers now. I guess we are all crazy and the home will really, really suck. (just like the PH homes in VT, IL, MI, and other places that use a single point cooling such as a mini split with great results....)

Ok glad you found that useful. I decided to see if I could find some proof of the same ole shenanigans... yep sure did. Heavy on marketing and gimmicks low on realism and truth. But who needs truth? Now does this mean I am bashing Trane or Am. Standard? Only to the point in which they think their product is better than something else. The marketing gimmicks. They have to do that to charge more. If they told you 'hey our products are good, but you will pay more over the life of the equipment' would the you still buy it? But Ray, why wouldn't you just shut up and sell it anyway? This comment right here: 'Hey, you sold me this equipment --- you said it was the 'best', what do you mean the indoor coils are leaking freon? What do you mean the compressor is making noise that will eventually lead to it's death? This equipment is still new... if it was the best why am I having all these problems? That's why. --- no HVAC equipment is immune to failure. none. So sorry, Trane / American Standard is just as good --- or as bad as anything else. It will cost more to repair it. Marketing gimmicks cost money. -------- But what should I do then? Focus on design. Things like zoning / how it is going to be done. What is the better way for the project to be done? Sizing of the equipment. Don't over size even if you are buying 2 speed equipment. (A half ton over size is fine. Nearly 2 tons over size? uh---- NO.) Things like how much equipment versus controls --- further from that lay out. Ease of future service, the ability to easily repair the equipment, replace when that time comes. Things to reduce maintenance problems and or expenses. These things are fleeting when trying to get the 'cheapest price' outside of what the equipment costs. Because design is the skill level attained by 'experience'. With that said, new construction is often times none of these things. It's more along the line of sell the system(s), hire the sub contractor to do it --- and that sub contractor makes more money by completing as many jobs as they can. More often than not new construction has little to do with great design. Because of that I would zone the new construction home with 'equipment' as opposed to controls especially because you have the room to do so (5k sq ft) If you want zoning, add it later with someone who has in depth knowledge that it's even feasible. Experience is gained over years, decades in the HVAC field. As noted previously I do not do new construction. I come after the builder is long gone... in some cases as little as 1 year after the house was built. I service the Katy, Texas area.

Such a simple small house could probably get a load calc for $500 or so. Have you talked to an energy rater? Ours did a calc that the HVAC contractor used. Their fees were modest. I think it was $1000 for the overall package which included a Manual J, advice and inspection of insulation, submission for a utility rebate (we got $7500), Energy star certification which included blower door testing and duct leakage testing. Much of this is probably required with CA code - things like a blower door test and a duct leakage test. In my area, a manual J is required to be done but it is after permitting - it is required for HVAC inspection. Manual J is the typical load calculation. That determines how much tonnage you need. The complementary Manual D gives the duct sizes. (Just noticed that this is repetitive from above but different detail.) If you need an answer faster, you can download the software - last I heard available as a free trial for 7 days. Lots of inputs that you may not know. The biggest issue is solar orientation. Was that overhang designed to block the sun or more of a design element? One significant (and not often mentioned) advantage of a mini is how quiet the outdoor unit is. We have 2 trane XL15's and one mini. The mini is whisper quiet - like you feel the fan blowing on your leg rather than hear it to know that it is on. The indoor unit in our scenario is whisper quiet. Not to throw another option at you but ours is a ducted minisplit. With this the air handler is smaller than your average conventional system and also available at lower sizes.

The saga continues with our defective home…The builder is using legal threats, fees, and the long painful legal process to intimidate us. They are refusing to consider reasonable settlement offers or submit to mediation. Our lawyers tell us that a judge will, without a doubt, REQUIRE mediation before trial; yet our builder refuses to consider mediation without going through lengthy and expensive discovery and depositions. We are told this path will rack up legal fees over $100K this year without resolution. We could likely fix all the problems with our house for $100K, so the whole process seems ridiculous and unfair. Do we walk away and allow the builder to bully us and get away with shoddy, defective work? We just want to find some peace. We would walk away and sell the house, but we would need to disclose all the defects - sell at a significant loss - or subject ourselves to future legal action (if we didn’t disclose defects). We want to try and see if the developer, who provided us a list of ”approved builders” can help us mediate this situation outside of court, but our lawyer says we could get sued for trying to damage the builder’s business relationship. We want to file complaints on BBB, IBA, BAGI, State Attorney General, social media complaits…but our lawyer says the builder could sue us for slander… We find more defects and code violations every day…For example, we just confirmed the BROAN NuTone 636 roof cap (with a screen) used for our dryer exhaust is not approved for dryer venting… We don’t know what to do. This has been an unbelievable experience.