AHRC Wheelchair Accessible Greenhouse

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AHRC Wheelchair Accessible Greenhouse

Final Design ReportMay 5th, 2008

Christopher Elizondo Primary Facilitator [email protected] Herrera Secondary Facilitator [email protected] Bressendorf Process Manager [email protected] Lee Relations Specialist [email protected]

E1102 Design Fundamentals Using Advanced Computing TechnologiesSec004

Jack McGourty-Instructor

Jose Sanchez-Instructor Nora Khanaria-Project Advisor

Ken Cronin-Project Partner Michael Kaplan-Project Partner



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Executive Summary

The AHRC, an institution that specializes in the assistance of others, came to the Gateway classwith a concept to help better their mission, facilities, and member’s well being. The creation of agreenhouse that is wheelchair accessible, low maintenance, and solar powered were the centralcriterion for a project that has now evolved into a preliminary design.

Through group meetings, in-class client visits, background research, and on-site familiarization,the team has been able to craft a problem space in which it can operate. The group understandsthe issues that present themselves when designing the greenhouse that is desired by the AHRC.A lack of direct sunlight and universal accessibility are the most pressing issues in the design of the structure. The American Disabilities Act dictates many of the dimensions required for universal accessibility to be attained. By adhering to these guidelines, the functionality of thespace is optimized, as any member of the AHRC would be able to operate the desiredgreenhouse.

These problems that initially faced the group have be surmounted by the application of problem

solving skills and basic design concepts. The design of greenhouse with a high angular slopingroof has been implemented in order to maximize the amount of incoming light from the Sun.

To harness the power of the sun, thermal units have been included in the final design. Water has been chosen as the medium that wills serve as the active component in the thermal storagevessel. The walls of the greenhouse have been assigned as brick on some portions on the outsideto provide a firm surround with polycarbonates on the other sections. This designs for maximumheat retention and longevity of the greenhouse.

An alternative solution is the presence of an outdoor patio; this will serve as an additionalfunctional space and a way to keep the present outdoor garden relevant. The design today iswithout a full patio and has not been included in the final design.

The group has compiled information in the following pages that examine aspects of the design project in a manner this is both scholarly and concise. The group has moved to a final design thatcompletes the desired parameters of the client and solves the issues presented by the environmentin which it will exist.



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Background Research

From inception of the AHRC Cyril Weingold greenhouse project, the team communicated withthe client and did much subsequent research to enhance the understanding of both the client’sneeds and simple necessities of a greenhouse. In context, the team was presented with the task of prototyping a greenhouse capable of being manufactured in order to allow for the facility’s

workers to have a recreational outlet. Due to the northeastern location of New York, a rather difficult growing spot nestled between a building and a slope, and previous failed attempts atsmall scale gardening, the client determined a greenhouse to be an effective choice.

To begin singling out a desirable, executable greenhouse designs the team underwent massresearch of the market climate. This yielded many points of consideration. The type of greenhouse requested by the client is referred to as a stand alone shed-type. The shed-typegreenhouse must be oriented to have its long axis running from east to west with a sloped sidefacing true south (Bellows). The team assessed the client’s allotted space for the greenhouse anddetermined that it suited such criteria. To reduce the effects of inevitably poor light distributionin the east-west oriented greenhouse, the north wall should be covered or painted with reflective

material (Bellows). The most notable aspect of this type of greenhouse is that the slope of itssouth wall can be altered depending on the latitude of the respective area. With New York beingin the north–eastern part of the United States, the slope must be between forty to sixty degrees,the steepest of possible shed-type slopes (Bellows).

Determined by the team to be perhaps the most important aspect of the greenhouse is its glazing.Glazing refers to the film of material applied to the inner walls of the greenhouse that permitslight to enter as well as prevents it from leaving. For the client’s needs it was decided that the best glazing to consider is triple walled polycarbonate. Things that make this a winningcandidate are its long life span, durability, and its favorable light transmittance and retention rate.

