- - AGRICULTURE CORE CURRICULUM - - (CLF6000) Advanced Core Cluster: ORNAMENTAL HORTICULTURE (CLF6700) Unit Title: LANDSCAPE DESIGN, CONSTRUCTION, AND MAINTENANCE ____________________________________________________________________________ (CLF6702) Topic: HARDSCAPE OPTIONS AND DESIGN Time Year(s) 4 hours 3 / 4 ____________________________________________________________________________ Topic Objectives: Upon completion of this lesson, the student will be able to: Learning Outcome #: - Demonstrate an understanding of the various structural elements in the landscape and the options for their use as they relate to the following: (M-2) - Prepare a simple landscape design. (M-3) - Prepare a landscape plot from a plan layout. Special Materials and Equipment: Drawing vellum or sketch pads with 1/4" grid, drawing supplies, and architect's scales. References: Cotton, Lin. (1985). ALL ABOUT LANDSCAPING. Available from: Ortho Books, P.O. Box 5047, San Ramon, CA 94583. Hannebaum, Leroy. (1981). LANDSCAPE DESIGN: A PRACTICAL APPROACH. Reston, VA: Reston Publishing Company. Ingels, Jack E. (1987). LANDSCAPING (3rd ed.). Albany, NY: Delmar Publishers. Landphair, H. C., & Klatt, F., Jr. (1979). LANDSCAPE ARCHITECTURE CONSTRUCTION. New York: Elsevier Science Publishing Company. Editors of Sunset Books and Sunset Magazine. (1984). LANDSCAPING ILLUSTRATED. Menlo Park, CA: Lane Publishing Co. Editors of Sunset Books and Sunset Magazine. (1988). WESTERN GARDEN BOOK. Menlo Park, CA: Lane Publishing Co. Wilson, Scott. (1976). LANDSCAPE CONSTRUCTION. San Luis Obispo, CA: California Polytechnic State University, Vocational Education Productions. Evaluation: Unit Exam ===================================================================== *** INSTRUCTORS PLEASE NOTE *** The detail of this topic presentation goes beyond the scope necessary to meet the requirements of the Core Cluster in this area. It will take longer to teach than indicated above if covered entirely. It is included for local enrichment as appropriate to the class. ===================================================================== TOPIC PRESENTATION: HARDSCAPE OPTIONS AND DESIGN A. Hardscape Elements in the Landscape: The "hardscape" portions of a landscape are the parts that are constructed, sometimes called the structural elements. These structural elements range from "backbone" items such as retainers and sub-grade support structures to the "finishing touches" of a landscape such as a gazebo, paving or fountain. They are just as important, if not more so, as the plant material planned for the landscape. 1. Cost: The structural elements usually represent the main cost of installing a landscape. Plants are, by comparison, relatively inexpensive, and easy to install. 2. Coordination: Careful planning and coordination are required to install the hardscape. Structural elements, once installed, can be difficult to work around (or under) so must be constructed in an order allowing for subsequent work. 3. Aesthetic Quality: The hardscape sets the aesthetic tone of the landscape. The structural elements should be planned to harmonize with each other AND the plant material, to give the total effect desired. B. Hardscape Options: In designing the structural elements of a landscape there are many choices to be made. Some elements, such as retaining walls and paving must be installed for practical reasons, depending on the lay of the land and the basic requirements for the site. Other constructed elements, such as pools and overhead structures, are optional, depending on the aesthetic choices of the designer and the budget. In either case, there is a wide variety of materials and styles for building structural elements, giving the landscape designer many options in constructing the hardscape. Described below are the kinds of structural elements found in most typical residential and commercial landscapes. In addition to guidelines for their use in the landscape, some of the options for materials used in their construction are listed. 1. Patio Paving: The patio extends the living, dining, and entertaining area of a building into the landscape. a. Patio paving should be simple, not a mixture of too many different styles or materials. The materials chosen should harmonize with nearby architecture and plantings. b. A relatively even, smooth surface should be the result, especially if there will be a lot of foot traffic or entertainment on the patio. c. Choose materials which are abundant locally. Heavy paving materials are expensive to ship long distances. d. Plan well for drainage. Most paving materials don't drain through, so the patio should be graded slightly to areas which drain. Large patios will require installed drainage. e. Materials: Choosing a paving material is a matter of balancing aesthetic appeal, cost, ease of installation, durability, and safety factors. 1) Poured Concrete: a) Concrete can be poured in any shape and can be finished in a number of textures, including exposed aggregate. b) Concrete is extremely durable and is low in cost. c) Careful site preparation is required for concrete. 2) Concrete Pavers: a) These standardized units come in many shapes including square, rectangular, and interlocking. b) They are easy to install on a flat prepared surface (mortar or sand can be used), and come in a variety of colors and textures. 