Efficient home heating, Part 1.

Nighttime lows have been dipping into the twenties, making my cozy little home all the more comfortable.  The Armstrong House, the physical structure that protects me from the raw forces of nature, envelopes me in a bubble of evenly warmed air.  The source of this warmth: underfloor – or radiant – heating. Although winter is a great excuse to wear indoor slippers, they are not much needed as my floors radiate a steady stream of thermal energy.  On those early mornings when my cat's demands for breakfast rip me from the bed, my toes happily waltz naked across the heated floor.

Walking on heated floors is a delight in the Armstrong House

A little background on the Armstrong House 
When the Pound Ridge Land Conservancy (PRLC) committed to renovating the Armstrong House, they decided to use it as a showcase for simple energy efficient building and lifestyle choices.  The PRLC chose to prioritize energy efficiency because it realized that both prongs of conservation (land protection and sustainable lifestyles) need to be practiced and taught.  At the Armstrong Education Center we call this philosophy 'Living Lighter on the Land', and radiant heating is just one of the many ways we demonstrate a low-impact lifestyle.   

How radiant heating warms the Armstrong House
Like the tortoise, radiant heating (AKA, underfloor heating) is slow and steady.  There are many different radiant systems available – air, electric and water – which differ in their heat-carrying medium.  At the Armstrong House we use water (AKA, 'hydronic') to carry heat throughout the house.  Here is how our system works: roughly 90 degree water is continually pumped throughout the house in underfloor plastic 'PEX' tubes.  The water's heat energy leaves the tubes and radiates upward into the cooler room. Radiant heating systems can be thermostatically controlled, just like other home heating systems.  Take a look at the pictures below to understand the basic design of this heating system.

Underfloor tubing runs throughout the entire Armstrong House like in this picture.  

A picture of plastic 'PEX' tubing in a room.  This tubing will be covered by a floor.  

A detailed look at how radiant tubing sits under a floor.  

Radiant heating versus other types of heating
What makes radiant heating so efficient and great feeling is its omnipresence – the tubing underlies nearly all of a room's floor, which means that heat enters the room from almost every inch of ground.  Alternatively, radiators and forced-air systems rely on a few sources of very hot air, which is expected to permeate a space.  The result with these systems are drafts, hot pockets, cool pockets and – as you'll see – a room that is heated from the top down.

Two systems of heating compared.  Forced-air systems on the left and radiant floor systems on the right.  In most cases, radiant heating is more efficient and comfortable.  

Radiant heating literally heats a room from the bottom up, which means that the space occupied by people (the bottom six feet of the room) is the warmest and most comfortable.  Alternatively, by heating a room in a top-down manner (as in a forced air system), energy is wasted heating unused air.  This also creates very dramatic and noticeable differences in heat conditions between floors.  For example, I remember in my grandmother's house the second floor was brutally hot while the first floor was comfortable.  Besides being uncomfortable, this style of heating is inefficient.    

Comparing how heat fills a room in different heating systems.  Radiant heating on the left vs. force-air heating on the right.  

The body's response to different heating systems
It is said that radiant heating has advantages over other heating systems on a purely physiological level.  When looking at the heating preferences of the human body, our feet and legs like to be the warmest and our heads like to be the coolest.  The diagram below reiterates the point that a bottom up heating system has advantages over a top down heating system.

Our bodies like to be heated from the bottom up.  Our heads like to experience slightly cooler temperatures than our legs and feet.  

When trying to reduce your energy and resource use, you have to tackle the large energy hogs, like home heating.  Here in the north, many months are spent heating the home and an efficient system will make a large difference over time.  This post is Part one of a series on efficient home heating.  In part two I will show you how the water in our radiant system is heated.  Here's a hint:  Its big, yellow and likes to sit in the sky.  Stay tuned.      

More reading

There are lots of people talking/blogging about radiant heating technology.  It is found all across the country and applied in all sorts of buildings.  Here are some links.  Happy heating!

From the Federal Government

Wikipedia

A Hudson Valley-based private company specializing in radiant heating

A Vermont-based private company specializing in radiant heating

Lots of good radiant information here

What to do with all this wood?!

Hurricane Sandy happened over a month ago but the signs of her devastation still linger on: crushed roofs, fallen trees and the never ending buzz of chainsaws.  Of the thousands of trees that Sandy pushed over, many were next to people's homes and have since been cut up and removed.  Today's post highlights the role of dead wood in a forest ecosystem and stresses the ecological value of fallen debris. I will take you on a journey through the 'life' of a fallen dead tree:

Some of the many uses of fallen dead wood.  Dead wood is extremely valuable to the forest ecosystem as it provides food, shelter and a source of energy for future organisms.

A pile of sticks and branches makes great hiding places for animals

Once fallen, the crown of the tree (all the branches, limbs and twigs) rests on the ground.  Here it provides birds and mammals with shelter.  An impenetrable pile of sticks is difficult for us humans to move through but ideal for a warbler or a chipmunk hiding from a cooper's hawk.  The thin branches quickly break down and become incorporated into the soil's top layer where they continue to decompose and feed small critters.     

Bigger limbs fill up with insects, which attract hungry animals.

Larger limbs – like those pictured to the right – take years to break down.  They slowly begin to take on water and fill up with ants, beetles and grubs, which attract the pileated woodpecker and the northern flicker.  At every stage of decomposition, these dead limbs provide a unique habitat to decomposers which, in turn, prepare the wood for the next suitable suit of decomposers.  

Hollow logs attract a lot of animal activity.

Large logs may eventually become hollowed out.
These hollow logs act like little bunkers for forest mammals, used for eating in, hiding in and I like to think – napping in.  Exploring around one of these hollowed logs usually shows many sign of animal use such as scat (animal feces) and remnants of an animal meal.  

  

A 'snag' or standing dead tree.  

What about a dead tree that doesn't quite fall over? This type of dead wood (called a 'snag') is also very valuable to the forest ecosystem.  Snags will eventually fall to the ground and contribute pieces of wood to the soil but before they do, they act as a sort of wildlife condominium.  Notice the snag to the right.  See all the round holes?  These round holes happen when a rotted limb falls off or when excavated by a woodpecker.

A flying squirrel in a tree cavity.  Picture by me!

Once established, a tree cavity will be used for many years by squirrels, flying squirrels, owls, song birds and raccoons.  To read more about the importance of snags, see my Blog posts from March and April. 

There is a lot you can do with your downed wood to provide wildlife with useful habitat, shelter and food after a storm like Hurricane Sandy.  

1.  Leave logs on the ground to rot.  

2.  If you want to dress up your decomposing logs, you can turn them into rustic outdoor furniture.  

3.  Let broken trees stand and turn to snags.  

4.  Pile up downed branches to provide small animal habitat.   









At the Armstrong Education Center in Pound Ridge, NY I practice these different methods of using downed wood for wildlife.  As an added bonus you can expect to save some cash because these practices are often less expensive than paying a crew to cut, chip and haul your downed trees.  This is just another trick to Living Lighter on the Land.