To specifically address the issue of minimal heat during colder months, most greenhouses havethermal heat storage vessel placed throughout the greenhouse. These vessels utilize a liquid’sability to retain heat longer than air and subsequently release it during periods where the heat of the surrounding air has long since left. The amount of vessels used varies greatly from region toregion and oftentimes even within a specific region it may come down to the type of plants, thetype of liquid, or personal preferences based on prior experience. For all practical purposes, theteam determined that the appropriate ratio for the client’s needs is 2 gallons of water per squarefoot of glazing on the south face. These vessels should be a dark color to absorb as much heat as possible.

Other points of heavy consideration for the team in the process of designing the greenhouseinclude: an insulated perimeter of the exterior foundation because the greenhouse will besurrounded by a parking lot; an insulated north wall because that is the wall where heat tends toexit; and the necessary procedures for preventing hot air from escaping through cracks and ventsduring winter months (Smith).

Cumulatively, this background research culminated in a feasible, practical greenhouse designoptimized for our client’s needs.



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Formal Problem Statement

The AHRC is an institution that lends a helping hand to mentally challenged and disabledmembers of its surrounding community. A current outdoor garden exists, but due to the presenceof high winds plant life has difficulty growing into healthy specimens. In an effort to create a

green area with social and therapeutic activities, the AHRC wishes to construct a greenhouse thatwill shield plant life from the harshness of the northeastern environment.

The available space where the greenhouse is to be constructed does not adhere to the criteria for a prime location of a greenhouse. The greenhouse will be built between two structures, one of which exceeds the height of the greenhouse, therefore limiting the crucial sunlight that is needed.This issue leads to a problem of choosing a wall material that both allows sunlight in at highrates, as well as an ability to hold and insulate the heat needed for homeostasis.

As the AHRC is a center for persons with varying disabilities, the projected design must alsoentail features that adhere strictly to the American Disabilities Act. To explain, the ADA

mandates dimensions that guarantee universal accessibility for all persons. The designdimensions must bear in mind the guidelines of the ADA so that all members of the AHRC cantake advantage of the greenhouse.

Design Specifications

From inception, the team was given several requirements that the client held high and that wereintegral to a successful greenhouse build. Firstly, the greenhouse must be capable of enduringharsh winters due to the fact that it will be located in New York City, a place with notablewintertime lows and harsh wind patterns. This means various approaches must be implementedto retain warmth or even independently warm the greenhouse. Conventional solutions for retaining heat utilize the storage of liquids within the greenhouse. The idea here is for theseliquid containers to absorb the natural heat permitted into the greenhouse. Liquids retain thisabsorbed heat much longer than the air inside the greenhouse and are thus able to release the heat back into the air over a longer period of time than the air itself can maintain its heat. As far asindependent heating systems are concerned it’s not uncommon to use specially designed heatinglamps to keep plants warm and facilitate plant growth.

Another preliminary requirement involved the greenhouse’s wheelchair accessibility. Aside from being a staple in modern society, this aspect is a natural choice for the AHCR due to itsmembership of people with varying physical and mental disabilities. Wheelchair accessibility isclearly an integral factor as it plays a large role in the general design of the greenhouse, mostnotably the size and distribution of objects and features inside the greenhouse.

Our final preliminary consideration was the request for the greenhouse to be low maintenance.This implied a greenhouse of relatively simple, resilient fauna that had its major needs fulfilledthrough automated systems. Such automatable processes are the water/ nutrients system of the plants in addition to the sterilization of the soil, both of which are essential for a greenhouse to persist.



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After meeting the client and actually visiting the site, the scope in terms of engineering wasexpanded leaving the team to reassess various issues. Though the team was provided with photographs upon meeting the client and told to fit the greenhouse within the parking lot, the truedimensions of the project were conceivable upon visitation. The size of the lot was in factsmaller than the team had anticipated causing the team to reconsider certain design requirements

defined in the preliminary phase. For example, the small size would limit the amount of liquidstorage containers permissible within the greenhouse. Generally it would be preferable to have asmany as possible during wintertime. Also, the accessibility to wheelchair would mean fewer lanes than initially thought possible, leaving us with perhaps an elongated single-lane greenhousewith plants on either side.