3) Brick: a) Brick is a classic paving material and can give either a formal or informal feel, depending the brick chosen and the method of installation. b) Brick comes in many colors, textures, and sizes, and provides a sure footing. c) Brick is moderately expensive to buy and is time consuming to install. d) Unlike concrete, brick can be installed in stages if necessary. e) Brick can be laid in a number of different patterns (called "bonds") to add interest to the paving. 4) Stone: a) Stone such as flagstone and slate give a natural look which is highly desirable in some landscapes. b) Stone is a high-cost item, and requires time and skill to install properly. c) Weight and a surface that can be slippery when wet are other disadvantages. 5) Tile: a) Terra-cotta or finished-looking "fired" tile lend a more formal appearance to a patio. b) Tile is expensive and should be installed with care for the finished effect it suggests. c) Some tile can be slippery. d) Consider planning tile project dimensions to evenly fit full-size units; tile is difficult to cut. 6) Wood: a) For an informal, low-cost paving material, wood can be installed in blocks, rounds, or ties. b) Wood is not a durable paving material and will have to be replaced as it decays. 2. Walkways: Walkways, like patios, combine function and aesthetic appeal. The walkway should lead people along a natural route from one place of interest in the landscape to another. Safety, and harmony with other landscape elements, especially other paving elements, are important as well. a. The route should feel comfortable and natural. While straight lines represent the shortest distance between two points, their use in landscapes should be restricted to formal designs. b. The size of the path should be determined by the number of people or kinds of equipment that will need to use the pathway. The minimum width for a path is between two and three feet. Main walkways should be wider. c. Proportion of the path in relation to surrounding landscape features is important: A too-wide path in a small landscaped space looks out of place. d. Materials: Materials for walkways are similar to the materials used for paving, described above, but there are some special considerations: 1) Avoid using glazed or uneven materials for walkways. 2) Materials should be chosen to take the wear and tear they are likely to receive. This can increase the requirements for preparation of the sub-grade before installing surface materials. 3. Steps: Steps are more than just an extension of a walkway. They transition between "outdoor rooms" in the landscape, and set the tone for different landscape areas. a. A building permit will be required if steps are being installed in a public area or directly adjacent to a public area. b. The flat part of the step is called the tread. The tread should be a minimum of eleven inches in depth; fifteen inches is more comfortable. c. The vertical part of a step is called the riser. A riser should be between four and eight inches in height. d. All risers and treads in a set of steps should be uniform in size. e. If slopes are too steep, curve the steps or cut across the slope to decrease the pitch. A switchback with a landing is sometimes necessary. f. Materials: Again, materials for steps can be chosen from the same options as for patios and walkways. Steps should harmonize with other paving materials. 1) In choosing materials, put safety FIRST. Avoid slippery or uneven material. 2) Steps provide an opportunity to transition between types of paving by combining the different materials in the steps. 4. Edgings: Edgings define different landscape features, especially turf, groundcovers, and pavings. They serve functional purposes and add to the visual impact of the landscape. a. Edgings can be set flush to the grade or can rise up above the ground for a special effect. If edgings are to take traffic, they must be constructed with strong footings underneath. b. In terms of function, edgings can serve to retain loose materials such as soil and gravel. Header-boards along a bed of perennials or shrubs are used for this purpose. c. Edgings make the job of maintaining the landscape easier. Mowstrips are a good example of this function, making lawns easier to mow and edge. d. Edgings add an accent to various landscape elements, setting off and providing contrast with various ground coverings. e. Edgings add a degree of formality to landscaped areas. f. Materials: A crisp, sharp edge is is desirable in edging materials. 1) Brick: These can be set in concrete, on a sand bed, or directly in firm soil. 2) Wood: Wood is an easily-installed and inexpensive edging. a) Rot-resistant or pressure-treated wood can be used for edgings. b) Common dimensions are 2x4 lumber, doubled or tripled 1x4s or multiple layers of bender board for curved edges. c) Railroad ties are rot resistant, easy to install, and sturdy. They lend an informal effect to the edging. 3) Poured Concrete: This makes a strong sub-grade footing for other edging materials, and can be poured in any shape to provide a sturdy mowstrip. 5. Retaining Walls: Retaining walls are necessary on sloped sites to provide level areas for the landscape. They hold back a tremendous weight of soil, and must be carefully designed and constructed. a. In deciding where to place the retaining wall, try to disturb the natural soil as little as possible. b. The retaining wall and footing must rest on sturdy, undisturbed soil. c. Providing for drainage is critical. Water seeping down through the soil behind the wall must be allowed to drain away from the wall through a drainage pipe, or to move through to the front and drain away. If this is not done, the extra weight of the water could cause the wall to fail. d. Any wall over three feet in height should be designed and installed by a professional, with approval from a licensed engineer. e. Low, informal walls can be composed of loose materials. Higher walls MUST be constructed on a solid concrete footing and securely fastened. f. Materials: While functional considerations are paramount, retaining walls can beautify a site if materials are carefully chosen and installed. 