Chapter One Green Materials and Techniques. Chapter One: Objectives Upon completion of this unit, you will be able to – Identify energy efficiencies in

Chapter One

Green Materials and Techniques

Chapter One: Objectives

Upon completion of this unit, you will be able to– Identify energy efficiencies in green construction.– Recognize the various styles and uses of heat

pumps.– Distinguish between the different types of

insulation.– Compare and contrast U-Factors and R-Values.

Chapter One: Objectives (con’t)

– Review the details of an energy audit.– Identify the importance air quality.– Review sources of energy consumption for the

homeowner.– Define water use in terms of efficiency and

sustainability.

Chapter One: Key Terms

Argon: The most commonly used gas between panes in a thermal window. Blower door test: An energy test performed on a house by putting a large, calibrated fan in an exterior door, reducing the air pressure inside, and then noting where air flows into the house. Day lighting: The use of natural light, via positioning, skylights, etc. to reduce the use of artificial light in a building.

Chapter One: Key Terms (con’t)

Energy Audit: A process of examining the structure and systems of a house to determine its overall energy efficiency. Geo-Thermal Energy: is generated and stored in the earth. About 20% of the geothermal energy of the earth’s crust is from the origins of the planet; 80% is from the radioactive decay of minerals. A common example of geo-thermal energy is a hot spring, or geyser.


Grey Water: Water which has been used in a householdFor washing or showering, but not for flushing toilets.

Ground Source Heat Pump: A heating and cooling system whichuses the constant temperature of the ground beneath thesurface for heating and cooling. Ground temperatures in thelower 48 states of the United States vary from a low of 42º F inNorth Dakota to a high of 102º F in Idaho.


Infra-Red Thermal Camera: A camera used in homeinspection that can reveal “hot” and “cold” spots in ahouse, as well as water infiltration and leaks.

Insulation: Material used in construction to keepbuildings warmer in winter and cooler in summer, byblocking the flow of conditioned air (hot or cold) fromthe structure. Insulation is available in many forms.

low-E, or Low Emittance: A coating put on windowswhich stops some rays of the sun, but allows others topenetrate; allowing sunlight in but keeping the heat orcooling in the house.


Photovoltaic Shingles These are made from crystalline silicone-based materials, or in some cases, thin-film solar cells which are made of semiconductor materials. They are flexible and much less noticeable than standard solar panels. They absorb energy from the sun.


R-Value The measure of the efficiency of insulation in a structure. R-values measure thermal resistance, which indicates whether or not the inside temperature is flowing to the outside. The higher the R value, the better the insulating properties.


Solar panels Cells which use the sun’s light to either heat water or generate electricity.

U-Factor The measure of thermal conductivity in windows. Unlike R-values, where the higher number indicates better insulating properties, in windows, the lower the number, the better insulation the window provides.


Zero Net Energy: A building which uses zero energy from outside sources, and in many cases, emits zero net carbons.

Energy Efficiency

•A hallmark of green construction is that the homes are designed to save energy.

•Zero Net Energy homes create all the energy they need for heating and cooling.

Energy Efficiency (con’t)

Attaining net zero energy status, or having a highly energy efficient house, is accomplished by some or all of the following:– Positioning the building – Windmills– Ground source heat pumps– Solar panels and photovoltaic shingles– Day lighting, including skylights – Insulation and double- or triple-pane windows

Positioning a building

Positioning a building to take advantage of climate and prevailing winds is not new. For example:

- Enclosed/sun porches usually faced south or west to take advantage of the path of the sun.

- The south side of the home must be oriented to within 30 degrees due south.

Windmills

Windmills have been fixtures on some farms for generations, but today, wind farms are sprouting up in many places.

Ground Source Heat Pumps and Geo-Thermal Energy

We already defined Geo-Thermal Energy and and Ground Source Heat Pumps.– Note that “Ground source” refers to the constant

temperature of the earth at a certain depth, year round. - For example: In Pennsylvania, the average temperature is

50 degrees Fahrenheit. Using a ground source heat pump means that in the winter, when the outside temperature is 20º F, the heat pump only has to heat the air or water from 50º F, not 20º.

Ground Source Heat Pumps

There are a variety of styles.

• Closed loop system can be horizontal or vertical. Most of them require an anti-freeze solution to be circulated through the loops, which are either buried in the ground or submerged in water (like a pond).

• Another type of installation, called the “Slinky™”, has circular links. Vertical loops are often used for large buildings (e.g., schools, businesses) as they utilize less land.

Heat Pump Systems

• There are also open loop heat pump systems that use an existing body of water, either a well or surface body water (like a pond).

