Habitat for Humanity - DOC by R4ESKfSG


									                      Habitat for Humanity
                    Final Report Spring 2001
                        Tuesday, April 24, 2001
                            Sponsor Contact:
                              Doug Taylor
                          Habitat for Humanity
                          420 South First Street
                           Lafayette, IN 47901


Prathima Venkatesan                  Jimmy Johnson
Email: prathima@purdue.edu           Email: johnso29@purdue.edu
Phone: (765)491-7850                 Phone: (765)742-8408
Lisa Major                           Nick Henthorn
Email: major@purdue.edu              Email: nicolae@purdue.edu
Phone: (765) 743-8013                Phone: (765) 495-5869
Donnie Austin                        Masaaki Atsuta
Email: donnie@purdue.edu             Email: atsuta@purdue.edu
Phone: (765) 743-6132                Phone: (765) 495-7646
Dave Russell                         Matthew Selvey
Email: drussel5@purdue.edu           Email: selvey@purdue.edu
Phone: (765) 464-1333                Phone: (765) 495-1262
Brian Waller
Email: wallerb@purdue.edu
Phone: (765) 746-5633
Executive Summary
Habitat for Humanity is a non-profit organization that builds houses for low-income families.
They build two, three, and four bedroom homes and customize them to the owner’s preferences.
Habitat sells the home for the amount it costs to build it and provides the owner with an interest
free loan. Prospective owners are required to work 250 hours for each adult member of the
family and attend workshops on home maintenance. The EPICS Habitat for Humanity Team is
divided into two main sub teams. The objective of the EPICS Architectural/Web Team is to
increase the efficiency of the home selection process and data management inventory at Habitat
for Humanity. The objective of the EPICS Energy Team is to provide efficient solutions to
reduce utility costs for the homeowner. This is done with the assistance of a software program
called Energy-10.

The Web Team works to make all information from the Architectural Team and Energy Team
available on the Internet. They have produced a World Wide Web page with three main parts for
use by Habitat for Humanity. The first is the Home Selection Guide (HSG), which serves as a
database where users can “point and click” to view different styles of homes. The Architectural
Team used existing Habitat architectural plans, and has produced a series of standardized floor
plans using 3-D Home Architect Deluxe 3.0 software. This software package allows the team to
design several houses quickly with inside and outside views of each home. The results are then
integrated into the HSG which displays the floor plans, exterior elevations, utility cost
breakdowns, and electrical wiring layouts of each home in the standardized book of plans.

The second part of the web page is the Home Construction Guide (HCG), which assists
construction managers by providing a construction timeline and bill of materials for each floor
plan in the HSG. The Architectural Team consulted the Building Construction Management
(BCM) Department at Purdue University to create a materials list for each home. With their
help, a simple program in Microsoft Excel spreadsheet was generated to produce accurate
materials lists. This program allows for easy evaluation of house designs and homebuilding
costs. In addition to the materials list program, a database of property that is owned by Habitat
for Humanity (i.e. leftover and donated materials) is being produced. This will enable the
Habitat for Humanity staff to cross-reference materials that they need to purchase and those that

they already have in their warehouse. The HCG also includes a Volunteer Tutorial that gives an
overview of tasks that volunteers or future Habitat homeowners might perform while building a

The third portion of the website is the Home Efficiency Options (HEO) page which serves as a
comparison between current energy options being used by Habitat and possibly more efficient
alternatives, as delivered by the Energy Team. The Energy Team brainstorms for new ways to
save the homeowner money on utility bills. This is done with the help of Energy-10 software.
With specific parameters of each house, Energy-10 simulates the weather of Indianapolis over an
entire year. The parameters of each home depend on the specifications of the home itself. The
first part of the semester was used to familiarize new team members with the Energy-10
software. The Energy Team concentrated on three main projects this semester. They were
carbon monoxide testing, thermal imaging scanning of existing Habitat for Humanity homes, and
installing programmable thermostats into Habitat for Humanity houses. Now that the team has a
good idea of how these modifications will affect the energy usage of each house, and how to
model them in Energy 10, they can be incorporated into the house variants. Energy-10 estimates
that a setback thermostat with central air-conditioning will save homeowners anywhere from
fifty dollars to one hundred dollars per year. Testing for carbon monoxide in the Habitat for
Humanity houses proved that the levels of carbon monoxide were well below those required by
EPA standards, which is 9 PPM over and 8-hour period and 35 PPM for a one-hour period.
Taking thermal images of the houses shows where the most critical energy losses occur. This
test proved that the IR camera would be a great asset to the Energy Team in the future.

