Neal Creek Farm
Franklin County, Tennessee


Zero Energy Off Grid Home
Super Insulated Steel SIP House in Tennessee

April 1, 2011 happened to be April's Fool day and was also the day that we decided to embark on a new super energy efficient zero energy input off grid home construction project at Neal Creek Farm.  This and other pages in the website will be the place where you can follow our exciting journey.

The idea of a totally energy self-sufficient home started many years ago.  I have done some environmental writing in the past.  A couple of writings from 10 years ago that might be of interest:

Sunshine Cottage was our initial project for learning to live with less energy and with energy generated by sunshine and wind using solar panels and a small wind turbine.  See learning to live off the grid.  Sunshine Cottage is moving to a permanent foundation in a few weeks and will be a guest cottage where you can come for a weekend or a week and learn for yourself what off grid living is all about.

The photo is a 180 degree panorama of the west bank of Neal Creek taken from the spot on the hill where the water well was drilled April 22.

The House Plan

Designing a house can be a great way to upset a marriage and we have taken our lumps on several previous attempts, but this time things came together surprisingly well.  The house is designed the way we live and also anticipates that both of our mothers are alive and may end up living with us at some point in the future, or, depending on the state of the world, 4 kiddos and 8 grands may be residents.

Form is related to function, a simple 40 wide by 32 feet deep gable roof with a 12/12 pitch that allows upstairs room in the gable for an extra bedroom and a bunk room, game room, bonus room etc.  The house faces due south toward Neal Road.  We do not plan to put solar PV on the roof, but there may be some thermal solar collectors.  Facing due south is important to the full length of the house porch, which will be enclosed with 13 large single hung windows to be a greenhouse and thermal gain envelope during the winter.

The porch on the right (east) end of the house overlooks Neal Creek.

The porch will be all under roof with a slab on grade for wood storage and access to the walk out basement.

The north side includes a mudroom entrance which will double as pantry storage for the kitchen.

The west end entrance to the greenhouse porch will be on grade with a small ramp for wheel chair access.

The main floor entrance offers the option of heading up the stairs or into the main room of the house which will have French doors that open out to make the living, dining, kitchen, deck and front porch all one space during suitable weather.  Part of the design idea is to minimize waste space in halls which is always a challenge for small houses.  In the center of the house just above the long run of the stairs in this view is a wood stove which will also be suitable for cooking if needed.  The master bedroom and bath are top left, guest room lower left which adjoins a fully accessible ADA compatible bath.

The space in the gable with three small dormers provides a surprising amount of both living and storage space without having additional wall exposure or expense.  A third full bath is in the future plans if needed along with a large bedroom to the left.

The roof plan shows flat rather than peaked gables which are easier to build and easier to roof, no valleys on this roof.

The basement will be exactly that.  Not shown are plans for a storm room top left which will be below grade.  All the solar electric hardware and battery bank will be on the wall just to the left of the stairway.  The rest of the basement is for food and necessities storage and the garage door is to provide access to get our 27 hp tractor into the warm and dry for winter maintenance.  The floor beneath the front porch will be earth and the void in the porch will be the heat sink for air tubes which will circulate air from solar powered fans during the day for heat gain with radiant or solar powered fans during the night to bring warm air when available into the living space.  Air tubes will be bedded in coarse gravel for heat sink.

Thanks to Bruce and Cyndy Gardner of, long time friends and clients for drawing up the plans.

The House Construction Materials

After looking at all the options, structural insulated panels or SIPs made from recycled steel and insulated with soy-castor foam insulation is the choice.  Stick or balloon framing was never a consideration considering the increasing intensity of storms thanks to climate change.  We looked at conventional SIPs, and insulated concrete forms and everything else.

The steel home kit is our choice.  The walls, floor systems and roof is all panelized with windows and insulation pre-installed.  The walls will be R30 plus and the roof R50 plus.  The main floor panels do down first, bolted to a 12 inch concrete block foundation with every block steel tied to the footers, concrete filled and steel reinforced.  There is a bolted and screwed structural connection from the top of the foundation walls to the peak of the roof.  Porch roofs will also be steel panels.

I think steel house building is going to be increasingly popular for several reasons: strength of construction, high insulation efficiency, rapid assembly on site and low cost of ownership.  We will tell more about this as the project moves forward.

Check out our website where we are offering practical renewable energy solutions just like the ones you will see here.

The Site Excavation

Super energy efficient home site excavation photos.

The Foundations

Work starts June 20.  Sunshine Cottage goes first so we can move it out of the way for the main house.  See the foundation photos here.

Drain tiles are essential and more so on a hilly site like ours.  See the drain tile installation.

The concrete block walls are steel reinforced and concrete filled.  See the process.

A Hot Idea? We'll find out.

Fame or folly, we buried 200 feet of 6 inch PVC under about 25 tons of limestone rock in the porch portion of the basement.  See the earth tube photos.  A detailed explanation will follow including a sketch of the layout.  I gave my camera to one of the crew but he forgot to take the photos.

The Pump House

Every good pump deserves a home, especially if it is a solar powered Simple Pump.  See some photos.