Rd instruction 1924-a table of Contents




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GUIDE 2

Rural Development DESIGN GUIDE

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RD Instruction 1924-A

Guide 2



FOREWORD

This Guide is designed to assist Rural Development personnel determine and evaluate design features which are not fully described in local building codes or the development standards for rural housing proposals requesting financing from the Agency. Housing proposals should address the liveability and marketability objectives in the Rural Development Manual of Acceptable Practice (MAP) and this Guide. Substantial deviation from these objectives should be evaluated in the appraisal process and reflected in the present market value of the proposed housing.

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GENERAL TABLE OF CONTENTS


Page

Chapter 1 - SPECIAL DESIGN 1 - 1


Chapter 2 - RESERVED 2 - 1
Chapter 3 - SITE DESIGN 3 - 1
Chapter 4 - BUILDING DESIGN 4 - 1
Appendix A - GLOSSARY OF HOUSING TERMS A - 1
Appendix B - ABBREVIATIONS B - 1

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CHAPTER 2 RESERVED

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TABLE OF CONTENTS


CHAPTER 3 SITE DEVELOPMENT PAGE


300 GENERAL 3 - 1

300-1 REFERENCES 3 - 1


301 LAND USE 3 - 2

301-1 GENERAL 3 - 2

301-2 BUILDING LOCATION AND ARRANGEMENT 3 - 2

301-3 INTENSITY OF DEVELOPMENT 3 - 3

301-4 NOISE CONTROL 3 - 3

301-5 SITE SURROUNDINGS 3 - 3

301-6 BLOCKS 3 - 4
302 UTILITIES 3 - 4

302-1 GENERAL 3 - 4

302-2 INSTALLATION 3 - 4
303 STREETS 3 - 6

303-1 GENERAL 3 - 6

303-2 TYPES OF STREETS 3 - 6

303-3 STREET PATTERNS 3 - 7

303-4 SUB - TYPES 3 - 11

303-5 DESIGN FEATURES 3 - 14

303-6 STREET CONSTRUCTION 3 - 14

303-7 RELATED CONSTRUCTION 3 - 19

304 GRADING DESIGN 3 - 19

304-1 GENERAL 3 - 19


305 DRAINAGE 3 - 20

305-1 GENERAL 3 - 20

305-2 SWALES AND OPEN DITCHES 3 - 20

305-3 STORM SEWERS 3 - 20

305-4 SUBSURFACE DRAINAGE 3 - 20
306 THE PROPOSED SITE 3 - 21

306-1 GENERAL 3 - 21

306-2 TOPOGRAPHY 3 - 21

306-3 GROUND WATER 3 - 21

306-4 LOT LAYOUTS 3 - 21

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307 YARDS AND BUILDING SETBACK DISTANCE 3 - 25

307-1 GENERAL 3 - 25

307-2 SIDE AND REAR YARDS 3 - 25

307-3 DISTANCE BETWEEN BUILDINGS 3 - 26

307-4 BUILDING STREET SETBACK DISTANCE 3 - 26
308 PARKING AREAS 3 - 27

308-1 GENERAL 3 - 27

308-2 NUMBER OF SPACES 3 - 27

308-3 PARKING BAYS 3 - 27


309 WALKS 3 - 28

309-1 GENERAL 3 - 28

309-2 PUBLIC OR COMMON USE WALKS 3 - 28

309-3 ENTRANCE WALKS 3 - 28

309-4 CHEEK-WALLS 3 - 28

310 SERVICES 3 - 28

310-1 GENERAL 3 - 28

310-2 ACCESS 3 - 29

310-3 GARBAGE AND REFUSE 3 - 29

310-4 SERVICE SCREENING 3 - 29


311 PLANTING DESIGN 3 - 29

311-1 GENERAL 3 - 29

311-2 LAWNS 3 - 29
312 SITE DETAILS 3 - 29

312-1 GENERAL 3 - 29

312-2 LAUNDRY DRYING AREAS 3 - 30

312-3 WALLS AND FENCES 3 - 30

312-4 OUTDOOR LIGHTING 3 - 30
313 COMMON USE FACILITIES 3 - 30

313-1 GENERAL 3 - 30

313-2 RECREATION 3 - 30
314 HILLSIDE DEVELOPMENT 3 - 31

314-1 GENERAL 3 - 31

314-2 MANUFACTURED SLOPES 3 - 31

314-3 LOT AREAS 3 - 31

314-4 LOT WIDTH 3 - 32

314-5 WALKWAYS 3 - 32

314-6 STREET CONSTRUCTION 3 - 32

314-7 DRIVEWAYS 3 - 32

314-8 LIGHTING 3 - 32
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CHAPTER 3