1) Wood: a) Wood is best used for shorter walls. b) Wood is easy to handle and work with and gives a natural appearance. c) Rot-resistant types of wood or pressure-treated lumber is necessary, since the retainer is in constant contact with the soil. 2) Uncut Stone: a) Stone can be set in mortar for strength, or loosely set for a low, informal, combination rock- garden/retaining wall. b) Uncut stone gives a natural, attractive look to the landscape. c) Stone can be expensive and is heavy to handle. 3) Broken Concrete: a) The "poor man's stone," broken concrete is a fairly attractive alternative for informal retaining walls. b) Try to obtain concrete of uniform thickness for appearance and stability. 4) Masonry Blocks: a) Cinder blocks, appropriately reinforced, make sturdy retaining walls. b) The aesthetic appeal of such walls is limited. Usually these are faced with more attractive materials such as brick. c) Brick alone is suitable only for small retaining walls unless substantially reinforced. 5) Poured Concrete: a) Concrete walls are used when strength is the greatest concern. They should be professionally installed. b) The concrete surface can be textured to add interest and soften harsh flat surfaces. 6. Garden Walls: Garden walls serve to provide privacy, screen out unsightly views, noise and wind, and add to the security around the landscape. Fences, of course, do many of the same things, but without the sense of stability and permanence that walls provide. a. Walls are expensive to construct. The materials are heavy and great care and skill are required in their installation. b. All garden walls require a solid footing, twice the width of the wall itself, and as deep as the wall is wide. c. Walls over three feet in height should be engineered and built under permit. d. Aesthetically, a garden wall makes a very strong statement. Be careful that the tone of the wall matches that of the landscape in general. e. Materials: Garden walls are constructed out of masonry, which can be stone, concrete, or brick. 1) Stone walls give a natural and "established" look to the landscape; however, they take a long time to construct due to the irregularities in shapes and sizes of the stone. 2) Bricks, blocks, and adobe offer less expense and greater ease of construction than stone. The smaller the units, the more important it is to reinforce the wall with steel reinforcing bar. 3) Poured concrete is the strongest option, but it has little visual appeal. 7. Fences and Gates: Fences provide security, define legal boundaries, and screen out undesirable noise, wind, and views; they can also separate "outdoor rooms." a. According to most municipal codes, fences should be no more than 42 inches high in a front yard, or 72 inches high in a back yard. However, codes vary from community to community, so check the local ordinances. b. Fences can follow the contour of a slope, or can be constructed in stepped panels for a more formal, terraced effect. c. The two basic styles of fencing are open and solid. 1) Open-style fences, such as picket and split-rail fences, are more for setting an aesthetic tone and marking boundaries, than functioning to preserve privacy or to provide screening. 2) Solid-style fences, such as board-and-batten and clapboard fences, keep out undesirable views, dust, wind, and noise. 3) Fencing style should be chosen considering both aesthetic and functional needs. d. Most fences are constructed of three parts: 1) Posts: These are placed in the ground to provide support for the fence, and can be made of 4x4 timbers, peeler cores, or in a formal landscape, masonry structures. Posts must be rot-resistant where they contact the soil. 2) Rails: Also called stringers, these connect the posts and provide horizontal support. They are usually made of 2x4 lumber. 3) Siding is the main part of the fence, affixed to the rails. Siding should be chosen in accordance with the general landscape style. 4) Caps and special baseboards are optional for more formal-looking fences. e. Make sure gates are wide enough to accommodate gardening or recreational equipment that needs to pass through into the yard. f. Materials: Fences are usually made of wood. A very wide variety of materials are available for fence construction. Siding options include: 1) Redwood Planks: Fast to construct and inexpensive. 2) Grape Stakes: Give a rustic feel. 3) Split Rails: For a Western look. 4) Clapboard: Yields a formal, private appearance. 5) Lattice: Open and airy. 6) Chain link: For security and utility purposes only. 8. Decks: Decks serve the same purpose as a patio, but offer more versatility with regard to their location. a. Decks can be built anywhere from just-above-grade for a "floating" effect, to high on posts off a second-story bedroom. b. Decks can make otherwise unusable area (too steep or hilly) into an outdoor living space useful for leisure or entertaining. c. Decks can be attached to homes or buildings, or they can be built as free-standing structures. e. While finished deck design and shape is limited only by the designer's imagination, most decks have the same underlying construction. There are five layers of materials for most decks: 1) Piers: These are concrete blocks set on the ground or poured in place to provide a solid footing for posts to rest on. They are often set on larger concrete footings poured below grade. 