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INTRODUCTION In addition to contributing to the overall design concept as discussed in Section 1, details also resolve aesthetic problems of connection or transition between two or more materials or architectural elements. The shape and character of interior space is determined by many individual architectural elements, including things such as walls, ceilings, floors and free-standing components like furniture and accessories. Even more amorphous characteristics, like light, views, and acoustics can shape the character of an interior space. The fixed, architectural elements either connect with each other or form part of a larger architectural element. The way in which elements connect or transition from one to another is an important part of the overall design and aesthetic impact of a space. If done well, the connection contributes to the function and design impact of a space. If done poorly, the space appears disjointed and badly designed. Sometimes the problem is more a technical one of how to physically make the connection and solve functional problems without being detrimental to the intended design concept. Other times the problem is more an aesthetic one of deciding how to change from one material to another or how to change from one architectural element to another out of a vast range of possible choices. Usually, the problem is a combination of both technical and aesthetic questions; a left brain and right brain solution is required. The best details solve technical problems in the most functional, economical way while elegantly enhancing the design of the project. Detailing questions of connection or transition generally fall into two broad categories: those that occur when interior architectural elements connect, either in the same plane or in different planes, and those that occur when elements are placed on or are a part of other elements. This section discusses ways to make the transition of walls to either the ceiling plane or the floor plane. --- Wall-to- floor transition concepts: component bases; featured bases; standard bases ---- Standard wall-to- floor connections: (a) none; (b) applied; (c) flush; (d) recessed A plain, flat wall with no base presents a clean, contemporary appearance. However, many finishes won’t withstand normal wear and cleaning. In addition, any irregular floor surface or slope must be taken into account when deciding on the wall material and how the bottom edge of the wall will be detailed. An applied base is the most common and works with any base material including wood, vinyl, rubber, stone, metal, and laminated products. This type of base can cover the joint between the bottom edge of the wall material and the floor and in most cases, can accommodate out of level floors. Flush bases combine the advantages of a clean, contemporary appearance with the retention of the functional requirements of a durable base that can withstand cleaning and other abuse. The size of the reveal can be very small to minimize the appearance of the base or can be larger to highlight the separation or make it easier to construct. To minimize the visual impact of the base it can be the same color and texture as the wall finish. A recessed base emphasizes the partition surface as a separate plane from the floor surface. It’s a contemporary look and can mask minor damage to the base material in the reveal. However, it’s more difficult and expensive to construct, generally requiring an additional layer of gypsum wallboard or a second, furred wall. CONNECTIONS OF MAJOR ELEMENTS Interior space is created by combining many individual elements that de fine space and give it a particular character. Floor, wall, and ceiling planes are the obvious major architectural elements that de fine space, but other elements, such as columns, beams, pilasters, dropped ceilings, recesses, and projections, can also be used to shape the quality of space. Technically, there are generally only a few ways to connect major elements so that the functional and constructability needs are satisfied within the given constraints. However, there are often hundreds of ways to make the same connection from a strictly aesthetic standpoint. How these elements connect is a detailing problem. While there are innumerable ways of connecting elements, they all tend to fall into one of the general types discussed in this section. WALL TO FLOOR Wall-to- floor connections are one of the most basic types, and usually little design attention is given to the junction. The floor supports the load of the partition, and generally each plane is finished with different materials with the joint between the two planes covered with some type of trim. Some of the general types of wall-to- floor connections. Which detailing approach is used depends on whether the designer wants to give equal weight to both the floor and partition or whether the goal is to visually separate the two planes. Each produces a unique design effect useful for different design goals. E.g., continuing the flooring material partially up the wall increases the apparent area of the floor. The types of transitions can be grouped into three general categories: standard bases, featured bases, and component bases. Standard Bases NO BASE In the most basic form, the partition simply rests directly on the floor with no trim. The effect is plain, stark, and contemporary and may be appropriate in some situations. For practical reasons of construction and maintenance, a durable base should be provided, but