SITE DEVELOPMENT

300 GENERAL


Site development includes the arrangement of all site facilities necessary to create a safe, functional, convenient, healthful, durable and attractive living environment for residents.
This chapter gives basic guidelines and considerations to be used by an applicant or builder-developer in planning subdivisions, individual sites, and Multi-Family Housing developments. Site development requirements are prescribed in RD Instruction 1924-C, Exhibit B.
300-1 REFERENCES
There are a number of references that may be helpful in planning site development. The following is a partial listing of such references:
(a) Manual of Acceptable Practice: RD 4930.1
(b) Architectural Graphic Standards; American Institute of Architects
(c) Handbook of landscape Architectural Construction; American Society of Landscape Architects
(d) Grade Easy - An Introductory Course in the Principles and Practices of Grading and Drainage; American Society of Landscape Architects Foundation
(e) Urban Hydrology for Small Watersheds; SCS-TR-55
(f) A Method of Estimating Volumes and Site Runoff in Small Watersheds; SCS-TP-149
(g) Handbook of Channel Design for Soil and Water Conservation; SCS-TP-61
(h) Simplified Method for Determining Floodwater Retarding Storage; SCS-TR-3
(i) Hydrology; SCS-NEH-Section 4
(j) Residential Streets; Urban Land Institute, American Society of Civil Engineers, National Association of Home Builders;
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(k) Residential Storm Water Management; Urban Land Institute, American Society of Civil Engineers, National Association of Home Builders;
(l) Residential Erosion and Sediment Control; Urban Land Institute, American Society of Civil Engineers, National Association of Home Builders;
(m) Residential Development Handbook; Urban Land Institute;
(n) Geometric Design Guide for Local Roads and Streets; American Association of State Highway Officials;
(o) A Guide for Accommodating Utilities on Highway Rights-of-Way; American Association of State Highway and Transportation Officials

301 LAND USE


301-1 GENERAL
Land use planning for all housing should relate appropriately to all site conditions and to the existing or permissible development of adjoining properties.
301-2 BUILDING LOCATION AND ARRANGEMENT
301-2.1 The use of a proposed site should be planned for buildings so

arranged on the site and having characteristics which assure

that:
(a) The property has adequate visual appeal.
(b) The property can be operated and maintained at costs reasonably related to income.
(c) The land use and other site planning standards are met, and
(d) Zoning and other local regulations are complied with.
301-2.2 The building arrangement and location should relate well:
(a) To the natural topography, avoiding deep cuts, fills, excessive foundation wall depth, unnecessary steps and steep access gradients.
(b) To climatic conditions, assuring maximum benefit from and protection against, as appropriate, sun, wind, temperature, precipitation, etc., and

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(c) To attractive on-site and off-site views.
301-2.3 The building location, arrangement, and orientation should

assure adequate open space for outdoor living areas, all facilities, services, amenities, and for interior natural light, air and privacy. Undesirable outlook from windows of rooms for daytime use should be avoided.


301-3 INTENSITY OF DEVELOPMENT
The number, size and type of dwelling, along with parking spaces, recreation and other open spaces should be determined by the characteristics of the site, its location, land cost, and acceptability by the community.
301-4 NOISE CONTROL
Through the use of site design techniques such as building location and orientation, window placement and the use of barriers, predictable undesirable site noise should be tolerated to as close to clearly acceptable levels as practicable. See HUD-PDR-735 "Noise Assessment Guidelines."
301-5 SITE SURROUNDINGS
The site design should be arranged when practical and possible to harmonize with the complement functions and appearance of site surroundings which have a significant bearing on the site. Where the surroundings of a site have incongruous functions or undesirable visual conditions, buffers or screen devices sufficient to separate or modify these unpleasant conditions should be provided.
301-5.1 No site should be developed where external influences on the

site create conditions undesirable for residential use such as:


(a) Hazardous landslides, falling rock, or other unstable slope conditions due to site topographic or geologic conditions;
(b) Unusual terrain features such as steep slopes, abutting rock formations, or other conditions affecting construction, drainage, or livability;
(c) Unusual risks from natural hazards such as geologic faults, flash floods, volcanic activity, mudslides or fires, or from the presence of ponds, or hazardous terrain features;
(d) Unwarranted risks from man-made hazards such as the presence of hazardous materials, or the presence of potentially hazardous industrial activity or material in the surrounding area;

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(e) Nuisances from odors, vibrations, unsightly areas, nearby landfills, inconvenience or other nuisances.
301-6 BLOCKS
301-6.1 The lengths, widths and shapes of blocks should be determined

with due regard to:


(a) Provision of adequate building sites suitable to the special needs of the type of use contemplated.
(b) Zoning requirements as to lot sizes and dimensions.
(c) Needs for convenient access, circulation, control and safety of street traffic.
(d) Limitations and opportunities of topography.
301-6.2 Block lengths generally should not exceed 1600 feet nor be

less than 400 feet.


301-6.3 Blocks should be wide enough to allow two tiers of lots of

minimum depth. However, where this would require lots to front on an arterial street or highway or where topographical conditions of the size of the property prevent two tiers of lots, single lots with necessary alterations may be used.


301-6.4 When double tiered blocks are over 800 feet in length, a 10-foot

wide pedestrian access easement is recommended near the center of the block for circulation or access to schools, playgrounds, shopping centers, transportation and other community facilities.


301-6.5 Intersections with arterial streets should be held to a minimum

and preferably spaced at least 1000 feet apart.


302 UTILITIES
302-1 GENERAL
The site design should provide for all utilities in a manner which allows economy in construction and maintenance.
302-1.1 The site design should be arranged to recognize existing

easements, utility lines, etc., and permit connection to existing facilities where necessary for the proper functioning of drainage and utilities.


302-2 INSTALLATION

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303-6.1.1 All driving and parking areas should have sufficient gradient

to provide for adequate drainage. Storm sewers or drainage ditches should be provided to accept surface run-off and prevent pooling on roadway areas. In arid or semi-arid areas, the roadway may be designed with an inverted crown to accommodate occasional run-off. Subsurface drainage should be adequate to maintain a stable subgrade.


303-6.1.2 The subgrade should provide a stable platform for the base and

wearing surface under all anticipated geologic, hydrologic and climatic conditions. The subgrade should be judged acceptable according to soil type and anticipated traffic loads.


(a) In-place soil should not contain amounts of muck, clay, veritable matter or other elements which will detrimentally affect the structure of the roadway. Where these elements do occur the stabilization procedures outlined below should be followed. The subgrade should be thoroughly compacted to a density necessary to support the roadway.
(b) Fill material should be free from muck, clay, vegetable matter or other elements which will detrimentally affect the structure of the roadway. All fill should be compacted according to the characteristics of the acceptable in-place soil, the fill soil and anticipated traffic loads. Where extensive fill is required, the design should be executed by a qualified professional engineer.
(c) Compaction should be adequate for the design load of the roadway plus a 25 percent impact load. State or local regulations should be followed in the determination of acceptable practice.
(d) In areas where soil in-place is not adequate for use as a street subgrade, appropriate stabilization should be utilized. Soil cement, lime and calcium chloride are the most commonly used stabilization elements and their use for each particular case should be determined by a competent engineering study or by local regulations.
303-6.1.3 The base should be constructed in a manner which will provide a

suitable course for the application of the final surfacing. The composition and depth of the base should be appropriate for the type and amount of traffic anticipated. The types listed below are generally acceptable base materials and others may be used according to local conditions.