Table of Contents
Project Tasks…………………………………………………………………………..…………..5
     Architectural/Web Team:
           3-D Home Architectural Deluxe 3.0 Floor Plans……………………….…….…...5
           Materials List Program……..……………………………………….…….………6
           Home Selection Guide……………………………………………..……….……..6
           Home Efficiency Options……………………………………….………...………8
           Home Construction Guide…………………………………….………….…….…8
           Point of Sale Database Project………..………………….………...…….…….….9
     Energy Team:
           Setback Thermostat………………………………….…………………..……….11
           Past Project Conclusions/Analysis………..……………...………………………13
           Thermal Imaging Scan of House Exterior…………..…….……………………..15
           CO Testing………………………………………………….……………………16
Transition Plan…………………………………………………………………………………...17
Semester Outcomes………………………………………………………………………………18

The EPICS program has been working with Habitat for Humanity for several years to assist
Habitat in improving their quality of service. The Habitat for Humanity EPICS team has been
able to provide Habitat with services that are helpful in the home selection process. After a
family is chosen for a new home, Habitat for Humanity provides the family with several choices
of home designs using the Standardized Book of Floor Plans and Home Selection Guide
produced during previous semesters. With the type of home selected, materials lists are used to
estimate the cost of the home, the Home Energy Options web page is used to discuss efficiency
options, and appropriate construction materials are purchased to start the building process.
During the building process, volunteer tutorials from the Home Construction Guide aide the
volunteers and homeowners in understanding the home construction process. This report
describes the creation of home designs used in the Standardized Book of Floor Plans and Home
Selection Guide, the steps required to produce materials lists and volunteer tutorials found in the
Home Construction Guide, and what is necessary in making the web page more easily navigable
and accessible to Habitat for Humanity and the affiliated members. Also included in the report is
a description of the structure and purpose of the newly developed database project that will help
increase the tracking of donations at Habitat for Humanity’s resale store.

In order to reduce the cost of owning the home, the Energy Team has conducted energy-
utilization analyses of current house plans and materials. According to Habitat for Humanity
International’s website (http://www.habitat.org), low-income homeowners pay (by percentage)
more for utilities than middle and upper class homeowners do. This fact illustrates the large
benefit that utility cost information and energy cost reduction can have for current and future
Habitat homeowners. The goal of the Energy Team is to reduce the costs of energy usage for the
homeowners by incorporating cost saving measures into Habitat for Humanity house plans. The
team’s main purpose this semester is not only to research more energy efficient ways to build
and maintain Habitat for Humanity homes, but also to re-analyze projects that the energy team
has done in the past, perform follow up analyses on them, and encourage Habitat for Humanity
to begin using the information and findings.

The Energy Team’s semester has been concentrated on three different projects. These projects
include thermal imaging of existing Habitat for Humanity homes, carbon monoxide (CO) testing,
and analyzing a setback thermostat. The thermal imaging project was comprised of helping
Habitat for Humanity locate “cold spots” in one of their remodeling projects. This task was
completed in early February. Taking thermal imaging pictures can be a big asset to the Energy
Team in the future. This will allow Habitat for Humanity and the EPICS Team to find the areas
of the house where heat loss occurs. The carbon monoxide testing was a safety project that was
done to determine if carbon monoxide levels were reaching dangerous levels in the houses, as
houses get more airtight. The main goal of the setback thermostat project was to re-analyze the
energy savings, and get them installed in the houses. The setback thermostats were modeled in
Energy-10 [5], revealing that they would be a good investment in Habitat for Humanity homes.
The thermostats were also installed into three different houses, two with central air-conditioning
and one without. Data will be collected on these beginning in the summer of 2001, and running
through the winter of 2001. To help the homeowners get more comfortable with the setback
thermostats, a tutorial was constructed to assist them in programming and everyday usage.

Project Tasks
Architectural/Web Team
The Architectural/Web Team’s objectives were established after consulting Doug Taylor of
Habitat for Humanity. He helped the team determine the number of floor plans that were to be
produced, how precise the materials list program would need to be, the desired amount of
information available in the Home Selection Guide, the level of information available in
volunteer tutorial portion of the Home Construction Guide, and the level of public accessibility
to the Home Efficiency Options page. All of these tasks are continuations of tasks from previous

3-D Home Architect Deluxe 3.0 Floor Plans:
In previous semesters a standardized book of floor plans was produced, which held thirty-one
floor plans of homes that Habitat might build for a future homeowner. This book is continuously
updated with more plans to reflect the different needs of both Habitat for Humanity and the
homeowners. Next semester, new floor plans will be produced as Habitat makes them available.

The generation of these plans, following the standards created in fall of 1999, will serve as a
teaching aide for the new members of the team who need to learn the 3D Home Architect
software. When completed, these plans will be added both to the Standardized Book of Plans
and the Home Selection Guide.

