For the roof, a steel SIP could work, but it's a pricey proposition, and probably not the best solution. Concrete or tile roofs would have some thermal mass benefits to pull the roof gains down. You'll definitely want to insulate the roof to at least R40 continuous insulation if you go low-mass, which is a pretty pricey steel SIP.

IRC code-min is U0.030 (= R33 whole-assembly-R, with all thermal bridging accounted for), but you can probably do just fine with continuous R25 foam sandwiched in a SCIP. If there are local swimming pool companies with idle time on their shot-crete equipment it may make sense to do the whole house as a SCIP monocoque, with a R15-R20 SCIP walls and an R25-R30 SCIP roof.

Huh. I wasn't even aware that ICF/SCIP could be used for the roof as well. That is definitely something I can consider asking the builder and talking to the designer about (when I manage to find one willing to work with an existing floor plan). Okay, so steel SIP is out. I am just going to have to tell him that I am not interested, as I am on a budget.

As far as buying from Mexico or China, heck yeah I'll do it if it is something that I can get away with, and as long as it is quality material.

I finally found an Architect who is willing to look at my floor plan and 'consider' working with me and my budget, so that is a great step in the right direction. I will keep you apprised.

My impressions of Architects so far is that they are people who are only interested in how much money they can make, and are unwilling to work with existing customer's plans and ideas (only want to do things their own way). It really is like pulling teeth trying to find someone who is willing to work with you. But, alas. I NEED one as my builder can't continue without proper blueprints.

I beg to differ that price would rule out a steel SIP roof. If they are incorporated into to the design early enough then they can eliminate several other steps and building components.

You don't need an architect to get plans. A plain 'ol draftsman will do. Every structural engineer will have one, or contacts with one. Draftsmen in my experience take the opposite tack, insisting that you know exactly what you want. They don't want to get caught up in the benefits of full john on the first floor vs half john. That said, a good one will tell you that your bedroom windows don't meet code, that your stairs are too steep, or that a door must sweep over a landing of x dimension.

Also, there should be plenty of free advice in tree-hugging Austin about good energy design, starting with your friendly local utility. If it is Austin Energy, start by calling its solar help line at 512-482-5346 to ask for local resources. Call them even if your utility is not Austin Energy. If any utility can be described as lovable, Austin Energy is a leading candidate.

There will be a single room-sized basement to be used as a utility area, the size of this is to be determined, but approx 11x12 ft.

My guess is that such a small basement will cost more ($/sq ft) than above ground space. At least ask about a frost protected shallow foundation (ie, no basement).

jonr: Yes I was wondering about that. I kinda need the basement since it would be able to better regulate the temperature for the batteries and other electronic devices I am going to use. Maybe I will get lucky and find someone to dig the hole cheap.

todm: I actually spoke with a structural engineer, as a matter of fact. They were one of the few individuals that were willing to speak with me, and even had a brief conference call with me when they had a look at my proposed floor plan. They said that they would definitely help me out, BUT they would need to know measurements for everything, Like, the size of the rooms, height of the walls, how steep the roof is going to be, height of the doors, shape of the windows, size of the windows. All that stuff which I know almost nothing about. I don't know the prices of different shapes and sizes of windows, I know what I want, I know the total square footage that will fit my budget, I know what I want my kitchen to have, but I am not an expert. They wanted me to fill in this information and to call them back, which is not going to happen, as I need someone with the experience to tell ME what is and is not going to work, based on the drawings (with no size information) that I provide. This is a very hectic time for me. Not being able to find the right person to do the job, quite frankly, stinks.

Jelly: Well I don't know the real costs of steel SIPS (and I don't know if this particular manufacturer even offers them, as he mentioned that his stuff contains wood) so, I suppose I can ask.

The old saw: You can build it fast. You can build it cheap. You can build it well. Pick two of the three.

I spent two years planning this house and drawing it up on then-Google Sketchup -- the kitchen got to something like ver. 14.3 --and I still wound up with a few gee-I-wish-I-hads. There is less margin for error in green homes because 9 of 10 buyers at resale have no idea what SIPs or ICFs are. Dream home 2.0 is harder if you leave money behind in the first. I dare say there is no margin for error in an off-grid house with a utility pole out front.

So I have some good news! I have found a designer that provides the exact services that I am looking for. He is a designer, not an architect. He is the one that draws up all the building specs using the CAD software and whatnot. He is willing to work with me and my project! He even gave me an entry quote as far as the costs associated with such a markup (which is approx 4-5% of the cost of the home), so it's going to be around 4-5K for all the technical plans, which is reasonable to me. I've already emailed him the few drawings that I have done. It also just so happens that he knows my builder and have worked with him in the past, so that is a double win as far as I am concerned.

toddm, I thought about resale too, but this is a home that I will be 'settling down' in, i.e. permanent residence (unless I win the lottery), so that is less of a concern with me. I would rather have something built to where I am happy with the design and result, so I won't be miserable.