Upon visiting the site the lack of sunlight is immediately evident. From photos it appeared that anearby railroad was on level ground with the parking lot, but in actuality it overshadows itmeaning the greenhouse is blocked from both the AHRC building and railroad on adjacent sides.This lack of sunlight means that any sunlight that is received must be maximized. This will mostlikely result in a thin fiberglass resin used to permit light through. This also relates to the heat

retaining properties of the greenhouse because the resin used also determines the ability of thegreenhouse to retain heat as well as permit it. As the thickness of the resin , more heat that can beretained, but less sunlight is permitted to pass.

Some constraints associated with the team’s proposed problem statement include the need for alow cost/budget greenhouse as well as one that is of low maintenance.

Since the client is responsible for creating the necessary funding needed to put the greenhouse project in motion, the client has requested that our project solution be of reasonable economicfeasibility for the size of center such as the AHRC. By designing the greenhouse to universalaccessibility standards, we are in turn helping the client because this intrinsic feature makes the project more desirable in the debate for federal or private grants.

The major focal point of the final design is that the greenhouse will be wheelchair accessible. Ina closer examination of this constraint, one can see that these certain implementations have to bemodified to create a wheelchair accessible greenhouse. First the entrance must be wide enough toaccommodate for a wheelchair to enter. Also the tables which house the different plant-life needto be high enough for employees or visitors using wheelchairs to comfortably reach the plants.The client stressed the importance of the height of the tables. They even strongly suggested aspecific design of table that should act as a model for the group.

Final Designs

Having thoroughly refined the problem space and identified various aspects of the designspecifications and functional requirements, the team has crafted a final design that fully addressthe issues at hand and do so in the most effective way possible.

The greenhouse must endure New York City winter climate, which falls between temperate andextreme (3-5 winter months where average temperatures fall below freezing) (Smith). Adding tothe complexity of the situation is the little received sunlight of the specific location. The teamhas been designing a greenhouse optimized specifically for these conditions. A shed-type solar



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greenhouse has been designated the preferable choice. All greenhouses collect solar energy, butsolar greenhouses are designed not only to collect this energy but also to store heat in colder or cloudy weather (Bellows). Because the solar greenhouse is a shed-type, its long axis will berunning from east to west. Ideally the greenhouse should face within twenty degrees either sideof true south where it can optimally receive any kind of sunlight (Smith). The south facing wall

is glazed to collect optimum amounts of solar energy, while the north-facing wall is insulated to prevent heat loss (Bellows). To reduce the effects of poor light distribution the north wall will becovered or painted with reflective materials. Because New York City has an average sunshine percent range of only 49-65 percent, this was decisive (Smith). Also due to region, the shed-typegreenhouse must have a roof angle slope of anywhere between forty to sixty degrees (Bellows).This is preferable for northern latitudes. The glazing material used to permit sunlight and retainheat will be a polycarbonate multi-layer. There will be approximately 1.125 square feet of glazing for each square foot of floor space as determined to be an ideal proportion based onrecommended values for efficiency. To aid in the greenhouse’s ability to retain heat thermalstorage vessels will be utilized in addition to a possible furnace/heating lamps. If water is to beused as the thermal vessel then anywhere three to five gallons per square foot of south facing

glazing is favorable for New York’s latitude (Smith). Additionally, the general shed-typedimensions will easily fit into the 17x55 foot parking lot frame. Rounding out the build conceptsis the ground insulation. Because the greenhouse will be surrounded by asphalt it is has beendeemed a strong desire to provide ground insulation. This would ensure no heat loss due to afreezing ground. To implement this final idea all that is necessary is to have a strong, inch thick insulator surrounding the perimeter of the foundation, from footing to top.