• The water functions as the fluid for the heatexchange system, and it circulates directly through the system.

Solar Panels

Solar panels are cells which use the sun’s light to either heat water or generate electricity.

- They have become more commonplace in the past decade.

- In sunny climates, like California and the southwest, solar companies are paying to rent roof space to install solar panels.

-Solar panels require some maintenance.

Photovoltaic Shingles

• This product generates energy from the sun.• It’s made from crystalline silicone-based materials or,

in some cases, thin-film solar cells of semiconductor material.

• When the sun’s energy strikes the photovoltaic material, a photon of light energy is absorbed, which then releases an electron.

• The electron produces a direct current (DC). Because most homes and businesses run on alternating current (AC), an inverter must be installed to convert the energy for use.

Day Lighting

•Day lighting is being used in both residences and other buildings. •These tubular skylights are easier to install, and reportedly have fewer issues with leaking around the roof than older skylights. •Reflective material is used within the tube to direct the light.

Insulation and Windows

•One of the major sources of heat or air conditioning loss in the average house results from poor or no insulation, and leaky or single pane windows.

R-Value

•To review, R-value is the measure of the efficiency of insulation in a structure. •R-values measure thermal resistance, which indicates whether or not the inside temperature is flowing to the outside. •The higher the R-value, the better the insulating properties.

Types of Insulation

•Blanket, batts, and rolls are made from fiberglass, mineral wool, plastic, or natural fibers.

•They can be applied to unfinished walls, floors, and ceilings as well as fitted between studs, joists, and beams.

Types of Insulation (con’t)

•Foam and rigid foam are made from polystyrene, polyisocyanurate, and polyurethane. •It can be used on unfinished walls, including foundation walls, floors, ceilings, and unvented low-slope roofs.


•Foam beads or liquid foam are made from the same materials listed above, as well as cementitious phenolic and polyisocyanurate polyurethane. •Foam beads or liquid foam can be applied to unfinished walls and are used in both new construction and major renovations.


• ICFs are foam boards or foam blocks that can be applied to unfinished walls, in new construction only.


• Blown-In - is usually blown-in using special equipment, or poured into a cavity.

• The materials used are cellulose, fiberglass, and mineral wool.

• It is a popular fix in existing homes to add insulation to places not insulated previously - which may also be irregularly shaped and have obstructions in the way.


• Reflective system insulation is made of foil-faced craft paper, plastic film, polyethylene bubbles, or even cardboard. It is used in unfinished walls and fitted between studs, joists, and beams.

• Rigid fibrous or fiber insulation is made of fiberglass or mineral wool. It is used in ducts in unconditioned spaces and often for places that must withstand high temperatures.


• SIP’s are foam-based or liquid foam insulation core, where sometimes the core is straw. These panels are built off-site and are installed together on the site.

• They are used in both commercial and residential construction.

Thermal Windows

• For energy efficient windows, the test is the U–factor, which measures thermal conductivity in windows.

• Unlike R-values, where the higher number indicates better insulating properties, in windows, the lower the number, the better insulating the window is.

Thermal Windows (con’t)

• Thermal windows can be double or triple pane.

• Argon is the most commonly used gas between panes in a thermal window - although upper end windows use krypton gas.


• low-E, or low emittance, is a coating on windows that stops some rays of the sun, but allows others to penetrate.

• It allows short-wavelength sunlight to pass through, but reflects back the long-wavelength infrared radiation.

• In winter, it brings in the warmth from the sun, and keeps the warmth in the house.


• The U-factor rule is “the lower, the better.” Examples of U factors:– Single glass, aluminum frame: 1.30– Double glass, 1/2” air space: .81– Double glass, low-E, 1/2” space with argon:

.64– Triple glass, low-E in two panes, 1/2” spaces with

argon: .53

Retrofitting and Remodeling

When retrofitting and remodeling a home, the first step is often determining where the major energy losses are occurring.

• Energy audits• Infra-red thermal camera • Blower door test

Energy Audits

• An energy audit is a process of examining the structure and systems of a house to determine its overall energy efficiency.

• There are two commonly used methods of energy assessment:– Photographing the house with an infra-red

camera– Doing a blower-door test

Infra-red Thermal Camera

• Infra-red thermal camera is a camera used in home inspection that can reveal “hot” and “cold” spots in a house, as well as water infiltration and leaks.

• These cameras can detect variations in temperature, and pinpoint where insulation is missing, or inadequate.

Blower Door Test

• The test is performed by installing a powerful fan into the frame of an exterior door.