this can be done by detailing the base flush with the partition surface and finishing it with the same color and texture as the wall. If the partition finish is durable itself, it may be extended to the floor. How the bottom edge of the wall material is finished depends on the type of flooring. E.g., if the floor will be carpeted, gypsum wallboard can be carried to the floor with a slight gap as is normal for wallboard installation. Carpet and pad would then cover the gap. For a hard-surfaced floor, such as wood or resilient tile, the bottom edge of gypsum wallboard would need to be finished with a standard wallboard L-trim or J-trim. Alternately, an aluminum reveal trim similar to that can be used. Generally, omitting a base is not advisable, especially where frequent cleaning of the floor is required. This base treatment is difficult to use when the floors are not level because each piece of wallboard or other wall finish must be cut to fit the floor line. APPLIED BASE --- shows the standard method of treating a wall-to- floor detail with a piece of applied base. The base covers the joint, while providing protection from cleaning equipment and kicking. This approach is inexpensive and easy to construct, while providing a wide choice of sizes, and con figurations, and base materials, including resilient materials, wood, stone, or metal. Applied bases are fairly easy to remove and replace for remodeling or recycling. FLUSH Flush bases, provide the functional requirements of protection and joint concealment, while minimizing the visual impact of the base and giving a more contemporary appearance than an applied base. The base may be a contrasting material and color or one that matches the wall finish. As with any detail involving more than one material, it’s difficult to construct a perfectly flush joint in the field, especially when one of the materials is gypsum wallboard. Three ways to create a flush base are shown. To accommodate unleveled floors, the designer must decide whether to have the base and trim follow the line of the floor, scribe the base to fit the line of the floor, or have the trim set level and allow the reveal to vary in size as the base follows the floor line. --- Flush base details: (a) double layer wallboard (b) aluminum base trim (c) reveal trim L- or J-trim set level wood or plastic laminate on particleboard wood or plastic laminate on particleboard scribe to floor carpet or hard surface floor aluminum base trim line follows line of floor aluminum reveal trim set level base scribed to floor or minor gaps allowed -- RECESSED A recessed base emphasizes the separation between the ground plane and the wall plane. One of the practical advantages of a recessed base is that minor damage or soiling from cleaning operations is not as noticeable as with a flush or applied base. However, in most cases, a flush base requires a double-layer application of wallboard, especially if the partition requires a fire rating or if acoustical separation is needed. Several of the ways to detail a recessed base. The simplest method uses a second layer of gypsum wallboard stopped short of the floor and trimmed with standard J-trim or L-trim. A base thinner than the thickness of the wallboard is used to finish the recessed portion. The wallboard trim can be set level, with the applied base following the line of the floor. In this case, the gap between the top of the base and the wallboard trim will vary as the irregularities of the floor vary. Alternately, the trim can be set at a constant distance from the floor and follow the line of the floor, in which case the edge of the trim may appear out of level. The designer must determine or estimate how much the floor will be out of level and decide which approach to use. If a deeper recess is wanted, a second furred wall can be built out from the primary partition. Standard furring strips can be used or a J-runner can be used with 2-1/2 in. (63.5 mm) metal studs. In this detail or the one shown the designer can determine whatever height of recess is wanted. This detail allows for a thicker base (such as wood or stone), while still retaining a recessed appearance. The disadvantages are the additional cost and construction time. A third way to create a recessed base is by using a proprietary aluminum trim piece. This detail can be used with a single layer of gypsum wallboard because the aluminum closes off the stud space. The trim can be painted or another material adhesive-applied to the trim. However, this detail is limited to the manufacturer's 4-in. (102-mm) height, and because there is no wallboard, a fire rating is not possible and acoustical separation is compromised. -- Recessed base details: (a) double layer wallboard resilient base slight gap as base follows floor line L- or J-trim set level (c) aluminum base trim proprietary base trim 4" (102) (b) furred out wall J-metal runner dimension as required --- Wall-to- floor connections with featured bases: (b) cove (a) emphasized (c) floating floor (d) floating wall Emphasized bases celebrate the transition between the floor plane and the partition plane. They are also appropriate to increase the scale of the base for large rooms or spaces with high ceilings. Cove bases smooth the transition between floor and partition. They are also an excellent way to provide a sanitary base that is easy to clean. In order to be effective the radius of the cove must be large enough to easily perceive and in scale with the room in which it’s used. A floating floor is physically separated