Radiant Cooling? In the Ceiling?

July 30, 2010

Radiant mats installed on the second floor ceiling

One of the more novel approaches we using in the building is the process of heating and cooling the space with radiant mats in the ceiling.  The mats have a  more narrow diameter than the typical radiant tubing used in radiant floors (as seen below), but they work just the same.  In the floor, the tubing is encased in finished concrete.  

Radiant Tubing in floor


In the ceiling the tubing will be encased in plaster.  Both will create a ‘thermal mass’ and radiate heating and cooling up and down into the space.  The system works with a closed loop process, and hot water is pumped through the tubing in the winter and cold water is pumped through during the summer.  

Heating water (to run through the tubing) is more efficient than heating air, so the system will use less energy to provide the same amount of heat.  It will also be an even heat (making it more comfortable).   And because it is not a forced air system it will reduce the amount of contaminants and allergens blown around the space.  

Because the overall system is solar-based, the majority of heating will be free heat from the sun.  The set-up of the solar system is also novel in that it maximizes efficiency in a way that most solar systems do not.  The concept was initially implemented and shared with me by another green builder – Timothy Heppner. 

Below are two typical solar set-ups: 

two examples of typical solar set-ups

The downside of the above set-ups is inefficiency.  In the first example, the requirement is that the 100 gallon tank always maintain a certain temperature (ie 120 degrees).  So if the sun is not shining then either a gas or electric element heats the tank water- Even if there is no demand for hot water.   In the second example, there is no continual heating of the tank water (which helps efficiency), but if the tank water is not hot enough to supply heat to the forced air furnace, then the gas burner kicks on in the furnace and doesn’t use any of the solar heated water.  

In the system we’ve installed – the “Tim Heppner model”, the system is efficient because if there is no demand for hot water no fossil fuels are used.  If there is a demand, and solar production is sufficient then no fossil fuels are used either.  And finally, if there is demand and solar production is existent  but insufficient, fossil fuels are used only to make up the difference between what is needed and what the solar panels can produce. 

The Tim Heppner System

Wally Shah from Radiant Cooling Corporation

 Above, Wally Shah from Radiant Cooling explains the system. 

Robert Dec and Greg from DECO HVAC

the mat for the powder room is installed

More mats get laid out

Wally and Robert discuss some of the finer points (Wally isn't really mad)

Making Progress

Pressure tested and ready for water



Are those solar thermal panels on your roof, or are you just happy to see me?

July 14, 2010

6 solar thermal panels which appear to be on my neighbor's roof but aren't

John Caravette and Jerry Bradford from Earth Wind and Solar are finishing up the solar install this week.  The 6 solar THERMAL panels (not to be confused with the 40 solar PV modules on the Garage which produce electricity) will provide approximately 60% of all the heating needs of the home.  That includes domestic hot water for showers, faucets and such as well as the heating system which is a radiant floor and radiant ceiling system (and will be the subject of future posts).

Before the panels were installed though we Arthur with a little help from Superman installed the metal roof.  I found this nice description of why a metal roof on another green home’s blog – the equinox house.  In addition to the reason’s below, the standing metal roof has the bonus of not being made from petroleum. 

Why Metal?:

lasts longer (50 year warranty)
is lighter weight
higher wind resistance
fully recyclable
saves energy (keeps roof cooler)
sheds water and snow faster

Arthur and Ted check the line

Superman (aka Woytek) happy about the day's work ahead

Jerry from Earth Wind and Solar marks out the supports for the panels

Arthur's Progress

Mr Happy (photo looking east)

Arthur enjoying the heat

The finished roof

Jerry from Earth Wind and Solar, explains the system

Jeremy, the earliest investor in Elemental Building checks out the system

Jerry and Matt check out details of the supply line.

The view looking west

The 'Coyote', Bucktown's iconic tower building in the background

Two more happy workers (Matt-Left, Jerry-Right) at 1610

Are you Serious?

July 6, 2010

Windows from Serious Materials went in over the last couple of weeks.    Not only is Serious Materials doing the 6,500 window window replacement in the Empire State Building, but they are also doing the 35 window replacements in 1610 N Honore! 

Serious Materials builds one of, if not the most energy-efficient windows in the world.  The windows going in at 1610 contain 2 planes of glass, a suspended film, and krypton gas.  The frame is made from fiberglass which has lower thermal-bridging characteristics than vinyl, wood or aluminum and doesn’t have the carbon footprint of vinyl (an oil based product) or wood.    

R-value: an average window might have an R value of 1.  A really well-made double pane window from a company such as Marvin or Pella might achieve an R value of 3.  The Serious Materials Windows achieve an R value of 9.  The higher the R-value-the higher the resistance, the higher the resistance the higher insulation, the higher the insulation- the slower heat moves through the material, and the slower heat moves through- the lower the energy required to heat or cool the inside space. 

In addition to the recent press on the empire state building, the California-based company also made news a year and a half ago when they bought the Chicago based window company Republic Glass who gained national press when the workers staged a sit-in to save their paychecks and benefits when the then ownership up and left town and told the workers they were out of jobs.  Article.  So in addition to being good for the environment, it’s a company with a social conscience as well.

What’s with the balloon?   Since the windows are manufactured in Colorado at higher elevation, the change in pressure at Chicago’s near sea level elevation compresses the Krypton gas in-between the window panes.  Since the Krypton is an important part of the insulation, having less of it in the window is bad. . . . The solution?  fill the balloon in Colorado with Krypton and when the windows get to sea level and the pressure changes it forces the gas out of the balloon and into the window- and solving the problem.  The wire tube is then crimped and cut and tucked into the frame.

exhibit A


The truck arrives

two major sections await their new home

Chris, Woytek and Arthur take charge

a view from the south-east

A view from the West

Just the house

The master bedroom (middle level) and kitchen windows (above)

view from the south (Kitchen to the left, Stairwell to the right)



the Chapman family (Roy, Mel, Mitch, Dane, and Skyler) gets Serious