Materials List:
In the spring of 2000 a materials list program was developed using an Excel spreadsheet to
accurately calculate the quantity and cost of materials required in the construction of Habitat for
Humanity homes. With the help of John Sears, the construction supervisor, and Ray Dubea, the
repair supervisor, of Lafayette Habitat for Humanity, formulas were developed and entered into
this spreadsheet. The formulas that were developed estimate the quantity of each particular
building material used in a Habitat home and calculate the estimated cost for it to be built. The
spreadsheet will be capable of generating a complete materials list for a home based on the
answers to several basic questions about the house. Simple questions about the home layout,
locations of all major utilities, and extra items included beyond the standardized version of the
house plan will allow the calculation of a full materials list for the desired home. Habitat homes
are all very similar on the inside, but have subtle differences on the outside. This gives each
homeowner the feeling of having a unique house. Essentially there are five different front porch
styles (gable end offset, gable end centered, interior porch, side porch offset, and side porch
centered). Each of these variations requires special calculations. Although these calculations
have been developed in the past semester, a universal program that is applicable to all Habitat
style homes is still being developed. The material prices on the list were obtained from Von
Tobel Lumber and Hardware in Lafayette, Indiana. This is the supplier that Habitat for
Humanity purchases most of their lumber from. When all of the material prices are gathered, an
estimate of the total cost of the house can be obtained. Appendix I contains the most recent
version of the materials list program.

Home Selection Guide:
The house plans discussed previously are available in both the Standardized Book of Floor Plans
and the Home Selection Guide section of the web. The Home Selection Guide (HSG) is a point-
and-click interface with the different home plans available from Lafayette Habitat for Humanity.

The HSG presents the floor plan, exterior elevations, estimated utility cost breakdowns, and the
electrical wiring layout of each home. The homeowner will be able to compare operating costs
and functionality of different homes, and therefore be able to make a more informed purchasing
decision. By presenting the floor plans and exterior elevations, the homeowner will not have to
wait for an architect to prepare plans for each home. The homeowner will instantly be able to
see a computer-rendered image of what the home will look like. For each home size, there are
many design variations that are available. All of the variations of a particular size are shown
together on a common page so easy comparison can be made.

The HSG also presents a detailed analysis of what the utility bills will be for one year. The
analysis, which was performed by the Energy Team using the Energy-10 software package, is
presented in a simple to understand pie chart. The pie chart breaks down the cost of interior and
exterior lights, hot water, heating, cooling, and ceiling fans (Figure 1). There is an “other”
section that includes household appliances that do not fit into any of the previously stated
categories (a computer, for example).

                                             Figure 1
                                        HSG Cost Breakdown

Home Efficiency Options:
The Home Efficiency Options (HEO) pages
(http://epics.ecn.purdue.edu/hfh/web_project/heo/index.htm) contain a collection of studies made
by the Energy Team. The Energy Team, using the Energy-10 modeling software, performs
analyses of existing Habitat for Humanity house plans. House layouts and building materials are
entered, which allows for predictions of home energy usage and costs. After the analysis is
complete, the team modifies the houses in Energy-10 by varying construction and equipment
parameters to increase the efficiency of the energy use and thus decrease the yearly utility bills.
These modifications have included more efficient furnaces, central air conditioning, fluorescent
lights, longer roof overhangs, thermostat setbacks, and thicker walls. After these alterations are
made, the resulting utility bills are compared to those of the original house, and decisions are
made based on yearly savings, cost of the modification, and the pay back period (number of
years to payoff the increase in initial cost due to the construction change).

The HEO pages are an effort to display the results of these analyses to the Habitat for Humanity
directors and staff in a clear and concise manner. A template was constructed in order to
standardize the presented material and make it easy to browse. The template split each
efficiency option into five areas: objective, background, assumption, results, and conclusion.
Each option has its own page, which includes pictures, tables, charts, background material, and
the results of the analyses. By demonstrating the cost savings due to certain modifications, all
parties involved will be able to see the benefits of incorporating energy saving features into their
homes. Lower utility bills will allow the homeowners to save more of their money and spend it
on the upkeep of their homes, their families, etc.

Home Construction Guide:
The Home Construction Guide (HCG) pages
(http://epics.ecn.purdue.edu/hfh/web_project/HCG/INDEX.htm) were designed to assist those
who are involved with the construction process. Specifically, the HCG contains a construction
timeline, volunteer tutorials, and will contain a materials list for each floor plan. The
construction timeline has been created to serve as a resource for construction members. It is set

as a standard 10-week build for Habitat for Humanity of Lafayette. A section is highlighted to
show the days in which work should be done and completed for a specific task. Also, many of
the tasks listed have been set as links to a volunteer tutorial for the particular task. Possible
future improvements to the web page may include the capability of user inputs for specific dates,
more specific timelines, or the option to download the programs through the Internet. The
volunteer tutorials are divided into multiple sections based on their order in the home building
process. Each tutorial guides the reader through a step-by-step process necessary to complete the
task. Included in each tutorial are an equipment list and a brief outline of the process. This
semester, it was found that some of the tutorial links were broken or not functioning. The
volunteer tutorials were revised and repaired accordingly. Also, a survey was produced (See
Appendix II) with the help of Angel Tazzer, a Teaching Assistant with a B.S. in Information
Systems, in order to obtain feedback about the usefulness of the tutorials. Angel has experience
with gathering important information and was very helpful in deriving questions that would help
us to learn how to make the tutorials more useful. It was concluded from survey feedback that
next semester the tutorials would be equipped with diagrams and digital photographs taken from
building sites during construction. This will make it easier for volunteers to understand and
follow the tutorials. This section of the HCG is one of the sections that will undergo many
revisions over time according to the feedback received by Habitat for Humanity of Lafayette and
its volunteers.