from the partition plane at the finish level of the floor. The reveal created may be shallow or deep, depending on the how it’s detailed. A floating floor creates a very distinct separation between the horizontal plane and the vertical plane, although it does create a potential tripping hazard. Like the floating floor, a floating wall physically separates the vertical plane from the horizontal plane with glass filling the gap. If carefully detailed it makes the floor finish appear to continue uninterrupted into the next space and creates a greater sense of space, making the rooms appear larger. To be effective, this detail requires clear floor space, so the glass is not blocked by furniture. -- Featured Bases EMPHASIZED Emphasized bases, are a type of applied base but larger and/or more ornate than standard base treatments. Emphasized bases are usually higher than the standard height of 4 in. (100 mm) of most resilient or wood bases. Emphasized bases are used to complement the scale of larger spaces or when the designer wants to emphasize or strengthen the transition between ground plane and wall plane. Emphasized bases can be formed in a number of ways. The size can simply be increased over standard bases; E.g., by using a 9 in. (229 mm) high wood base instead of a 4-in. (102 mm) high one. The designer can also emphasize the base by building up its complexity as with a multipiece wood base composed of a base, base shoe, and base cap. Other materials can be used in the same way. The base may also be detailed with more than one material to highlight it or add emphasis. COVE Cove bases are those with a noticeable curve as a transition between the vertical plane and the horizontal plane. The curve must be larger than just the small cove built into some resilient base. While the cove base is most commonly used for sanitary reasons, coves may also be used to create a smooth visual transition between the floor and the wall, in some cases making them seem to be one surface. For this type of base to be visually effective, the cove must have a radius of at least 2 in. (50 mm) or more; greater sizes are required if the scale of the room is large. Cove bases are more difficult and expensive to form than other types. One of the most common materials used for cove bases is terrazzo. When used with a terrazzo floor, it provides an easy-to-clean base, suitable for hospitals and other high-maintenance uses. A large cove base can present a safety hazard if people walk close to the wall and step on the curved portion. --- Floating floors (b) moderate reveal railing for safety railing flooring on wood or metal framing gap as wide and deep as designed gap as wide and deep as designed 2" to 3" (50 to 75) 3/4" to 1-1/2" (19 to 38) angle or trim as required hardwood or resilient floor on plywood as designed hardwood or carpet finish (c) deep reveal (a) shallow reveal. FLOATING FLOOR A floating floor has a gap, or reveal, between the edge of the flooring and the wall, making the floor appear to hover within the space. Of all the types of base detailing, the floating floor is the one that is most effective in physically and visually separating the ground plane from the wall plane. This type of floor can be used in retail stores, galleries, restaurants, lobbies, and anyplace where furniture does not need to be placed near the wall. To be most visually effective, this type of base needs to be visible along its entire length. Although it makes a dramatic design statement, the floating floor presents obvious tripping hazards and can be dangerous for visually impaired people. However, if the width of the reveal is minimized, these hazards can be mitigated. A railing attached to the floor or to the wall may also be used to prevent people from walking too close to the gap. The gap may also create cleaning problems if used in an environment where there are large amounts of debris. Some of the methods of detailing this type of floor. In most cases, the depth of the reveal is created by the structure of the finish flooring; both the partition and the flooring rest on the same elevation of sub floor. --- shows a minimal depth of reveal with the finish flooring applied to a thickness of plywood or underlayment. Depending on the type of finish floor, a protective angle may be required to prevent the edge of the flooring from damage. For deeper reveals, the floor can be raised on a platform structure. In all cases, the partition must be constructed and finished before the floor is installed, which may affect the construction schedule. FLOATING WALL A floating wall consists of the solid portion of the partition raised an obvious distance above the ground plane with the space between the ground plane and the bottom of the partition open or filled with glazing. This type of detail has the effect of creating the partition as a screen with the floor continuing uninterrupted below it. It creates a strong visual and actual separation between horizontal and vertical planes. Combined with an opening or glazing along the ceiling line, this design provides an open feeling and allows natural light to penetrate a partition line while maintaining visual privacy. This design is one of the more difficult details to implement, especially if glazing is used to close the opening. One way of detailing this is shown. This detail shows the use of a heavy-gauge metal runner to support the studs. Because most manufacturers supply runners in 10-ft. (3048 mm) lengths this limits the maximum space between supports. For longer spans or heavier