Having completed the final design, the group strongly agrees this is the ideal build strategy theteam has constructed to address the problem spaces.

Alternative Solutions

During the course of our project to date, our team has explored many alternate solutions to our proposed project plan. One alternate solution is to not include the patio surrounding thegreenhouse. Since the addition of a patio surrounding the greenhouse adds a challenge to theteam’s proposed problem statement, neglecting to include it would reduce problem constraints.With these problem constraints reduced, the team can better deal with finding a solution thatmeets all of the client’s requirements without having to make too many sacrifices. Although theidea of not including a patio didn’t immediately sit well with the client, a compromise wasreached to include a patio-like area with tables and chairs. This reduced any further problemswith the constraints, yet it also caused the area allotted for the solar greenhouse to be reduced.

The group explored many solutions that dealt with the solar greenhouse itself. One such solutionincluded the actual type of greenhouse that we wanted to use. The team researched manydifferent types of greenhouses, from the different materials that they are made out of, to thedifferent layouts. All of the different types of materials that were explored could be alternatesolutions to our proposed project plan.

Another alternate solution that was looked into early on in the project planning process was theidea of rotating shelves. These shelves that house the plant-life would adjust heights using a



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simple pulley system. All users of the solar greenhouse could then adjust the height of the tablesto best suit their height specifications.

The next alternate solution dealt with the lack of solar energy for plant-life given the greenhouselocation. The team explored the aspect of using fluorescent lighting within the greenhouse in

order to sustain plant-life. Since this alternate solution clashed with one of many constraints thatarose from the proposed problem statement: low maintenance, the team turned to the idea of using solar panels instead. Due to this fact, the team decided to go with solar panels that weremade with a cheaper yet sun efficient material.

The last alternate solution explored dealt with the heating system of the greenhouse. The clientemphasized that the greenhouse must be able to retain heat in order for the various plant-life tosurvive the harsh winters of New York. At first the team explored using heating lamps, but likethe fluorescent lighting alternate solution, this solution fell within the low maintenanceconstraint.

Transition Plans and User DocumentationWhile the AHRC project description is unique in its own facets, the overall design of agreenhouse has been a customary, practical, and useful scenario for many other Gateway groupsin the past. A common thread combated by many of the design groups is the problem of heatretention because of the harsh winter climates here in New York City and the lack of sunlightduring those months.

While the group has chosen thermal storage vessels as a means of heating the interior of thegreenhouse during the winter periods, a future group could expand this project by optimizing theefficiency of gatherable sunlight, thereby reducing the strain on the storage vessels. By reducingthe need for these vessels through enhanced rates of light gathering, the amount of usable spaceincreases for plant life to flourish; inherently maximizing the original intent of a greenhouse.

If a future group needed an initial setting to begin the research for their project, the AHRC groupstrongly recommends the online Patent Office of the United States. The patent office providedfantastic beacon for guiding the most element aspects of the group’s design. The followingimages provided the inspiration for our designs:



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The design that has been produced by this AHRC group, while having solved issues that areapplicable to many other greenhouses, does not merit a paten application because the designinvolves a design that is currently a patent. Also the greenhouse has been made wheelchair accessible solely through the positioning of aisle ways and pre-specified door widths; inferringthat there is no new ‘idea’ being pursued in our designs which would need the protection of a patent. However the group does feel that it has put forth an effort in improving a design andimplementing it in an environment where it is needed.



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Appendix A Gantt Chart

Updated Gantt Chart



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Appendix B Product Design Specifications

Product title

AHRC Cyril Weingold greenhouse

Purpose

To provide a wheelchair accessible and interactive place of recreation for members of the CyrilWeingold facility

Special Features

Greenhouse will have automated irrigation and soil sterilization methods and be optimized for cold winter months

Need for product

The AHRC desires for a way for its members to have access to outside recreation during break times while enhancing the aesthetic appeal of the surrounding area.