Point of Sales Database Project:
Continuing from an idea proposed last semester by Habitat for Humanity, a database for the
Habitat resale store has been initiated. The purpose of the database is to organize donor and
product information and to make it more easily accessible. The resale store sells materials to the
general public that is donated by the community and not usable in Habitat for Humanity homes.
Information such as the name and address of the donor of a product and the product description,
condition, and price will be stored by the database. This will aid Habitat by simplifying the
process of organizing and maintaining the resale store. Two of the new members of the team,
Jimmy Johnson and Prathima Venkatesan, who are both studying Computer Engineering, have
completed the first design of the database. Through communications with the manager of the
resale store, Pam, and another store worker, Ray, the requirements for the database were

established. The database was separated into different sections according to the requirements
used for data searches and useful information for the organization of products, product types,
invoices, and donors. Relationships according to these sections have been established such as
there is one product type for many products, many products for one donor, one product for one
sold item, many products for one invoice, and also many sold items for one invoice. These
relationships are illustrated by a screenshot taken of the relationships tool for this database in
Microsoft Access 2000. In Figure A in Appendix III, the data tables can be seen with their data
fields inside of them. The lines between the tables point to the specific fields that are related.
All but one of the lines has a ‘1’ at one end and an infinity symbol at the other. These show the
relationships as described above, one-to-many relationships. The line without symbols
represents the one-to-one relationship described above between the products’ table and the sold
items’ table. A menu was created so that the user of the database can interface with the searches
and data entry forms without having knowledge of the database creation software or without
harming the database or its contents. This is shown by Figure B in Appendix III which is again a
screen shot taken from the database. There are three sections to the menu interface created.
There is a section, which contains a button for each data entry form. The donor entry form is the
top box in Figure C in Appendix III. The second section contains four buttons that each access a
query, and each query displays all of the records for one table except for ‘All Invoices’ button,
which combines the ‘Sold Item’ table and the ‘Invoice’ table. The ‘All Products’ query can be
seen as the middle box in Figure C in Appendix III. The final section of the menu is a series of
fields that are connected to different queries. To use this section, a search criterion is entered
into a field and then the button for that field is clicked. This will open a query displaying only
the records with the criteria entered. The ‘Product Type’ search criteria query is the bottom box
in Figure C in Appendix III. The database has reached a state of complete functionality, and it
would currently meet all of the resale store’s organizational needs. Due to the lack of time left in
the semester for the team to remain available if problems or bugs arise or to instruct the future
users of the database, the implementation of the database will occur at the beginning of next
semester. Also, EPICS will donate a computer with the Microsoft Windows operating system to
the resale store for the implementation of the database. Next semester there will also be the
research and design of a bar coding and labeling system to accompany the database and make the
resale store even more easily organized and maintainable.

Energy Team
Setback Thermostat:
A goal of the semester was to analyze and install setback thermostats into Habitat for Humanity
houses. Habitat for Humanity had fifteen Honeywell T8600 programmable thermostats donated
to them. Energy-10 was capable of modeling a setback thermostat in the houses, and the energy
cost savings associated with them. The parameters that Energy-10 required was the
corresponding temperatures for the heating and the cooling set back, and the time period that the
temperature change would take place. A list of the different parameters that Energy-10 needs,
and an example of the output, can be seen in Appendix IV. The thermostat was evaluated for
many different temperature changes, ranging from 70oF-58oF to 70oF-66oF. Energy-10 estimated
savings anywhere from fifty dollars to eighty dollars per year, depending on the ramping time
and the size of the house. A plot of the savings can be seen below in Figure 1.

                             Figure 1: Setback Thermostat Savings

The savings seen above correspond to a house of 987 square feet. Savings graphs for houses of
different square feet can be seen in Appendix V. Ramping time ranges from zero hours to four
hours. Ramping time is simply the time required to make the temperature change. As the chart
shows, the most savings can be obtained when the temperature change is instantaneous. As the
degree of temperature difference increases, the change in the amount of savings decreases. The
savings in Figure 1 is the total energy savings. The explanation to why the savings are not
equally spaced is that the other factors that determine the total energy savings do not change
linearly with temperature.

The second step in analyzing the setback thermostats was to install them into Habitat for
Humanity homes. With the help of Habitat for Humanity, three thermostats were installed. Two
of the thermostats were installed in homes with central air-conditioning. These houses are
located in Lafayette, at 255 Green Street and 1211 Washington Street. One thermostat was
installed at 1213 Washington Street, where central air-conditioning was not installed. Data will
be collected from these thermostats, starting in the summer, and running until the winter of 2001.
The data will be collected via utility bills. These will be compared to other Habitat for Humanity
houses in the area that do not have setback thermostats in them.