walls, a structural steel channel can be used. In either case, a structural engineer should be consulted for recommendations on the exact type, size, and thickness of the member used to support the studs based on the span distance, the height of the wall, and its weight, as well as the type and size of the vertical support member. In addition to structural considerations, electrical and data wiring must be coordinated. Electrical service can be supplied from the ceiling plenum and run horizontally through the studs as with any partition. The steel support member must be punched with holes prior to installation to allow the electrical conduit to pass through them. -- Component wall-to-floor connections: (a) third plane: A third plane transition between the floor and partition emphasizes the line of the base. The plane can be any size or angle and may be finished the same as the floor or partition or may be a different finish. It may incorporate lighting or other features to further emphasize the transition. (c) parallel second plane: A parallel second plane is built out from the primary partition a significant distance. This treatment can both modulate the vertical scale of the space and provide a sense of added depth to an otherwise flat vertical surface. The portion of the plane near the floor can be detailed with a traditional applied base or with other methods. Functionally, this base treatment can conceal services or heating. (b) wainscoting: Wainscoting is the traditional method of finishing the lower portion of a partition. In addition to providing protection from abuse, it can modulate the scale of the room and add visual interest to a space. The portion of the wainscoting near the floor can be detailed with a traditional applied base or with other methods. (d) base as storage: When the base transition is made very large, it can be used for storage. As with a parallel second plane, this detail can modulate the scale of the space as well as provide functional storage space. This detail adds significant depth to the vertical surface. ---- Floating wall: double structural steel studs fastened to runner note: lower portion of wallboard not shown for clarity carpet over bottom leg of angle heavy gauge runner 20 ga., 0.0346 in. (0.88 mm) stud or heavier double aluminum angle fastened to floor 1/4" (25) glass or heavier gap between glass and wallboard sealed with silicone sealant aluminum channel wallboard L-trim ---- Component Bases THIRD PLANE Instead of a standard base, a third plane distinct from the horizontal ground plane and the vertical partition plane can be used to emphasize the transition and create a unique detail. Lighting can be incorporated into this type of detail to give a strong directional sense that may be appropriate in a corridor. The angle can be repeated and the intersection of the wall and the ceiling. Although this detail can be employed for emphasis, this detail can also make the two planes seem to merge, as with a large cove base, if the finish is the same as the partition and ceiling. As with a cove base, a large third plane can create a tripping hazard, so its use is limited to appropriate situations. If the plane is finished with the same material as the partition, there is the issue of durability and maintenance. If the flooring material is carried onto the third plane, it becomes less visible and may be a safety hazard. Both of these potential problems can be mitigated by functionally treating the third plane as a standard base, using a durable, easily maintained material such as plastic laminate or stone. WAINSCOTING Wainscoting is a traditional, practical way to treat the transition between the ground plane and the wall plane, while providing a durable surface as protection from furniture and other activities. From a design standpoint, wainscoting can also be used to change the scale of a room. While traditional wainscoting uses a standard wood base with wood paneling above, material can be selected and detailed so that there is no separate base with the wainscoting being the base. Plastic laminate panels, stone, metal, or wood panels can be used that extend to the floor without a separate base. A trim cap of some type is required at the top of the panel to make the transition between wainscoting and the wall finish above. PARALLEL SECOND PLANE As an extension of the wainscoting concept, a separate plane can be built out from the primary partition, emphasizing not only the height of the transition but also its thickness. This type of detail can be used to modulate the scale of the space, provide a band of durable material, and, if necessary, conceal mechanical or electrical services such as large pipes or heating units. The top of the surface can also be used as a shelf, if necessary. At the floor line, the second plane can be extended to the floor with no separate base or the transition can be treated in any of the other ways discussed in this section. This type of design can be most easily constructed as a furred wall, using a stud depth as required for the functional and aesthetic requirements. If a depth greater than the depth of a stud is required, horizontal and vertical metal framing can be used to build out the third plane to the required dimension. BASE AS STORAGE Finally, the transition between horizontal and vertical planes can be filled with built-in storage. This type of base design is useful where a great deal of storage is required. Because the partition finish above the storage is physically separated from activity within the