(a) Gravel Base. This base should consist of gravel and filler constructed on a prepared subgrade. The material should be free from organic matter and lumps or balls of clay; and such
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Material should be removed and replaced with approved material. The base thickness should be determined by the projected road usage and should be placed in layers not to exceed three (3) inches in thickness after compaction. The base course material should not be deposited or shaped on a frozen or thawing subgrade or during unfavorable weather conditions.
(b) Crushed Stone Base. This base should consist of crushed stone constructed on a prepared subgrade. The material should consist of hard, durable particles or fragments of stone, free from an excess of flat, elongated, soft or disintegrated pieces, dirt or other objectionable matter. The base thickness should be determined by the projected road usage and should be placed in layers not to exceed three (3) inches in thickness after compaction. After the coarse aggregate has been thoroughly compacted, choker stone should be gradually applied to fill all voids. No base course material should be deposited or shaped when the subgrade is frozen or thawing or during unfavorable weather conditions.
(c) Soil Cement Base. This base should consist of a combination of soil and portland cement uniformly mixed, moistened and compacted. Water should be from oil, acids, alkali and vegetable matter and should be reasonably clean. Soil for this base course should consist of the soil found in place, and any additional soil that may be required should be treated as necessary for use as abase material. Prior to mixing, the soil should be pulverized for the full width and sufficient depth of the roadway. The specified quantity of portland cement should be spread in one operation and thoroughly mixed before the application of water and compaction. After compaction, the roadway should be cured for an appropriate period of time and traffic should be prohibited during this time.
(d) Asphaltic Concrete Base. This base should be composed of a combination of course aggregate, fine aggregates and bituminous cement mixed in a central plant. Asphaltic cement to be used in the asphaltic concrete should be uniform in character, free from water and should contain no mineral matter other than that naturally present. Aggregate should consist of fine gravel and sand, disintegrated granite, or other similar granular materials. Where cement concrete or masonry edging is not used, suitable side forms of wood or steel should be placed. Placing of the mixture should be as continuous as possible with all joints well bonded and sealed. After spreading, the mixture should be thoroughly compacted with a power drive roller according to accepted practices. No asphalt material should be laid when the temperature of the air is 50 degrees

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Fahrenheit and falling or during other unfavorable weather conditions.
303-6.1.4 Hard surfaced wearing surfaces, when required, should be of

adequate design for the projected traffic loads. Local regulations, availability of materials, and maintenance facilities will dictate the type of paving to be used. The following types of paving are generally acceptable, although some types may not be locally accepted, or additional materials may be used according to local regulations.


(a) Portland Cement Concrete Pavement. This surface should consist of water, aggregate and cement in the required proportions. Forms should be placed to acceptable tolerances, properly braced, and well oiled before placement of the material. The concrete should be deposited rapidly and leveled according to approved methods. Finishing should be done to remove free water, to provide the desired final appearance and to correct surface irregularities. Expansion and contraction joints should be provided at the required intervals. Properly protected curing for a minimum 72 hours should be observed. No concrete should be placed on a frozen or thawing subgrade or during unfavorable weather conditions, or when the temperature is 38 degrees and falling.
(b) Double Bituminous Surface Treatment (Cutback Asphalt). This surface should consist of three applications of bitumen and a spreading of coarse aggregate and seal coat aggregate on a prepared base. Bituminous materials should conform to applicable specifications. Aggregate should be crushed stone and should consist of particles of clean, hard, tough, durable, uncoated rock fragments and should be reasonably free from an excess of flat, elongated soft or disintegrated pieces, organic or other objectionable matter and should be free from lumps of clay. The bitumen should be applied with a pressure-type power distributor. A prime coat should be uniformly spread and allowed to set up. A second coat should be applied followed immediately by an application of coarse aggregate which should be uniformly rolled. A seal coat of bitumen and aggregate should be applied after all loose and excess aggregate have been removed from the first coating. No materials should be placed when either the temperature of the air or base on which the material is to be placed is 50 degrees Fahrenheit and falling or during unfavorable weather conditions.
(c) One Course Asphaltic Wearing Surface. This surface should consist of a wearing course composed of aggregate and bituminous material mixed in a central plant. Liquid asphalt should be of acceptable quality. Asphalt cement to be used in

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The asphaltic concrete should be uniform in character, free from water and should contain no mineral matter other than that naturally present. Aggregate should consist of fine gravel and sand, disintegrated granite and other similar granular materials. The existing surface should be cleaned before application of the tack coat by a pressure-type power distributor. The bituminous mixture should be spread, raked and rolled in an acceptable manner. Longitudinal and transverse joints should be well bonded and sealed. No asphalt material should be laid when the temperature of the air is 50 degrees Fahrenheit and falling or during unfavorable weather conditions.
(d) Asphaltic Concrete Wearing Surface. This surface should consist of aggregate and bituminous material mixed in a central plant. Asphalt cement to be used in the asphaltic concrete should be uniform in character, free from water and should contain no mineral matter other than that naturally present. Aggregate should consist of fine gravel and sand, Aggregate disintegrated granite or other similar granular materials. The bituminous mixture should be spread, raked and rolled in an acceptable manner. Longitudinal and transverse joints should be well bonded and sealed. No asphalt material should be laid when the temperature of the air is 50 degrees Fahrenheit and falling or during unfavorable weather conditions.
303-6.1.5 All-weather surfaces, where acceptable, should be designed to

accommodate the projected traffic load. The subgrade and base should be constructed in a manner similar to hard-surface roads so that hard surfacing can be easily accomplished at a later date. The following types are generally acceptable and other types may be used dependent upon local conditions.