A concern was raised about the potential difficulty that homeowners might have in using the
setback thermostat, due to the lack of knowledge using new technology. In order to compensate
for this, the Energy Team constructed a tutorial to assist in the programming the daily use of the
setback thermostats. The tutorial goes through, step by step, the procedure for programming
each of the four basic programs that the thermostat contains. Along with the step-by-step
procedure, there are also illustrations in the tutorial to make the homeowner understand the
process easier. A copy of the thermostat tutorial is included in Appendix VI of this report.

Another concern was the kind of thermostat to purchase after Habitat for Humanity ran out of the
donated thermostats. Research was done to determine this. After research and comparing
different thermostats, the best choice would be to purchase more of the Honeywell T8600
programmable thermostats. Some of the factors in choosing an adequate thermostat were the
cost and the daily functions. A seven-day thermostat was preferred, so that the homeowner

could change the temperature on the weekends. There was also an option in changing the
temperature for each workday, however this option increased the price for the thermostat to
approximately one hundred dollars. The Honeywell T8600 can be programmed for the
weekdays, and then for Saturday and Sunday separately. These thermostats can be purchased for
approximately fifty dollars. Even at this cost, the payback period is still less than one year,
making it a wise investment for the future.

Past project conclusions/analysis:
One of the team’s priorities for this semester was to implement projects from previous semesters
into the Habitat for Humanity homes. Although there have been many good recommendations
made, they are not being used in the houses. Earlier this semester, the Energy team compiled a
list of all of the recommendations, good and bad, that have been made to Habitat for Humanity.
The list consists of the projects that were done and the overall recommendations that were made.

Some of the projects from previous semesters are being re-evaluated with the intention of
bringing about better and more accurate solutions. Recommendations might change due to
several factors. One of them is the change in the utility rates, while another could be an
inaccurate initial analysis or assumptions that are no longer valid.

For the future, the Energy Team intends to present the list of projects to Habitat for Humanity
and meet with them to see why these ideas are not being implemented in the houses. If they are
not being used, these reasons will be considered in the re-evaluation of previous ideas and
conclusions. The intent is to get them implemented into each new house, by meeting customer

The following page is the compilation of previous years’ work and the recommendations that
were concluded from them:

                  Habitat for Humanity EPICS Energy Team Conclusions
                                  (Fall 1996-Fall 2000)

Energy Team   Projects                                                    Recommendation
Fall 1996         Researched Solar Powered Fan                           None
                  Researched Geothermal Energy
                  Tested various lighting sources such as more windows
                   and fluorescent bulbs.
Spring 1997       More work on solar powered attic fan                   None
                  Tested more lights
                  Motion Sensor Lights
Fall 1997         Attic insulation was studied                           None
                  Continued work on solar powered attic fan
Spring 1998       Blower Door was developed                              None
Fall 1998         Solar cell study was finished                          No Solar Power
Spring 1999       Replaced 2x4 exterior walls with 2x6 walls.            No 2X6 Walls
                  Replaced 1-ft. overhangs with 2-ft. overhangs.         No 2’ Overhangs
                  Replaced window a/c with central a/c                   Yes Central Air
                  Replaced an 80% efficient furnace with a 90%           No 90%
                   efficient furnace.                                     efficiency

Fall 1999         Blower Door Testing                                    Yes Thermostat
                  House Modeling                                         Setback
                  Thermostat Set Back analysis
Spring 2000       Baseline Evaluation of New Houses                      Yes to:
                  Annual Utility Cost Breakdowns                         -Thermostat
                  Temperature Setback/Setup Analysis                     Setback
                  Window vs. Central Air Conditioning Analysis           - Central Air
                  Exterior House Wrap Analysis
                  Thermal Imaging Scan
Fall 2000         Cellulose vs. Fiberglass Insulation                    Yes to:
                  Caulking Wall Joints                                   - Cellulose
                  Attic Fan                                              - Caulk wall
                  Window Film                                            joints

Thermal Imaging Scan:
Another study conducted this semester involved the use of an Avio TVS-110 thermal imaging
camera. Habitat for Humanity is renovating a house, which was donated to them, and had made
changes to the insulation, windows and the exterior of the home. With the use of the thermal
imaging camera, the effects of these changes on the home were examined by studying the
exterior surface temperatures of the home before and after the changes.

The primary focus was on the windows, doors and exterior walls. The camera showed a
significant temperature gradient through the windows and around the doors, as expected. Colder
temperatures were found in the corners and below the windows, compared to the walls above
windows. These temperature differences ranged anywhere between 2 and 20 F. An exterior
wall that had new insulation and drywall installed increased the temperature by approximately
three degrees. An interesting observation was comparing the wall by a door and the border of
the door lacking insulation. There was a 20ºF difference.