room, more delicate finish materials may be used on the partition, protected from damage. As with wainscoting and a parallel second plane, this treatment is also useful for modulating the scale of the space. At the floor line, the storage can be extended nearly to the floor with no separate base or the lowest storage shelf can be located a few inches above the floor and the bases at that point treated in any of the other ways discussed in this section. --- Wall-to-ceiling transition concepts: standard ceiling transitions; structural transitions; planar transitions --- Standard wall-to-ceiling connections: (a) none; (c) emphasized trim; (b) minor trim or reveal; (d) reveal A flat wall with an applied base and no trim at the ceiling is the most common type of partition. It’s easy to build, inexpensive, and provides a good base for a wide variety of smooth interior finishes. Most commonly such partitions are gypsum wallboard applied to wood or metal studs. Minor trims or reveals are small in relation to the area of the partition or ceiling. They serve to provide a clear differentiation between the two planes. Reveals create a shadow line and separation between different materials, while small trim can conceal minor irregularities in the joint or at the edges of the ceiling or partition material. Emphasized trim makes a bolder statement than minor trim and celebrates the transition between vertical and horizontal planes. In most cases, the size of the trim should be adjusted to coordinate with the height of the ceiling and the overall scale of the room. Emphasized trim can be built in the traditional way with standard moldings or be built up of more contemporary square-edged elements. A reveal transition provides a major separation between the ceiling plane and the partition. It’s larger than a minor reveal and makes a bold, contemporary statement. The reveal may be finished the same as the partition or it may be a contrasting color or finish. -- WALL TO CEILING The connection of the wall plane to the ceiling plane is one of the most important in interior design because it joins two of the most prominent architectural features and because it’s always within view of a room's occupants. In contemporary construction, it’s also one of the least considered, which is unfortunate because the way the vertical and horizontal ceiling planes are connected can affect the scale and feeling of a space as well as solving many functional problems such as material transition, support, and lighting. Some of the general types of wall-to-ceiling connection are shown. Which detailing approach is used depends on whether the designer wants to give equal weight to both the ceiling and partition or whether the goal is to visually separate the two planes. Each of these is discussed in more detail in the following sections. As with the wall-to- floor transition, each detailing approach produces a unique design effect useful for different design goals. E.g., continuing the ceiling material partially can also minimize the visual importance of the connection, giving equal visual weight to both planes. It also is generally viewed as contemporary in style and imparts a feeling of simplicity. In residential construction and commercial construction where the partition and ceiling are both finished with gypsum wallboard, the joint is simply a continuation of the wallboard. Only the final finish of paint or wallcovering may differentiate the two planes. In commercial construction when the ceiling is a suspended acoustical ceiling, the transition may simply be a standard ceiling angle if the partition continues through the ceiling or there may be no trim at all if the ceiling continues over the top of the partition. --- Vertical ceiling reveals: (a) F reveal molding (c) ceiling trim (b) F reveal varies: 1/8" to 3" (3 to 76) varies: 3/4" to 3" (19 to 76) 1/2" or 5/8" (13 or 16) acoustical ceiling acoustical ceiling gypsum wallboard. -- MINOR TRIM OR REVEAL Small trim is sometimes used to conceal the joint between the partition and ceiling or to provide a minor shadow line for visual interest. A reveal may also be used to differentiate down the wall increases the apparent area of the ceiling and lowers the apparent height of the wall. The types of transitions can be grouped into three general categories: standard ceiling transitions, structural transitions, and planar transitions. Standard Ceiling Transitions Standard ceiling transitions are those that are commonly used and are the traditional methods of treating the junction of the wall and ceiling plane. They are generally small in scale, simple to construct, and resolve the typical functional problems of ceiling construction. NO TRANSITION No detailing connection is, of course, the simplest and least expensive to construct, which is why it’s used so often. However, a simple 90-degree joint between the two planes or for strictly functional reasons, such as to make painting or finishing easier, to accommodate irregular surfaces, or to eliminate the need for a standard ceiling angel for acoustical ceilings. A reveal can be created by using standard gypsum wallboard trim and a standard ceiling angle, but there are proprietary aluminum trim pieces that can accommodate different conditions and ceiling materials. Refer to Table 3 for a list of trim manufacturers. However, if a fire-rated or acoustical partition is required, a second layer of wallboard is necessary. EMPHASIZED TRIM Emphasized trim is molding or other material used to highlight the intersection of the wall and