(a) Layered Oil Surface. This surface should consist of aggregate and waste oil thoroughly mixed and compacted. The base should be scarified and oil applied by a pressure-type power distributor. This process should be repeated a number of times until the mixture is consistent to an acceptable depth. Final compaction should provide a regular surface with the required density.
(b) Gravel Surface. This surface should consist of course and fine aggregates applied in a manner similar to gravel bases. If the gravel wearing surface is for long-term usage, a permanent gravel or crushed stone base should be covered with a layer of aggregate selected or treated to minimize dust in use. Where hard surfacing is anticipated within 24 months, a suitable gravel base may be used as a driving surface provided adequate maintenance is performed and the base is adequately required before application of the hard surfacing.

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303-7 RELATED IMPROVEMENTS
303-7.1 Planting Strips. When provided, should not be less than twelve

(12) inches in width. Plantings at intersections should not interfere with lines of sight necessary for safe driving conditions.


303-7.2 Street Trees. Street trees, of a variety and size in accordance

with the standards adopted by the local governing body, may be planted between street and curb and gutter and sidewalk.


303-7.3 Street Lighting. In addition to the required street

intersection lighting, it may be desirable for a subdivider to install street lights throughout the subdivision. In these cases, a subdivider should conform to the requirements generally in use in the area and payment for electrical power use for the street lighting should be that in common practice in the area. Generally, the public body that accepts maintenance of the streets will provide the power for street lighting.


304 GRADING DESIGN
304-1 GENERAL
304-1.1 Site grading should be designed to establish building floor

elevations and ground surface grades which:


(a) Minimize earth settlement problems.
(b) Avoid concentrating run off onto neighboring properties where erosion or other damage will be caused.
(c) Provide useable outdoor space.
(d) Minimize erosion.
(e) Avoid deep cuts and fills.
(f) Minimize the need for banks, retaining walls or terracing, and avoid long or repeated flights of steps.
304-1.2 Grades should not be designed which direct a concentrated flow

of surface drainage over existing or proposed slopes.


304-1.3 All earth slopes with grades of three on one or steeper should

be planted with appropriate vegetative cover to minimize erosion.


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304-1.4 Occupant and visitor exposure to potential hazards such as rock

slides or steep cliffs, created by existing slopes, should be minimized by the installation of fences, walls or planting, as appropriate.


304-1.5 Maximum gradient for useable open areas should be 5.0 percent.
305 DRAINAGE
305-1 GENERAL
Provisions should be made for the best available routing of runoff water to assure that buildings or other important facilities will not be endangered by the path of major emergency flood runoff which would become active if the capacity of the site storm drainage system is exceeded.

305-2 SWALES AND OPEN DITCHES


305-2.1 In areas provided with open drainage ditches, locations where

these facilities intersect streets should have culverts, riprap and bulkheads adequately sized and constructed to prevent the flow of water across the pavement surfaces and erosion of the roadway base.

305-2.2 Where a swale or drainage ditch intersects a sidewalk or

driveway, an adequately sized culvert or bridge should be provided. Walks should not be designed as drainage ways.


305-3 STORM SEWERS
305-3.1 A storm sewer or swale discharge into ponds, swales or ditches

should have either riprap, headwall, or other similar protection to prevent undermining of the cutlet pipe and erosion of the side slopes.


305-3.2 Consideration should be given to emergency outlets when the

storm sewer system is inoperable due to blockage or when the design capacity has been exceeded.


Headwalls and other appropriate construction should be placed at the open ends of storm sewers to prevent excessive erosion and undermining of conduit.
305-4 SUBSURFACE DRAINAGE
305-4.1 Developed portions of a site which can be adversely affected by

a potentially high ground water table should be drained where possible by subsurface drainage facilities adequate for the disposal of excess ground water.