A final caution. Texas is a caveat emptor kind of place where occasionally a homebuyer gets to pay subcontractors the same money he already paid to the builder, or pay twice in other words. Three ways to avoid mechanics liens by subs: require waivers from subs as they complete work. Hold the final payment to the builder, aka "retainage," until the deadline has past for subs to notify you that they haven't been paid. No. 3, find a respected builder who has been around forever and isn't dreaming about running off to Mexico with his secretary. My knowledge is dated so doublecheck the above with your lender. Introduce the subject gently with your builder. Few Texans recognize the peril, so he'll probably be taken aback.

I second toddm's concern...be very careful. People also tend to spend a fortune working with architects or other "plan makers" and are not always happy about what they ultimately received for the cost. You can likely purchase Chief Architect software for way less and build beautiful architectural plans easily yourself if you are so inclined. Building your own plans enables making many changes and looking at the renderings before calling it final. Anyhow, just a thought...

Posted By Sabotender on 03 Mar 2016 09:53 AM
...Well I don't know the real costs of steel SIPS (and I don't know if this particular manufacturer even offers them, as he mentioned that his stuff contains wood) so, I suppose I can ask.

Ok well the wood guys aren't going to offer steel SIPs, but they are in use in Texas. Also there is a build/design team in Dripping Springs who have done some projects with them.

toddm, sailaway: I had no idea that something like that can happen! I will specifically request these waivers to make sure no one can put a mechanic's lien on my house. I know my plumber subcontractor personally, so I know he is trustworthy....but now that you've successfully put the fear in my heart, I may as well request a waiver from him as well.

Jelly: That's what I thought, but it is just one other thing I get to talk with my designer about.

The designer said that Mini Splits cost more than traditional HVAC systems, is this correct? Even if they do, would the costs even out since it is very easy to install them compared to putting in HVAC ductwork and having a big blower? I really like the idea of having a ductless home. Fewer components that I have to worry about in the future.

you should need, at most, two minispits for your 1700 SF house, which in our area would cost around $6-$7,000. That's heating and cooling; very quiet, very even temps.

Bob I: Subtract 700sq ft from that. I've reduced the size and design of my home, turning it from 'modest' to 'very modest'. Seems efficiency doesn't work well for large homes, and too many people were losing their shirts over me wanting to be off grid on a 1.7 sq ft home. So, i've reduced it to 1000 sq ft. It's only me living in it after all. What do I care about losing some unnecessary space? As long as I get a full kitchen and 9-10ft ceilings, I'm golden.

About the HVAC, I'm more concerned about energy efficiency than how much sound it makes. I'd deal with something that sounds like a jet engine if it ran on 10W, high BTU, full power. I think mini splits are more efficient than a traditional HVAC unit.

so in answer to your cost question, you're looking at one mini split for probably somewhere in the $3,000-$4,000 range.

If it is still 2 story, you will probably want 1 small mini-split for each floor.

I kinda need the basement since it would be able to better regulate the temperature for the batteries and other electronic devices I am going to use.

Not sure how well this will work. You can insulate the basement ceiling and not insulate the basement walls/floor (to maximize ground coupling and summer cooling). But wet lead acid batteries need venting, and this could move a lot of heat into the basement (or to the batteries). If it does provide net cooling (after accounting for venting + heat from the batteries and electronics), it will create high humidity and probably mold. Maybe OK if you use a small ERV. Like AC, dehumidification is a power hog.

With modern alternatives, building underground has been generally debunked as a cost effective/practical energy saving design. Consider creating a buried battery box separate from the house.

Bob I: does that include the installation as well? That 4-5K is for everything? If so, that seems reasonable to me, but I'll still find the best A/C installer at the best price, and I'll purchase the units myself if I have to, instead of doing a package deal. What does that compare in cost to conventional HVAC install, including the ductwork?

arkie6: still a 2 storey, but it is a loft now. Bedroom has balcony that overlooks the living area. I mean, I don't mind getting a 2 zone system, since the cost is not much more compared to a 1 zone, but there's no longer a wall that separates the bedroom from the rest of the home. It's all open now.

jonr: Oh I've already thought about that, the lead acid batteries need to be vented anyway, so they will be placed in a battery box which has an outside vent. I don't think humidity would become an issue. The temperature underground generally remains a constant cool temperature throughout the year, which is why I wanted to do it this way. I can always place an automatic dehumidifier with an automatic pump if it is a serious concern. Even the good ones are portable and inexpensive.

yes; that was all materials installed with compressor. I would not self- install these, but some people have done that.

Bob I: Ah well that is not too bad then at all. I wouldn't dare install something like that myself, for it would void the warranty and might not pass city inspection.