ceiling planes. Traditionally, this has been accomplished with crown molding or wood molding built up of individual pieces. The appearance of wood can also be created with traditional plaster molding, medium-density fiberboard, or high-density polyurethane molding with the same pro files as traditional wood molding. Emphasized trims such as cornice molding reflect a more traditional approach to this transition of surfaces without giving more weight to either plane. For contemporary designs, a pro file other than one of the traditional shapes can be used to accomplish the same design goals. REVEAL As with floor-to-wall connections, using reveals, or physically separating the two planes tend to emphasize the ceiling plane, depending on what materials, finishes, and colors are used. Like recessed bases, this type of detail generally requires a double layer application of wallboard or the second layer of framing and wallboard. If a ceiling reveal is used with a matching recessed base (and possible reveals at the wall-to-wall intersection), the partition takes on the appearance of a separate vertical plane floating away from another surface. Structural Transitions Structural transitions between the partition and the ceiling have a distinct and signi ficant piece of construction at the intersection of vertical and horizontal planes. In most cases, these types of transitions are made for practical reasons as well as to modify the scale or appearance of the space. E.g., coves provide a way to provide indirect, ambient lighting in a room. SOFFIT A soffit is an area built down from the ceiling and away from the wall. In most cases, a soffit is constructed with wood or metal framing and covered with gypsum wallboard. One of the common uses of a soffit is to fill the space above wall cabinets that don’t extend to the ceiling. However, soffits can also be used to conceal structural elements or mechanical services, contain lighting, emphasize a wall area, or modulate the scale of a space. --- Structural wall-to-ceiling connections (b) ceiling plane continuity (d) cove (c) floating ceiling (a) soffit Soffits are small areas of the total ceiling area built down from the elevation of the main ceiling plane. Soffits can be used to emphasize high areas of a ceiling, to conceal mechanical services, or to fill an area above cabinets. The intersection between the ceiling plane and the partition plane can be virtually eliminated by continuing the ceiling across a partition and filling the gap with glazing or by leaving it open. In most cases, the gap is filled with glazing that provides acoustical separation, while allowing light to flow from one space to another. Floating ceilings create a definite separation between the partition plane and the overhead plane. If the ceiling is carried close to the partitions, it seems that the partition disappears behind the ceiling. If the floating ceiling is composed of separate "clouds" of overhead elements the ceiling has additional depth with the space above flowing between several heights. Coves are often used to conceal indirect lighting, but they can also be used to modulate the scale of a room and conceal air supply and return grilles. Coves can be constructed with simple, rectangular shapes or be finished in more traditional molding profiles. --- Ceiling continuity over glazing: 3/4" x 3/4" (19 x 19) channel wallboard L-trim ceiling angle edge of wall beyond metal or wood support-brace to structure above as required aluminum channel glazing CEILING PLANE CONTINUITY Ceiling plane continuity refers to the use of glazing at the top of the partition so that the ceiling appears to continue from one space to another. This detail is an excellent way to make spaces appear larger and to allow daylight to penetrate into interior spaces while maintaining visual privacy. If the intent is to allow daylight penetration, any type of framing can be used, from standard wood or metal frames to frameless glazing. However, if the design intent is also to minimize framing and make it appear that the ceiling continues uninterrupted, a detail like that can be used. With this type of frameless glazing, the vertical joints between glazing can be sealed with silicone sealant if acoustical control is required or left open. If the partition must be fire rated, fire-resistance-rated glazing and framing can be used, but the size of the framing can be significant. --- Horizontal ceiling reveals (a) W-molding (b) T-molding 3/4" (19) 1/2" to 1-1/8" (13 to 29) acoustical ceiling gypsum wallboard available from 2" to 12" (50 to 300) acoustical or wallboard ceiling (c) aluminum perimeter trim clipped to ceiling grid FLOATING CEILING Floating ceilings physically and visually separate the ceiling plane from the partition. The effect can be used with a continuous, planar ceiling, as discussed or with semi-closed or floating planar ceilings illustrated. This type of transition emphasizes the overhead plane by separating it from the partitions and treating it as a unique construction element. Three ways to detail this are shown. To create indirect lighting washing down the wall, fluorescent lamps or other types of luminaires can be placed at the edge of the ceiling. Not only is this an interesting indirect lighting method but it also further emphasizes the separation of the horizontal and vertical planes. Floating ceilings can be created in a number of ways. Some of these are shown. Standard gypsum wallboard ceilings can be used with metal framing to trim the edges or a prefabricated edge treatment