The drawback from the analysis was performing it during the day. The sun shining through the
windows could have affected the readings. If the analysis were done in the evening, the camera
would have shown a more definite temperature difference. The indoor vs. outdoor temperature
difference was 30ºF. The temperature readings should be performed before dawn or after sunset
for the best analysis to minimize the outside interference. An example of a thermal image
picture can be seen below in the Figure 2. The areas of main interest are the red, and green
sections. These are areas of greater temperature differences, which means greater heat leak.

                               Figure 2: Thermal Imaging Scan
In addition to the results obtained from the thermal imaging scan, a calculation was performed to
determine the heat lost through a single paned window due to conduction. This was performed
assuming perfectly sealed windows and a thermal conductivity (k) of 0.058 W/mK [4]. The
driving equation used was:
where q is the conduction through the window, the area (A) is 15 ft2, the change in temperature
across the window pane ( T ) is 70F, and the thickness of the pane (l) is ¼ inches. This
calculation and the engineering model of the window can be found in Appendix VIII. The
conduction was found to be 266.6 Watts. From this result, it can be concluded that a significant
amount of heat is lost through the windows with this temperature gradient. This is also reflected
in Figure 2 above by the white coloring at the windows. However, the assumption that the
windows are perfectly sealed underestimates the heat losses from the Habitat homes.

CO Testing:
It was brought to our attention during a project partner meeting, that Habitat for Humanity was
concerned about the potential danger of unacceptable levels of carbon monoxide gas in their
homes. The reason for concern was due to the relative “tightness” of Habitat’s homes, and the
fact that there are not any carbon monoxide alarms in the homes. From blower door tests
conducted previously by our EPICS team, the number of air changes per hour in a home is
roughly 0.3 ACH (air changes per hour). ASHRAE standard 62 recommend that some form of
mechanical ventilation may be required for houses this tight. Carbon Monoxide gas buildup was

the greatest concern because at high concentrations (above 400 ppm [1]) it can be fatal. The
buildup of this toxic gas can be caused by any improperly vented combustion source such as gas
water heaters, stoves, and furnaces. One potential culprit brought to our attention was the
exhaust from the gas water heater. The water heater in Habitat’s homes exhausts an open flue
that relies on the fact that heated air is less dense than the surrounding air so it will rise through
the flue and exit the house. Habitat was concerned that when the dryer was turned on that the
pressure difference caused by the exhaust from the dryer actually drew air in from the flu instead
of venting the exhaust gasses.

To investigate this potential problem, our team decided to rent carbon monoxide testers and to
record levels of carbon monoxide gas in Habitat’s homes. When we arrived to test the homes,
(259, 263 Green St.), no carbon monoxide gas was detected because the windows were opened
so the house was well ventilated. So then it was decided to leave the CO tester in the home (259
Green) overnight while all the windows were closed and the dryer was running. When the CO
tester was retrieved, the maximum reading overnight was 3 parts per million (PPM). The EPA
standards [2] on safe CO gas concentrations are a maximum exposure of 9 PPM over and 8-hour
period and 35 PPM for a one-hour period.

After conducting on-site tests and analysis of infiltration models on the house it was concluded
that, as long as the gas appliances are operating correctly, no carbon monoxide buildup is likely.
The depressurization caused by running the dryer may pull air in from the flue depending on the
outside air temperature and exhaust air temperature. To determine this would require more
testing in the home [3].

Transition Plan
Next semester the new members will be familiarized with the software available and given
tutorials to follow in order to learn the programs they will need to complete their tasks. The
returning members of the Architecture/Web Team, Nick Henthorn, Jimmy Johnson, and
Prathima Venkatesan, will be working on projects that are currently under way. Floor plans will
be added as necessary using 3D Home Architect software. Pictures will also be taken at
construction sites and added to the website to aid the construction tutorials. The materials list

database, which was nearly completed this semester, will be completed, reviewed, and approved
by Habitat for Humanity staff. When this is completed, the Home Construction Guide will be
updated with the program. Nick Henthorn, who is most familiar with these projects, will lead
these tasks. As previously mentioned, the resale store database will be implemented next
semester and a bar coding system will be considered. This will be the primary responsibility of
Jimmy Johnson and Prathima Venkatesan. The web page will be updated and linked to the
existing Habitat web page by Jimmy Johnson and Nick Henthorn. By working together on these
tasks, the skills and knowledge of the returning members can be shared with new members.

The major area of concern for the Energy Team’s continuity/transition is the knowledge of the
Energy-10 software. This knowledge is being passed down to newer members that will be
returning, by teaching them how the program works, and giving them direct experience running
the program itself. All current members have organized the ‘T’ drive in the software lab. This
organization will help the returning members to teach the new members next year by examples
of the projects that we have worked on in the past. The Energy-10 software is more easily
learned by example, having someone explain the basic ideas behind the software and by reading
the manual. With one of our main energy group members returning, Brian Waller, continuity
will not be a problem.