2) Posts: Cut from 4x4 timbers for average-height decks, posts are cut to varying lengths to account for differences in the grade below the deck. This way, a level deck can be built on a sloped surface. 3) Beams: Constructed from 4x6 timber, or sometimes deeper 4x8 material, beams rest on posts and provide support for the joists. 4) Joists: These rest on, and run perpendicular to, the beams. Joists are closely set (usually 24 to 32 inches apart) to provide a firm underpinning for the decking. Joists are made of dimension lumber, usually 2x8s. 5) Decking: This is the material that is seen and walked on. Decking is usually cut from clear (or almost knot- free) redwood, and it routinely comes in a 2x6 size. f. Materials: Decks are built primarily out of redwood lumber or other rot-resistant wood such as cedar or cypress. 1) Support structure can be constructed out of less visually appealing materials such as pressure treated Douglas fir. 2) While most quality decking materials age gracefully, a protective water sealant or finish will extend the life of a deck and can improve its appearance. 9. Screens: Screens function much like fences, but are lighter in feel and construction. a. They are used to define different parts of the landscape, and establish "outdoor rooms." b. Screens are used to filter out wind, noise, or undesirable views. c. Screens are usually decorative in nature, and are useful for lending a formal or rustic feel to an area. d. Materials for screens are many and varied: 1) Use decay-resistant materials for posts and stringers. 2) Potential screening materials include lath, reeds, glass, translucent fiberglass, canvas, and lattice panels. Copper pipes, allowed to weather and turn green, make a unique screen. 10. Overhead Structures: These serve to provide shade, either filtered or full, and can provide an outdoor space protected from rain. a. Overhead structures can be constructed with a solid roof or an open one, depending on the purpose of the structure. b. A freestanding structure can be built for enjoyment of the landscape, or an overhead structure can be attached to a house or building. c. To avoid a cramped feeling, an overhead structure should be at least eight feet high. d. While joist hangars, tie strips, and other metal connectors are handy for general construction, their use for open structures such as overheads in the landscape create an unfinished look. Use more traditional joinery methods instead. e. Plants such as vines can be trained up an arbor to provide filtered shade and show off the attributes of the vine. f. Materials: Similar to fences and screens. 1) Redwood or other rot-resistant materials are preferred materials for post and beam structural work. 2) Roofing materials vary from evenly spaced 2x6s to glass panels or canvas. 3) Again, match the material to the overall "feel" of the landscape, whether it is formal, rustic, or innovative. 11. Gazebos and Enclosures: Outdoor rooms add value and additional usefulness to the landscape. Their specific purposes are many and varied, as are the possible styles. a. Outbuildings and enclosures are usually elaborate projects that must meet local code requirements and be built under permit. b. The style of the building can conform to the basic themes of the overall landscape, or might provide a counterpoint or accent by making a different design statement. (Only one structure should be used this way, or a confused appearance will result from competing styles.) c. There are many types of structures that can add to the landscape. Some ideas follow: 1) Traditional Gazebo: A comfortable place to enjoy the surrounding landscape which also serves as a decorative focal point of its own. 2) Pool Pavilion: For changing clothes and relaxing around a swimming pool or spa. 3) Enclosed Patio: Can be attached to the house, or made freestanding. For recreation or entertaining while retaining an outdoor feel. 4) Greenhouse: For growing plants for the garden or as a hobby. Again, can be freestanding or attached to another structure. d. Materials: Materials vary with the purpose and style of the building. 1) Most are constructed from weather-resistant wood such as redwood. 2) Natural wood finishes can be stained or are attractive left to develop a natural weathered look. 3) Many outdoor structures are painted to provide contrast in the landscape. 12. Water Features: Whether for recreation, a visual enhancement, or simply to provide a soothing background sound, water can enhance enjoyment of the landscape as much as any other amenity. a. Larger water features require permits to install, and should usually be handled by professionals. b. Common concerns for all types of water features include access to drainage, safety, and maintenance of water quality. These should all be considered in the planning process. c. Siting a water feature is critical. 1) Many water features have special requirements with regard to sun or shade, wind protection, physical and visual access to the rest of the landscape, and privacy. 