• When the fan is activated, it pulls the air out of the house, which lowers the interior air pressure. Then, the higher outside air pressure flows in, revealing unsealed cracks and openings.

Air Quality and Ventilation

• Houses should be relatively air tight, but they also need to have good ventilation.

• Indoor air pollution can also be caused by: cigarette smoke, smoke from wood stoves, and use of Volatile Organic Compounds (VOCs) in building or furnishing materials.

• According to the EPA: “Indoor air pollutants have been ranked among the top five environmental risks to public health.”

• Source: www.epa.gov/region/communities/indoorair.html.

Energy Costs

• Heating is the largest category of energy cost for a homeowner (about 45 percent).

• Water heating accounts for 18 percent and can be fueled by any of the following sources:– Electric– Gas (propane or natural)– Oil– Furnace or boiler (gas or oil)– Solar

Water Heat

Water is heated in one of two ways: • Stored (the most common) - the water heater

heats and holds the hot water until it is needed.

• Instantaneous - the hot water is on-demand.• Hot water fueled through a furnace or boiler is

also known as a tankless system.

Cooling

• Cooling accounts for 9 percent of energy costs. – This is based on a snapshot of the United States as

a whole - obviously, in the Southern states, heating costs are less and cooling costs are more.

• Homes can be air conditioned via window or wall air conditioners, or by central air conditioning.

Lighting and Electronics

• The next two largest categories of energy cost are lighting and computers/electronics.

• The U.S. Government has been on course to phase out incandescent light bulbs. Several alternatives include:– Compact fluorescent lamp (CFL) – LED (light emitting diodes)

Water Use

• Water use, like the use of any kind of fossil fuel or electricity generated by a fossil fuel, falls under both the efficiency and sustainability categories.

Water Use (con’t)

Water conservation techniques include:– Use of a rain barrel or cistern to collect rain water.• A cistern is a container, with a waterproof lining, for

holding liquids - like rainwater.

– Planting native plants, mulching heavily, and only watering the roots.

– Reusing grey water - water that has been used in a household for washing or showering, but not for flushing toilets.

Water Use (con’t)

Water conservation trends also include:• Low flow shower heads• Dual flush toilets• Waterless urinals• Highly efficient washing machines and

dishwasher

Sustainability

• Sustainability applies to all materials and natural resources which can be depleted, which includes:– Lumber– Water– Fossil Fuels– Land– Building materials

Sustainability (con’t)

• Lumber is arguably a renewal resource. • Sustainability affects lumber in regard to rare

lumbers (from rainforest settings), since those trees take a long time to grow. – Bamboo, which grows quickly, may not make the builder’s

supply list for a new house because of the fossil fuels used to transport it.

• Forest Stewardship Certified Council Lumber - lumber that is responsibly grown and harvested.


• Water is at a premium in some parts of the United States as the last decade has seen serious droughts.


• For example: The Energy Policy Act, which consists of 27 titles, was passed in 1992 by Congress. It set policy regarding energy consumption and efficiency. In 1994, part of this act specified the installation of low-flush toilets, that flushed about 1.6 gallons of water per flush. This saved a great deal of water since pre-1994 toilets used approximately 3.4 gallons of water per flush.


• Previous slides and examples in your textbook outline how water can be saved in green construction in a number of ways (eg: low-flow toilets).


• Fossil fuels, which are coal, oil, natural gas are not renewable sources of energy.

• A green feature of a house is to rely very little, if at all, on non-renewable fossil fuels.

• Green living takes into account the carbon footprint of the occupants of the house, including how they get from the house to work and school (eg: walking or driving).


• Land is a non-renewable source. • For this reason, environmentalists and green

builders oppose using farmland for building, preferring to reclaim land previously used for construction.


• Many building materials can be recycled.• Companies who tear down houses can often

salvage useable items and resell them for use. – For example - in Williamsport, PA approximately

300 homes, all about 90 to 120 years old, were torn down to make way for a massive hospital expansion. The company who demolished the houses salvaged doors, flooring, windows, railings, cabinets, and resold them.

Chapter Summary

In this chapter, we discussed:• Building methods and techniques used to

create green homes. • Energy efficiency, including net zero homes, is

now a constant in the real estate market. • Buyers are beginning to realize the value of

energy assessments for existing homes.

Chapter Summary (con’t)

• New innovations in building materials and techniques are common; for example, photovoltaic shingles, CFL light bulbs, and on demand hot water systems.

• Sustainability is an important issue in green construction, from the materials used to how much water is consumed.

Chapter 1: Quiz

1. The source of the largest energy use in the average American home is for

a. cooling.b. heating.c. lighting.d. refrigeration.