New members will be an asset to our energy team because of their new ideas and vitality.
Project momentum will not be slowed by the fact that we are in a transition phase. We have
finished many of our analyses and we are now starting to implement various projects into the
Habitat homes. An example is installation of setback thermostats. Various other projects that
were included on our “team conclusions page” can also be reanalyzed and incorporated the same

Semester Outcomes
The overall project schedule for this semester can be found in Appendix VII. The majority of the
projects reached completion, while a few will continue into next semester. The main projects
that will continue into next semester are the materials list program and the data collection from
the setback thermostat study.

This semester, Nick Henthorn and Lisa Major served as leaders for the Architecture/ Web team.
Lisa’s responsibilities were to report team progress to the entire HFH team, and she also led the
materials list project with assistance from Nick. Nick is the project leader for the Architecture
Team and served to organize tasks. This semester, the materials list program received an initial
evaluation by John Sears at Habitat for Humanity and has be updated to remedy any inaccuracies
that were noted. Additionally, most of the materials were price estimated by Von Tobel Lumber
and Hardware in Lafayette, Indiana. A reevaluation by Habitat staff will be necessary to verify
that it produces an accurate representation of the materials required for the home construction
process. The volunteer tutorials have been updated and revised to provide a source of home
construction guidelines. Feedback concerning the volunteer tutorials has also been collected and
evaluated from Purdue University’s student chapter of Habitat for Humanity. The two new
members this semester, Jimmy Johnson and Prathima Venkatesan both worked diligently on the
new database project. The database project has seen completion this semester, and will be
implemented early next semester. The overall web page has been evaluated and changed
according to feedback from Habitat and its volunteers. Jimmy also served as the web-master for
the team, and completed the revisions to the web page. The address of the website containing this
information is http://epics.ecn.purdue.edu/hfh/web_project/.

Currently the energy team consists of five people. The team leader, Matt Selvey, acts as a
representative for the energy team in communicating problems and processes with other
members of the habitat epics team. The remaining members of the energy team have been
divided up to work on main projects throughout the year.

Thermostat Setback Analysis Installation: This was our first main project that has been
incorporated into a Habitat for Humanity house. The Energy Team had previous data showing
that setback thermostats would be advantageous in Habitat homes, but this semester Brian and
Matt reaffirmed this information and did a thorough examination of the energy savings and
various types of thermostats that could be installed in the habitat homes. Donnie was then able
to install three setback thermostats in habitat homes and setup three houses with Habitat for
Humanity to analyze their utility bills, and compare. Having the homeowner sign waivers to

release this information to Habitat for Humanity does this. Masaaki also did some research on
which thermostat would prove advantageous in the future.

CO Testing: This was a safety concern that was brought on by Habitat for Humanity. To
investigate this potential problem, Dave rented carbon monoxide testers and recorded the levels
of carbon monoxide gas in Habitat homes. After conducting on site tests and analysis of
infiltration models on the house, it is concluded that, as long as the gas appliances are operating
correctly, no carbon monoxide buildup is likely. The depressurization caused by running the
dryer is therefore not strong enough to overcome the pressure difference of the heated exhaust
gasses in the flue, so no unacceptable levels of carbon monoxide gas were recorded during our
Thermal Imaging: Habitat for Humanity also had an insulation concern in some of their homes.
With the help of a thermal imaging camera, Donnie helped Habitat for Humanity clarify different
areas of homes that may need better attention in the future. This device will also prove to be a
big asset to the Energy Team in the future, because this allows us to determine where different
areas of heat leak are in the homes.

Architecture/Web Team Members:
Lisa Major:
I have learned a great deal this semester in EPICS. By having the opportunity to co-lead the
Habitat for Humanity Team, I have discovered many of my strengths and weaknesses in the area
of leadership. I really enjoyed working with the other members of the team and interacting with
the Lafayette Habitat staff members a little more than last semester. It means a lot to me that we
can use our education to help members of the community and provide them with more affordable
homes. Although there were stressful times of learning to lead better and more efficiently, I’ve
taken a great deal away from this course.

Nick Henthorn:
My impressions of the EPICS program in general are good. I think that it is a useful and
beneficial class for anyone who takes it. I enjoyed working on the HFH team this year and was

happy with the people I worked with. I felt that some of the projects we were working on were
running out of steam, and so I look forward to starting next semester with new ideas and

Prathima Venkatesan:
This was my first semester in Epics and I had some initial expectations from the class. I knew
that I would get real-life experience that will help me in the future when I start working. I also
expected to work in a team of different people with different knowledge and opinions and get to
know each of them. Finally, I knew that whatever I was going to do for the team, I would
always be learning something new. All my expectations were satisfied. I got to interact with the
customer for our project and to understand what the needs were for them. Interacting with my
teammates helped me understand their major and what they can do to contribute to the team.
Finally, being able to start a new project allowed me to learn new applications and its usefulness
in satisfying the needs of the customer. Overall, I would say that being in Epics is a worthwhile
experience because it helps you develop many skills.