can be used. Refer to manufacturers that supply edge trim as well as complete floating ceiling assemblies. COVE A cove is a separate molding or construction assembly running horizontally near the ceiling line. In addition to its decorative uses and as a way to modulate the scale of the room, coves can be used to provide indirect lighting onto the ceiling. Coves can be as small as standard cornice molding installed away from the ceiling plane or as large as required for the visual effect and lighting needed by the designer. In addition to making the transition between wall and ceiling planes less abrupt, coves can solve practical problems such as providing lighting or concealing air supply registers and exhausts. Coves that are constructed of wood or metal framing or prefabricated aluminum sections can be used to support luminaires. The aluminum cove sections are available in a variety of pro files and are screwed to the studs with flanges on a support bracket. The finish pro file is then secured to the bracket. Wallboard flanges provide for taping and finishing, making a smooth transition between the trim and the gypsum wallboard. Planar Transitions Planar transitions are those that provide a change of plane from the ceiling to the partition with a single surface. There are four general types of such transitions. -- Lighting coves (a) metal framing cove (b) prefabricated cove (c) cove at ceiling height change --Planar wall-to-ceiling connections (c) parallel second plane (d) band (b) third plane (a) continuity of material Making a smooth transition between the vertical plane and the horizontal plane deemphasizes the joint between them. Most often created with a circular curve, a ceiling transition lowers the apparent height of the ceiling. A third plane transition between the partition and the ceiling tends to emphasize the intersection and creates an additional plane of interest. The plane can be finished the same way as the ceiling, in which case, it will also tend to lower the apparent height of the room, as with a cove, or it can be finished the same way as the partition. For added emphasis, the third plane can be finished with a different color or texture than the other two planes. A second plane, parallel to the partition, modulates the height of the room and adds a third dimension to an otherwise flat wall surface. The plane can be finished the same way as the wall, but it also provides an opportunity to add a separate band of color or texture to the vertical surface. A ceiling band is a small, but noticeable, thickness built out from the wall. It’s similar to a wainscot but in reverse. Bands are useful for modulating the scale of a room, much like a parallel second plane, and provide a surface for decoration, signage, or other features. -- CONTINUITY OF MATERIAL With continuity of material, the finish of either the ceiling or the partition is continued onto the other plane with a smooth, uninterrupted surface. This is most often done with a curve as shown. This design detail blends the two surfaces and deemphasizes the corner and the junction of the two planes. When the ceiling material is continued partially down the wall, this also tends to lower the partition's apparent height. However, for this design to work the curve must be sufficiently large to create the desired effect. Small coves can be created with wood molding or plaster, but a more efficient method is to use aluminum trim, which is available in a variety of radii, from 3/4 in. (19 mm) to 6 in. (152 mm). This trim is attached to the framing and provides flanges for using wallboard joint compound to smooth the curve into the gypsum wallboard. Larger radii can be created with curved wallboard, plaster, or gypsum-reinforced fiberglass. THIRD PLANE As with a floor-to-partition transition, a third plane tends to emphasize the transition between the ceiling plane and the partition plane, especially if it’s finished differently than either the partition or the ceiling. When it’s finished the same as either the partition or the ceiling, it may make the two planes appear to merge, but if this is the intent a cove transition works better. Depending on the size needed for the third plane, it can be constructed with molding, veneer panels, or wallboard framed with wood or metal studs. PARALLEL SECOND PLANE A parallel second plane, show, creates a built-out wall section parallel to the partition with a noticeable height and thickness. As with a flooring transition, this detail can be used to modulate the scale of the space and create a three dimensional interest. However, unlike a second plane at the floor level, this detail does not reduce the usable area at the floor. Because of the thickness, additional trim can be installed between the partition and the built-out section using other techniques described in this section. The parallel second plane can be constructed using one of the methods of creating raised faces. BAND A ceiling band, similar to wainscoting, is a separate, distinct edging built out slightly from the partition. This detail can be used to modulate the scale of a room and to emphasize the difference between the vertical and horizontal planes. It’s less costly to construct than a parallel second plane but often creates the same type of effect. A ceiling band can be created by using an additional layer of gypsum wallboard with edge trim, with veneer paneling, thin stone, or other material, as appropriate. It can also be combined with other transition details as described in this section. Previous: |