Chapter 1: Quiz

1. The source of the largest energy use in the average American home is fora. cooling.b. heating.c. lighting.d. refrigeration.

Chapter 1: Quiz

2. The most common gas found between panes in thermal windows is

a. argon.b. helium.c. kryptonite.

d. radon.

Chapter 1: Quiz

2. The most common gas found between panes in thermal windows isa. argon.b. helium.c. kryptonite.

d. radon.

Chapter 1: Quiz

3. With respect to the U-value of windows, which is correct?

a. The higher the U-value, the higher the energy efficiency.

b. The lower the U-value, the higher the energy efficiency.

c. The lower the U-value, the more likely the window is to leak.

d. Windows are rated using R-ratings.

Chapter 1: Quiz

3. With respect to the U-value of windows, which is correct?a. The higher the U-value, the higher the energy

efficiency.b. The lower the U-value, the higher the energy

efficiency.c. The lower the U-value, the more likely the

window is to leak.d. Windows are rated using R-ratings.

Chapter 1: Quiz

4. A home has poor indoor air quality. Which of the following most likely did NOT contribute to the poor indoor air quality?

a. electric on demand water heaterb. owner’s smoking of cigarettes in the housec. use of VOCs in building materials and furnishingsd. wood stove in the basement

Chapter 1: Quiz

4. A home has poor indoor air quality. Which of the following most likely did NOT contribute to the poor indoor air quality?a. electric on demand water heaterb. owner’s smoking of cigarettes in the housec. use of VOCs in building materials and furnishingsd. wood stove in the basement

Chapter 1: Quiz

5. Ground source heat pumps work on the principle that, throughout the United States,

a. hot springs and geysers are present to provide heat.

b. ponds are available for an open loop system.c. the temperature below the frost line is an even

50º.d. the temperature below the frost line is constant

year round.

Chapter 1: Quiz

5. Ground source heat pumps work on the principle that, throughout the United States,a. hot springs and geysers are present to provide

heat.b. ponds are available for an open loop system.c. the temperature below the frost line is an even

50º.d. the temperature below the frost line is constant

year round.

Chapter 1: Quiz

6. A buyer is considering buying an older home but is concerned about the energy use. Which of the following would be MOST useful to the buyer?

a. all-inclusive energy audit, including an infrared camera use and a blower door test

b. evaluation of the current owner’s utility billsc. online review of the house via websited. visual inspection by the appraiser or agent of the

property

Chapter 1: Quiz

6. A buyer is considering buying an older home but is concerned about the energy use. Which of the following would be MOST useful to the buyer?a. all-inclusive energy audit, including an infrared

camera use and a blower door testb. evaluation of the current owner’s utility billsc. online review of the house via websited. visual inspection by the appraiser or agent of the

property

Chapter 1: Quiz

7. Which of the following types of insulation would BEST be suited to an area where the insulation needs to go around existing barriers, and fill an irregular space?

a. battsb. blown inc. ICFsd. rigid foam

Chapter 1: Quiz

7. Which of the following types of insulation would BEST be suited to an area where the insulation needs to go around existing barriers, and fill an irregular space?a. battsb. blown inc. ICFsd. rigid foam

Chapter 1: Quiz

8. One of the down sides of photovoltaic shingles is that they

a. do not blend in with the other shingles.b. do not work.c. produce DC current, which requires an alternator

on site to convert to AC current.d. require maintenance.

Chapter 1: Quiz

8. One of the down sides of photovoltaic shingles is that they

a. do not blend in with the other shingles.b. do not work.c. produce DC current, which requires an alternator

on site to convert to AC current.d. require maintenance.

Chapter 1: Quiz

9. Currently, which of these is being phased out by the U.S. Government?

a. coal stovesb. compact fluorescent light bulbsc. incandescent light bulbsd. tanked hot water heaters

Chapter 1: Quiz

9. Currently, which of these is being phased out by the U.S. Government?a. coal stovesb. Compact fluorescent light bulbsc. incandescent light bulbsd. tanked hot water heaters

Chapter 1: Quiz

10. A double pane, low-E window with a 1/2” space filled with argon is ____times as efficient as a single pane window in an aluminum frame.

a. 2b. 2.5c. 3

d. 4

Chapter 1: Quiz

10. A double pane, low-E window with a 1/2” space filled with argon is ____times as efficient as a single pane window in an aluminum frame.a. 2b. 2.5c. 3

d. 4

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Chapter One Green Materials and Techniques. Chapter One: Objectives Upon completion of this unit, you will be able to – Identify energy efficiencies in