2) Water features, depending on their size and style, can dominate the landscape visually. Locate the water feature so the desired effect is attained. d. There are water features for many purposes, each having their own special requirements. Some of the main types include: 1) Garden Pools: These can be constructed for a variety of purposes: small or large; for plants and fish or just for the cooling presence of water; with a soothing fountain or waterfall, or a quiet pond for water lilies. 2) Fountains: Fountains contribute the pleasing sound of falling water, which can be particularly welcome if there is background noise near the landscape such as a freeway. 3) Swimming Pools: In most landscapes, a swimming pool will become the central design feature in the landscape. Siting and designing the pool will affect the entire project. 4) Hot Tubs and Spas: Privacy, utilities, drainage, and access to the home or changing facilities are things to keep in mind when designing a hot tub or spa into the landscape. e. Construction methods are beyond the scope of this lesson, but some design questions to consider include: 1) Will the pool/spa/tub/fountain be installed below grade or above grade? Below-grade water features are usually more difficult to install, but integrate visually into the landscape more easily. 2) Can pre-fabricated units be installed? This reduces cost considerably. 3) Is the area secure or securable? Many communities require that water features be fenced off from access to children. f. Materials: 1) Traditionally, concrete and plaster have been used for pool construction. Concrete is impermeable and lasts a long time. It is expensive to install. 2) For smaller water features, masonry units can be used, but they must be waterproofed carefully to prevent seepage. 3) Fiberglass and acrylic products, either pre-formed or molded in place, are becoming more popular for their low cost and ease of installation. 13. Landscape Lighting: a. Lighting adds security and safety to the landscape in darkness, making it accessible to users, and less attractive to trespassers. b. From a design standpoint, lighting adds a completely new dimension to the landscape. It enables the designer to control what is seen, and how it is viewed, in the landscape at night. c. By manipulating light and shadow, subtle and striking effects can be created in the landscape for enjoyment at night. Different kinds of lighting effects include: 1) Backlighting: This creates silhouettes, accenting striking forms of structures and plant material. 2) Downlighting: The light source is above the subject, as with natural light. It is most like daylight. 3) Uplighting: This technique illuminates foliage, and can be combined with downlighting for striking light and shadow effects. 4) Accent lighting: This can be used to draw attention to special features in the landscape. 5) Diffused lighting: A soft, even light, creating fewer harsh shadows, can be created by filtering light through a translucent material such as a fiberglass or acrylic panel. d. Lighting can be provided on 12 volt or 120 volt circuits: 1) 12 volt lighting is easy to install, and is very flexible for creating special decorative effects in the garden. 2) 120 volt lighting is necessary where bright illumination is required (as for security lamps or floodlights) and usually requires a permit to install. C. Design Considerations: 1. Simplicity: Avoid filling the landscape with a clutter of structural elements: a. Design in structures that are necessary for adequate privacy, circulation, protection from the elements, and soil retention. b. Additional hardscape features to define spaces, create mood, and provide for recreation and leisure should be used judiciously. 2. Unity: The hardscape elements should articulate functionally, and set a particular tone for the landscape. a. The structural elements should be selected and installed so they work together in the landscape, both visually and functionally. b. Disparate hardscape features, installed in a haphazard manner, will erase any hope of the landscape developing a unified, harmonious feel, no matter how beautiful the plantings might be. 3. Proportion: Keep the various built elements in the landscape in proportion to one another: a. A too-large gazebo or fountain can make an otherwise pleasing landscape feel uncomfortable or cramped. b. While proportion is important, remember the human scale. People must be able to move around in the landscape in a natural manner. __________________________________________________________ ACTIVITY: 1. Have students survey hardscape features around the school grounds and identify their purpose in terms of function (e.g., retaining structure, paving structure, provision for recreation, etc.); also identify the role each plays in the overall landscape design (what kind of tone the elements set, how features contribute aesthetically, etc.). __________________________________________________________ __________________________________________________________ ACTIVITY: 1. Have students, given a base plan of a residence, diagram the hardscape design for a landscape. Each student's plan should include paving such as a patio, walkways, a retaining structure, a water feature, edgings, fencing, and a deck. An outdoor room such as a gazebo or greenhouse is optional, to be included if the student thinks it will fit in well with his or her design. (Several ideas for base plans can be found in Ingels' LANDSCAPING text, page 101.) __________________________________________________________ 1/7/91 MH/clh #%&C