Price

No given budgets for cost and operation of the greenhouse, but the most economical optionshave take priority yielding a market price of ~

Functional Requirements

System that cares for the plants is simple, but robust enough to sustain the plants.Effectively retains heat energyEffectively permits light to pass throughProvides independent heat sources

Physical Requirements

Conforms to size specifications put forth in the American Disabilities ActFits inside the client’s parking lotIs comfortable to navigate by foot or wheelchair Standard stand-alone shed shapeSemi-transparent

Service Environment

Greenhouse should be able to operate effectively during cold New York City winter whentemperatures often stabilize in the teens or low twenties.Weather resistant and durableAble to capitalize on what little light is available in area.



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Life-Cycle Issues

Automated care systems must have long term life of at least 10 years before any replacementnecessary

Easy to repair and/or exchange machinery partsGlassfiber sections of greenhouse must be simple to remove and exchange

Human Factors

Provides level of interactivitySafe for all people to useIntuitive to useEasy to train individuals on how to maintain greenhouse

Corporate Constraints

Construction will be carried out by contracted suppliers

Legal Requirements

Must meet all U.S. regulations No toxic materials to be associated with manufactureGreenhouse design may require license to U.S. patent 5,261,184



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Appendix C Budget Estimates and Materials Lists

Note: Cost estimates assume greenhouse dimensions of 12x30 feet. Values in parenthesesindicate cost per square foot (in $).

Steel tubes with 5 foot spacing for frame: $313.20 (0.87)

GlazingTwo Layers of 6mm Polycarbonate (10 year life): $432 (1.20)Inflation Equipment: $7.20 (0.02)Attachment Apparatus: $50.40 (0.14)

End WallsPolycarbonate sheet and frame (10-year life): $226.80 (0.63)Two welded aluminum back door (3 ft by 7 ft ea.): $50.40 (0.14)Assembly and installation: $486 (1.35)

Heating SystemGas unit heater (225,000 Btu): $90 (0.25)Control panel (1-stage heating/3-stage cooling): $54 (0.15)

Floor Grading Minimal Slope: $39.60 (0.11)Perimeter base--treated 2-inch by 6-inch lumber: $18(0.05)Plastic for ground cover (3oz/sq. ft.): $25.20 (0.07)

Power and Utility SourcesWell (15 gal/min): $338.40 (0.94)Basic irrigation hookups: $28.80 (0.08)Electrical service: $61.20 (0.17)Liquid propane gas tank hookup: $28.80(0.08)

BenchesCoated wire--14 gauge, 1-inch grid: $147.60 (0.41)Treated lumber frame, 2-inch by 4-inch: $79.20 (0.22)Cinder block legs: $25.20 (0.07)

Cooling and Ventilation SystemTwo-speed, ¾ hp, 42-inch fan: $90 (0.25)Four horizontal air flow fans: $50.40 (0.14)

Labor Costs: ~$2850 Note: Labor costs are based on estimates from similar greenhouses and assume one builder, one journeyman grade carpenter, one part-time skilled helper, and one part-time semi-skilled helper.



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Total Estimated Preliminary Budget: ~$5500Contingency Budget: ~$7000



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Appendix D List of Resources

Appeldom, Roger H. “Greenhouse construction and improved method of growing plants”Accessed: 16 Feb 2008. http://www.google.com/patents ?vid=USPAT5261184

Bellows, Barbara.Solar Greenhouses

, 2003< http://attra.ncat.org/attra-pub/solar-gh.html#designs> 16 February 2008,ATTRA Publication #IP142

Mann, Lisa Anderson. Total Landscape Care “Drip Irrigation”. March 2008. P.63-64

Smith, Shane. Greenhouse Gardener’s Companion. New York, 2000. Greenhouse Gardener’sCompanion. 2004. Charley’s Greenhouse and Garden. 21 March 2008< http://www.greenhousegarden.com/energy.html

AHRC Wheelchair Accessible Greenhouse

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