Tuesday, August 14, 2007

Cheap information - 8th Annual Renewable Energy Roundup in Fredericksburg, TX (1.5 hours west of Austin)

If you find yourself in the Texas area end of September or are lucky enough to already live here :-), make sure you come to the 8th Annual Renewable Energy Roundup at http://theroundup.org/ in Fredericksburg, TX September 28th-30th in the center of Texas Hill Country.

It's $10/Friday, $12/Saturday or $20 for all three days! That's a bargain for the amount of information you can get on these hot topics:
  • Solar
  • Wind
  • Geothermal
  • Water Use & Reuse
  • Energy Conservation
  • Rainwater Harvesting
  • Green & Sustainable Building
  • Organic Growing
  • Alternative Transportation
  • Straw Bale Construction
And there will be:
  • Exhibits
  • Free Guest Speakers
  • Natural Food
  • Family Activities
Come and learn something new or meet contacts in the green field. Besides, it will be a fun trip and nice drive over there, as you'll pass some beautiful areas, and the historic town of Fredericksburg with its German influence and charming old west appeal.

Our architect and I might exhibit there and advertise our blog and my upcoming e-book. Let us know if you live in the Austin area and want to carpool! Thanks to Maverick for passing this information along!

Thursday, August 9, 2007

About SIP walls and a residential flat roof, logic behind these alternative building methods

As our design is coming together under our structural engineer, Green Earth Engineering, I thought I should explain how and why we chose SIP walls and a residential "flat" roof design. They are
mostly because of cost-effective and energy efficient reasons, and I'll explain why in layman's terms.

First, SIPs are a composite building material. They consist of a sandwich of two layers of structural board with an insulating layer of foam in between. The board is usually Oriented Strand Board (OSB) and the foam either expanded polystyrene foam(EPS), extruded polystyrene foam (XPS) or polyurethane foam .

They are not commonly used in the building industry due to knowledge or resistance to trying new methods, which is very unfortunate, because they are superior to conventional stick framing and pay themselves back in cost due to energy savings.

So here's a breakdown of why we chose SIPs pulled from my architect's website:

Benefits for homeowners
* Extremely strong structure. There is considerable evidence that homes with SIP wall and ceiling panels have survived natural disasters like hurricanes, tornadoes, straight-line winds and earthquakes better than traditional stick-framed homes right next door.
* Lower energy bills. Discounting the "human factor"-thermostat settings and so forth-a number of side-by-side tests show that between 15% and 40% less energy should be needed to heat and cool a home with SIP wall and ceiling panels. In tests by Oak Ridge National Laboratory, SIP walls outperform fiberglass walls by over 50%.
* Improved comfort. Thanks to extra R-values and tight construction, the wall and ceiling surfaces in a SIP home will stay warmer than in stick-framed homes. The warmer those surfaces are, the more comfortable the home is.
* "Freeze proof." What happens if the power goes down? During the late 1990s, several New England SIP homes survived over a week without power or a wood stove and never came close to freezing.
* Indoor Air Quality. While there is no guarantee here, most homes built with SIPs are tight enough that builders can't ignore upgrading mechanical ventilation compared to that found in a standard home. In many studies in North American housing, the best indoor air quality is found in homes that are tight and equipped with upgraded mechanical ventilation.
* Green building product. On a life-cycle basis, a more energy-efficient house built with SIPs will be less damaging to the environment, in terms of overall resource consumption. Much less dimensional lumber is used in a SIP home than in a traditional framed structure.
* Interactive systems benefits: For example, a more energy-efficient home may cost slightly more to build but in turn can be heated and cooled with smaller equipment that costs less to install.

Benefits for construction
* Speed of construction. You can order the panels with all pre-cutting performed in a factory. They show up on the jobsite all pre-numbered, ready for assembly.
* Fewer framers. A crew can consist of one lead framer assisted by minimally skilled helpers.
* Shell installation option. If you're having a tough time locating skilled carpenters, a growing number of manufacturers have regular crews who will install a shell on your foundation for you to finish.
* Rigid frame. It's easy bracing SIP walls. In fact, once you have two corner panels up, you can lean a ladder against the panels when needed.
* Less jobsite waste. If you've ordered a set of panels with all rough openings for windows and doors pre-cut at the factory, the only true waste you'll have is taking a few cases of empty tubes of adhesive caulk containers to the dump.
* Less theft. While 2x4s and 2x6s are prone to "walking off" unsecured job sites, panels are too specific to the site's building system to be worth hauling off somewhere else.
* Cost competitive. While most builders say they pay a little more for SIPs than for the comparable framing and insulation package in a stick-built home, as a group they believe the benefits are worth the costs. The amount extra they pay varies; while a few say it costs them an extra $1 per square foot of finished floor area, the amount may be higher when roof panels are used. However, when roof panels enclose extra living space in a loft, the price per square foot is surprisingly competitive. If at the design stage you optimize a structure to use panels, the most experienced SIP builders then say a house framed with SIPs should cost about the same as a house framed with comparably sized dimensional lumber, and maybe even a little less.
* Easier to hang drywall. There is solid backing for all drywall against exterior walls, which means there is less cutting, faster attachment and less waste material.
* Fewer framing callbacks. Wall panels go in plumb, square and straight. Once in place, a SIP won't warp, twist or check.