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305-4.2 Drywells should be placed a minimum distance of 20 ft. from

buildings. This distance may be reduced to 10 ft. if the drywell does not exceed 3 ft. in diameter.

306 THE PROPOSED SITE
306-1 GENERAL
The site design should be arranged to utilize and preserve the favorable features and characteristics of the site and to avoid or minimize the potential harmful effect of unfavorable features.
306-2 TOPOGRAPHY
In the design of a site, the effect of topographic conditions on the costs of development and operation should be considered when locating various uses on the land. Land uses should be combined with site conditions in a manner which assures a functional and economically maintainable development and in a manner which permits correction of potential hazards.
306-2.1 Ground Contours
All elements of the site plan should be designed to fit the natural contour of the land as closely as possible and practicable.
306-2.2 Vegetation
Existing healthy trees, shrubs, and natural cover of good quality which will contribute to the living environment and which can be saved within the site design should be preserved.
306-3 GROUND WATER
Buildings, structures, streets, paved areas and utilities should be located on the site in areas of the least potential ground water hazard.
305-4 LOT LAYOUTS
306-4.1 Corner lots for residential use should have extra width to

permit appropriate building setback from and orientation to both streets.

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306-4.2 The subdividing of the land should be such as to provide each

lot with satisfactory access to an existing public street or highway.


insert diagram


DIAGRAM 10. MAKE SHALLOW LOTS DEEPER AND CORNER LOTS LARGER.


306-4.3 In the absence of local regulations on lot dimensions, the area,

width, depth, shape and orientation and the minimum building setback lines should be appropriate for the location of the site and for the type of development and use contemplated.

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306-4.7 Side lot lines should be substantially at right angles or radial

to street right-of-way lines.


306-4.8 Desirable natural features such as streams or lakes should be

deeded to the local governing body or homeowners association. An easement not less than 10 feet in width should be provided for access to and circulation around any common natural feature.


307 YARDS AND BUILDING SETBACK DISTANCE
307-1 GENERAL
307-1.1 The length and height of each building wall, the location of the

main entrance as it relates to the dwelling and to window walls of nearby dwellings, and the location of windows in all habitable rooms should be considered in establishing yard depth.


307-1.2 Building setback distance from the street should provide for

reasonable privacy and minimize the adverse effects of traffic and other noises, fumes, and headlight glare.


307-2 SIDE AND REAR YARDS
307-2.1 Yard space between exterior building walls and the adjacent lot

line should be measured perpendicular to the lot line opposite the building wall at all points. The minimum distance from the wall to the lot line is determined by:


(a) The height of the wall in stories.
(b) The horizontal length of the wall from corner to corner.
(c) The type of wall
(1) Primary Wall is that wall which contains the principal window(s) in a habitable room except bedrooms and kitchen, and/or the main entrance to the dwelling when it directly faces a primary wall of another dwelling.
(2) Secondary Wall is that wall which contains the windows) of rooms for other than a primary wall as defined above.
(3) Windowless Wall is that wall which contains no windows.
307-2.2 Minimum distance from building wall to lot lines should be:
(a) Primary Wall
6 ft. plus 2 ft. for each story (S) in height plus 1 ft. for each 10 ft. of length (L). D = 2S + L/10

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(b) Secondary Wall

2 ft. + 1 ft. for each story (S) in height plus 1 ft. for each 10 ft. of length (L), minimum distance 5 ft. D = 2 + S + L/10.


(c) Windowless Wall

Yard depth for walls containing no windows, or only windows which do not involve loss of privacy for required interior space should be no less that 8 feet.


(d) Retaining Wall

The distance between a building wall with habitable room windows and a retaining wall with the top above the midpoint of the vertical height of the lowest window should be a minimum of the appropriate primary or secondary wall distance, see above, treating the retaining wall as a lot line.


307-3 DISTANCE BETWEEN BUILDINGS
307-3.1 The distance between buildings should not be less than the sum

of the yards of the individual wall types recommended by section 307-2.2.


307-3.2 Where a window wall is opposite a windowless wall, the distance

between buildings is determined by the required yard space for the window wall.


307-3.3 Where opposing walls have no windows, there is no required

distance between buildings other than for fire protection.