Jimmy Johnson:
The Habitat team wasn’t my first choice and from the description given I thought that it would
also not be beneficial or interesting. I am able to say now that I was wrong with my assumption.
After my semester with the Habitat team I believe that my leadership and communication skills
have grown. I have had the opportunity this semester to be the leader in a major project for the
Habitat team. This experience and the interdisciplinary communication have increased my real
world skills. Also, with Habitat for Humanity as our customer, I have had the experience now
with communicating across a technical barrier. By having a meeting every week, the project I
worked on this semester is different from every other project I have had before. With my other
projects there was one deadline, but this semester I had to report my project’s progression every
week. In a way, this kept me on my toes during the semester. All in all, I would say that I have
been surprised by EPICS, and that along with being a good experience, it was fun.

Energy Team Members:
Brian Waller:
I have had a mixed experience this semester in EPICS. At the beginning of the semester, and
into the middle, people seemed reluctant to work on progressing the projects. However, towards
the end of the semester, people really came around, and I think that our goals were
accomplished. I've learned to be more patient this semester, and more experience in teamwork.

Matt Selvey:
The semester started out fairly slow, while we were trying to get new ideas going and old ones
finished up. Once we started working though, I was really impressed by the amount of stuff we
got accomplished. We really pulled together as a team towards the end and finished up on some
projects that I didn't know if we'd finish. I thought our team worked very well together and it
would be interesting to see how much we could accomplish again next semester if we all stayed

Dave Russel:
This was my first semester in EPICS, and I was very excited to take the class. I liked the team I
was on, but I did not like the project that I spent most of my time on (CO testing). There was too
much sitting in the Engineering library doing research, with minimal results. I am still excited to
come back next spring. The team has great potential to really help Habitat and the people on the
team are the best.

Donnie Austin II:
I really enjoyed this semester. I was more involved with the habitat people and the epics
program through ESAC. The face-to-face work with Doug and John was rewarding because I
was able to see firsthand the accomplishments in semesters past. Also, it was an experience to
go into the homes and work with the people.

Masaaki Atsuta:
Since I expected this course community service course as the name suggesting, it was a little
disappointing. Whenever I saw the administration stuff, for instance, limiting students, or the

reputations of this course emphasized, my interest of it faded. I was depressed when I was
almost let go because of comments I wrote to ask for help about this course. Also, when I asked
Habitat people to come up with a new job for me, I felt they didn’t expect me (or us) very much.
I am also sure that Doug don’t want me to think that I work for them but he want me to think
they let me work for them and this is very depressing. Thus, my enthusiasm of this course now
is not high as in the beginning of this semester. However, some of the team members are very
nice to me and I feel that I should’ve worked harder and contributed to team more for these

The EPICS Habitat for Humanity Architectural / Web team is making progress to better provide
Habitat for Humanity with a product that is useful to their organization. The materials lists will
reduce the time it takes to actually start building the home. The database will serve to organize
and simplify the procedures associated with the resale store. The web page will provide an
easily accessible resource for all information required by Habitat throughout the home
construction process. Work between Habitat and the architectural / web team has resulted in a
complete set of standardized floor plans with material lists, a set of volunteer tutorials to describe
and illustrate each step in the home building process, a set of home efficiency options for home
construction, and a complete source of all information produced by the Habitat for Humanity
EPICS team. With the completion of this semester, the home building process should become
more efficient and easier for all members involved.

The Energy Team analyzed setback thermostats through the use of Energy-10. After simulating
them using Energy-10, they were installed into three of the existing Habitat for Humanity
houses. Data will be collected starting this summer, and will be completed next semester. To
make the homeowners more comfortable with the setback thermostats, a tutorial was completed
and will be delivered to Habitat for Humanity to give to each homeowner. The Energy Team
also tested for carbon monoxide levels in some of the Habitat for Humanity houses. After
conducting onsite tests and analysis of infiltration models on the house, it is concluded that, as
long as the gas appliances are operating correctly, no carbon monoxide buildup is likely.
Thermal imaging in the Habitat for Humanity houses was also completed, and will be a useful

tool in the future. Thermal imaging will allow people to see places in their home where heat is
escaping. These thermal losses are detrimental to the efficiency of the Habitat for Humanity
homes, and thermal imaging will help to recognize this loss of efficiency.


      [1] http://home.att.net/~cobusters1/Table.htm
      [2] ASHRAE Fundamentals Handbook. 1997 IP edition. Ch 25
      [3] ASHRAE Fundamentals Handbook. 1997 IP edition. Eq. 39, Pg 25.15; Eq. 28 p25.8
      [4] DeWitt, David P. and Frank P. Incropera. Fundamentals of Heat and Mass Transfer. John Wiley &
              Sons: New York. 1996 (Fourth Edition).
      [5] Designing Low-Energy Buildings: Passive Solar Strategies & Energy-10 Software 1.2. Passive Solar
              Industries Council: Washington, DC. 1996.


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