As for our "flat" roof design, our architect advised us that a good way to SAVE MONEY is to get a commercial grade "flat" roof because you don't have to pay for those beautiful Spanish ceramic tiles found on Spanish/Mediterranean style homes, which can get extremely expensive. Besides that, the flat roof goes wonderfully along with our design aesthetic, it being modern and clean-lined. Now, many modern homes use metal roofs with overhangs, which are equally as nice, but we chose this design for cost reasons, having to be "cheap" but not compromise a good quality structure.

The way our roof will be designed is it will first be a SIP panel, then styrofoam wedges to give the roof a 1 to 12 pitch for rainwater drainage, then a thin membrane lining. There will be a parapet wall (wall that goes higher than the roof line) as shown below:

The reasoning behind the parapet wall is to both protect and "cover" all that is ugly on top of the roof. We will also prepare our roof to be solar panel ready.

As you can see in this design, we will not have a truss or attic space under the ceiling as the interior will soar all the way up to the SIP panel, creating a spacious looking living room with extremely high ceilings! High ceilings make any room look bigger, which is the effect we are after. The duct work from our HVAC will be in the floor of the 2nd story, thereby not needing an attic or truss at the ceiling.

Monday, August 6, 2007

Learned something new - solar water heating

Yesterday, we met with Maverick, a guy who builds solar powered "everything" and does it as a hobby! He even has a solar powered lawn mower, and we couldn't help but ask what his house must look like :-). Anyway, we were at the Alternative Energy Meetup, and though it was just us three, it was a greet meeting with lots of free information. The guy is an engineer who likes to build solar power projects, and the topic for the day was solar water heating.

There are several systems for heating your water, some really cheap and/or simple, and some can be elaborate, but a very doable DIY project if you know how to put together pipes.

1. Batch system, where sun heats water directly on the tank. The tank can be painted black to absorb heat and can be used alone or with an On-Demand water heater. Con is that it can freeze over because it is exposed to the elements. Typically used in the tropics, where the only likelihood is when hell freezes over! :-P

2. Thermosyphon, similar to the batch system, except in structure, where heated warm water travels up the tubes and to the top of the tank and cool water enters at the bottom of collector. Batch and thermosyphon systems are both non-automized systems, they work with physics, saving electricity, obviously!

3. Open loop direct, preheats water as it is consumed and controlled with a snap switch or digital controller in your house. A small pump (usually PV powered) circulates the hot water.

4. Glycol system, designed to be freeze resistant, where the collector fluid is a glycol/water mix and the heat exchanger transfers the heat from the collector loop to the consumption loop. It is within your home

5. Drainback system, similar in construction to the glycol system, but the collector fluid can be just plain water and requires the least maintenance. Water does not come in contact with freezing temperatures. The advantage is fewer parts and no chemicals!

A system with new parts and installation can cost about $3,500-4,000, or you can buy used parts & PV panels (solar panels) from e-bay, craigslist or through Maverick Solar and install it yourself for about $1,000 if you're a good DIY person.

Anyway, Maverick was very informative and gave us some great resource material. He says if you are considering solar panels, you must visit these places:

www.homepower.com (a must for solar power users, he recommends you subscribe to the mag and download the free PDFs)

Alas, here's some free PR for him (although this is his hobby, he probably will consult):
Maverick Solar (http://www.mavericksolar.com)

If you contact him, please tell him where you heard about it!

Wednesday, August 1, 2007

Thought you couldn't afford solar panels?

Now there's an affordable and totally attainable solution! I was so happy to find that there is a way to have solar panels without spending the $25,000-30,000 for a 3 kW system. Unfortunately, we don't live in the Austin Energy service area, so we don't get to take advantage of their generous rebates AE members get (something like 75% of the costs!).

Basically, a company called CitizenRE, would rent you the solar panels and you buy the energy produced from those solar panels at about the same cost or much cheaper than what your electric company charges at a 25 year locked in rate if you sign the 25 year contract! CitizenRE would handle the installation and maintenance, and you only need to put in a deposit, but at least there's no big system purchase to worry about and the contract is transferrable if you sell your house. More details can be found on the CitizenRE site, and there's even a nifty solar calculator:

I like the part about how many trees you save, your carbon print on the planet and how many autos you take off the street.

I found Christian Soeffker's profile, an Independent Ecopreneur of CitizenRE, on an Austin Meetup board. He filled me in on how this is done, so if you contact him, please tell him where you heard about it!