307-4 BUILDING STREET SETBACK DISTANCE
307-4.1 The setback distance of buildings from the front property line

and the street side lot line of corner properties should:


(a) Be diversified to assure visible variety in building and space relationship avoiding monotony.
(b) Be consistent with the best building placement considering the topography and other site conditions.
(c) Provide space for facilities for necessary functions such as walks, drives, parking space and plant materials.
(d) Be adequate to assure reasonable visual and auditory privacy for indoor and outdoor living areas.
(e) Minimize adverse effects of fumes, headlight glare, and other nuisances.

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307-4.2 Buildings should be set back from parking areas and screened to

minimize headlight glare into habitable rooms and should be arranged to prevent direct or concentrated discharge of automobile exhausts into any window.


308 PARKING AREAS
308-1 GENERAL
Adequate parking space should be provided for residents, guests and, where appropriate, service vehicles. Where practical, additional parking space should be planned and reserved for future use.
308-2 NUMBER OF SPACES
308-2.1 The number of parking spaces to be provided should be based on

individual analysis of each housing proposal.


308-2.2 Detached single family housing should have one parking space per

unit on each lot. This space should have an all-weather surface and minimum dimensions of 10 feet by 22 feet.


308-2.3 Off-site parking spaces for multi-family housing may be

substituted for onsite parking, if available, and acceptable to the local authorities.


308-3 PARKING BAYS
Parking bays for multi-family projects and townhouses should meet the following:
308-3.1 Minimum single space dimension should be 8 ft. wide and 18 ft. Deep. Maximum number of spaces in a single bay should be 20. Minimum distance between bays should be 8 ft.
308-3.2 Maximum walking distance from a parking space to a public

entrance of apartment building served should be:


(a) Non-elderly resident parking space - 250 ft.
(b) Elderly resident parking space - 150 ft.
(c) Guest parking space - 300 ft.
308-3.3 Wheel stops or other appropriate barriers should be provided and

suitably placed to prevent unwanted vehicular encroachment beyond parking area limits.

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309 WALKS
309-1 GENERAL
Walks should be provided for safe convenient access to all

dwellings and for safe pedestrian circulation throughout a development between facilities and locations where major need for pedestrian access can be anticipated.


309-2 PUBLIC OR COMMON USE WALKS
309-2. 1 Where the window sill of a bathroom or bedroom is less than 6

ft. Above a public walk, the walk should be at least 8 ft. from the wall containing the window.


309-2.2 Minimum walk width should be 4 ft. except abutting a parking bay

or court where it should be 6 ft. to accommodate car overhangs and provide walking space.


309-2.3 Sidewalks at least 5 feet in width should be provided on each

side of all arterial streets or designated state roads where necessary for pedestrian and traffic safety. Sidewalks at least 4 feet in width should be placed along marginal access streets where necessary for pedestrian and traffic safety.


309-3 ENTRANCE WALKS
309-3.1 Minimum walk widths should be:
(a) Principal walk (serving more than one unit) 4 ft.
(b) Minor walk (serving only one unit) 3 ft.
(c) One & two family dwelling entrance walk 3 ft.
(d) Elevator building entrance walk 5 ft.
309-4 CHEEK-WALKS
Cheek-walls should be provided at least 4 in. thick for step flights of three or more risers except where the rear intersection of treads and risers are at least 2 in. above grade.
310 SERVICES
310-1 GENERAL
Necessary services supplied by the local community should be provided the required space and accommodation in the site design to permit economical operation and maintenance.

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310-2 ACCESS
Direct and convenient site access should be provided for all

deliveries and services including furniture moving vans, fuel trucks, refuse collections, utility meter readings, mail deliveries, fire fighting equipment and ambulances.


310-3 GARBAGE & REFUSE
310-3.1 Single family housing should have space adjacent to each living

unit for refuse can storage.


310-3.2 Multiple family housing projects should have an outdoor facility

for garbage and refuse collection and disposal which can be maintained in a sanitary, sightly condition where other provisions have not been made. Collection stations should be designed with easily cleaned, nondusting or paved surfaces.


310-4 SERVICE SCREENING
Service areas and facilities should be screened.
311 PLANTING DESIGN
311-1 GENERAL
Planting design should coordinate appropriate new plant

materials and their ecological requirements with the climate, soil, orientation, water courses, existing vegetation, related natural resources and manmade facilities. A variety of plant materials should be provided to enhance the appearance of buildings and grounds, provide necessary screening, help separate incompatible use areas, arrest erosion and reduce noise.


311-2 LAWNS
Lawn preparation should include a surface layer having a minimum depth of 4 in. comprised of surface soil with a known local capability of satisfactorily supporting lawn growth.
312 SITE DETAILS
312-1 GENERAL
Elements of the site such as shelters, service structures, walls, fences, planting tubs and boxes, benches, patios recreational equipment and paved areas should be furnished according to occupant needs and local customs.
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312-2 LAUNDRY DRYING YARDS
Laundry drying space should be provided in suitable areas and located away from public view where other laundry drying facilities are not furnished.
312-3 WALLS AND FENCES
312-3.1 Walls and fences should be included in the site design as

appropriate to provide safety, screening, noise reduction or grade transition.


312-3.2 Guardrails or other suitable barriers should be provided on

accessible retaining walls or at other locations which, because of the height (24 in. or over) or other factors, constitute a hazard to life safety.


312-4 OUTDOOR LIGHTING
All public areas where pedestrian use can be anticipated after sunset should be adequately lighted for security purposes where arrangements for permanent maintenance and operation can be assured.
313 COMMON USE FACILITIES
313-1 GENERAL
Improved open space for both active and passive recreation should be provided. The improvement should be consistent with the size of the development, age levels, and needs of intended occupants and should consider operation and maintenance costs.
312-2 RECREATION
312.2.1 Adequate recreation space appropriately equipped should be

provided, consisting of open areas for active recreation such as playground or major sports, and places for passive recreation such as parks and sitting areas.

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312.2.2 Publicly owned and maintained parks, playgrounds and school

grounds which are convenient to a development and readily available for use by the residents may be considered in the design of the site.
312.2.3 Recreation areas for the elderly should be separated from areas

designed for use by children or young adults in projects accommodating both elderly and families.


314 HILLSIDE DEVELOPMENT

314-1 GENERAL


It is the intent of this Section to provide guidelines for sites, where the majority of the land area has slopes exceeding fifteen percent (15%) and special measures must be taken to provide adequate building sites with safe access and reliable utilities. These steep sites will be acceptable for Rural Development financed housing only if the State Director determines there are no other suitable sites of lesser slopes available in the area where the housing need exists.
314-2 MANUFACTURED SLOPES
314-2.1 All manufactured slopes adjacent to the roadway should normally

be a maximum of two horizontal to one vertical (2:1 unless limited to existing topography or constructed in rock. Manufactured slopes of less than two to one (2:1) may be permitted where adequate slope control measures such as retaining walls or rip-rap embankment are utilized. The slope should in no case exceed the natural angle of repose of the material. Cut and fill slopes should be constructed to eliminate sharp angles of intersection with the existing terrain and should be rounded and contoured as necessary to blend with the natural topography to the maximum possible intent.


314-2.2 All manufactured slopes, other than those constructed in rock,

should be planted or otherwise protected from the effects of storm erosion as soon as possible after construction and should be benched, terraced and excessive runoff diverted as required to provide for adequate stability. If the severity of the slope or the composition of the soil indicates unusual stability hazards, according to soil reports, further remedies may be necessary as determined with the assistance of a qualified soils engineer.


314-3 LOT AREAS
As the slope of terrain increases, lot areas normally increase to provide adequate outdoor living area, driveways, allowance for slope maintenance, snow removal or collection, etc. Lots should be of adequate size to meet the needs of occupants of the structure to be placed thereon.

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314-4 LOT WIDTH
The lot width should be sufficient to provide an acceptable building site and reasonable and safe access.
314-5 WALKWAYS
Walkways should be provided when dwelling units have frontage on major streets and highways, or when considered necessary to provide pedestrian safety along public streets. Slip resistant stepping stones or other durable materials may be substituted for paved walks. Walkways should preserve the character of the hilly area to the maximum extent possible.

314-6 STREET CONSTRUCTION


Streets constructed on a gradient in excess of 18% should consist of a portland cement concrete surfacing with a minimum thickness of 6 inches placed on a suitable base course and should be provided with a roughened surface to minimize skidding or slipping of vehicles.
314-7 DRIVEWAYS
Driveways should be designed to a grade and alignment that will provide the maximum safety and transition to prevent "bottoming out" in a manner which will not interfere with drainage or public use of the street and/or street area.
314-8 LIGHTING
Where considered necessary for safety purposes and where permanent maintenance and operation can be assured, outdoor lighting and/or street lighting should be provided.

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