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CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 13/301,428, which claims priority on U.S. Provisional Application Ser. No. 61/458,304 filed on Nov. 19, 2010, the disclosures of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to a series of removable bulkheads which surround and protect immovable building fixtures such as sprinkler and plumbing lines, heating and ventilation ducts, and electrical and telecommunications wiring. 
         [0003]    Building managers which administer residential and commercial leases often have to renovate rental properties to meet the needs of a tenant or renovate because of changes to municipal building codes. Rental properties can have a variety of utilities, such as piping, fire protection, electrical wiring, heating and ventilation ducts, and telecommunications wiring. Since in most properties, large portions of utilities like ventilation ducts, water piping, sprinklers, and electrical wiring are hidden behind finished ceilings and walls due to aesthetic concerns, building mangers need to hire carpenters to open up these ceilings and walls in order to access these utilities to perform renovations. Once a renovation is complete, a carpenter needs to be retained again to refinish these exposed ceilings and walls. In order to refinish the ceiling or wall, a carpenter will have to close the hole in the exposed ceiling or wall. A common technique used to refinished exposed ceilings and walls is drywalling. 
         [0004]    Drywalling is a construction technique which involves the installation of gypsum plaster panels pressed between two thick sheets of paper or fiberglass, which are commonly known as drywall. Drywall is installed by first being cut to size by a carpenter to cover the exposed area, then attached to wall studs or ceiling joists using nails, glue, or screws. After the panels are secured to the studs or ceiling joists, the space between the panels of drywall and the existing wall must be covered with joint tape. Next, several layers of a mud like paste known as joint compound is then applied to the exposed surfaces of the panels. Finally, the exposed surface is sanded and then painted. 
         [0005]    The drywalling technique has several inherent problems. First, drywall is very heavy making it difficult to handle and install. Drywall is also very brittle and prone to cracking and flaking when handled improperly. Application of joint compound to the exposed surface of the panels is a very messy process and compound will invariably get into unintended areas. For example, when drywall is installed near a sprinkler line, joint compound can infiltrate the sprinkler line and create clogs. New clogs in the sprinkler line require the retention of a sprinkler contractor for a second time, and a carpenter to open and reclose the ceiling. 
         [0006]    The added expense of retaining two contractors to repeat the same work can significantly add to rental property&#39;s operating costs. The added time necessary for contractors to open a ceiling, re-fix a utility, and reclose a ceiling can add weeks, months, and sometimes years to the time it takes for a tenant to move into a rental property. This additional time can cause a significant loss of rental income for landlords. Commercial tenants would also lose income from their inability to utilize their rental space to carry on their business. Residential tenants would be forced to bear the additional cost of finding temporary housing. 
         [0007]    Another problem associated with using drywall is that it generates a large amount of waste. Drywall is only sold in large sheets and in order to refinish a ceiling or patch a wall a carpenter will invariably need to cut much smaller pieces from the larger pieces. Once the smaller pieces are cut, the larger sheets almost always become useless because their shape has now become irregular, and are discarded as waste. 
         [0008]    Another problem associated with using the dry wall technique is the time it takes to complete. The drywall needs to be cut, attached, taped, covered with joint compound, sanded, then painted. Each step relies on a different skill set to complete and is an opportunity to damage a nearby utility. Putting drywall to refinish the ceiling of an average sized room could take anywhere between 4 to 7 days. 
         [0009]    Thus, the problem of a quick and cost effective method for carpenters to refinish the ceilings and walls that house the utilities of a property remains. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention is directed towards a series of removable bulkheads which surround and protect immovable building fixtures such as sprinkler and plumbing lines, heating and ventilation ducts, electrical and telecommunications wiring. A single bulkhead is generally comprised of a vertical panel attached to a horizontal panel. The bulkheads attach to preexisting ceilings and walls and provide a quick and cost effective method of concealing fixtures and allows easy access to renovate or repair the fixtures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of a first embodiment of the bulkhead of the present invention, prior to bending. 
           [0012]      FIG. 1A  is a cross-sectional view through the recess of the bulkhead of  FIG. 1 . 
           [0013]      FIG. 1B  is a perspective view of the bulkhead of  FIG. 1 , after bending. 
           [0014]      FIG. 2  is a cross-sectional view of the bulkhead of  FIG. 1B  installed using a first method of installing the bulkhead. 
           [0015]      FIG. 2A  is a cross-sectional view of the bulkhead of  FIG. 1B  as it is being advanced toward the nailing strips in the first method of installing the bulkhead. 
           [0016]      FIG. 2B  is a cross-sectional view of the bulkhead of  FIG. 2A , as it is being advanced first toward the wall and then toward the ceiling, in the second method of installing the bulkhead, with a first nailing strip attached to the vertical portion of the bulkhead using quick release fasteners. 
           [0017]      FIG. 2C  is the cross-sectional view of  FIG. 2B , with the nail of the nailing strip attached to the vertical portion of the bulkhead being depressed into the ceiling to form pilot holes therein. 
           [0018]      FIG. 2D  is a cross-sectional view of the bulkhead of  FIG. 2C , as it is being advanced first toward the ceiling and then toward the wall, in the second method of installing the bulkhead, with the first nailing strip having been secured to the ceiling using nails, and with a second nailing strip attached to the horizontal portion of the bulkhead using quick release fasteners. 
           [0019]      FIG. 2E  is the cross-sectional view of  FIG. 2D , with the nail of the second nailing strip attached to the horizontal portion of the bulkhead being depressed into the wall to form pilot holes therein. 
           [0020]      FIG. 3  is a perspective view of two bulkheads as embodied in  FIG. 1  just prior to installation using nailing strips of the present invention that are secured to a wall and ceiling. 
           [0021]      FIG. 4  is a perspective view of two bulkheads of a second embodiment, with a joining block inserted at one end. 
           [0022]      FIG. 4A  is a perspective view of the two bulkheads of  FIG. 4 , but with the joining block inserted at the opposite end. 
           [0023]      FIG. 5  is a perspective view of two bulkheads of  FIG. 4  having been joined together, and with nailing strips of the present invention secured to the wall and ceiling. 
           [0024]      FIG. 6  is another perspective view of a bulkhead of the present invention with the rear end having a mortise and the front end having a tenon. 
           [0025]      FIG. 7  is a perspective view of a bulkhead of the present invention with double mortise opening at each end, and with a “u” shaped joining member shown prior to insertion into one pair of the mortises. 
           [0026]      FIG. 8  is a perspective view of two joined bulkheads, with first and second end cap panels displaced therefrom, and being shown just prior to installation into the ends of the bulkhead. 
           [0027]      FIG. 9  is a perspective view of a second embodiment of the bulkhead of the present invention. 
           [0028]      FIG. 9A  is a cross-sectional view through the recess of the bulkhead of  FIG. 9 . 
           [0029]      FIG. 9B  is a perspective view of the bulkhead of  FIG. 9 , after bending. 
           [0030]      FIG. 9C  is a cross-sectional view through a third embodiment of the bulkhead of the present invention, which may comprise two rigid outer layers that may transition therebetween, using a flexible material. 
           [0031]      FIG. 10  is a vertical cross-sectional view of the vertical and horizontal panels of the present invention meeting to form a butt joint. 
           [0032]      FIG. 11  is a vertical cross-sectional view of the vertical and horizontal panels of the present invention meeting to form an end lap joint. 
           [0033]      FIG. 12  is a vertical cross-sectional view of the vertical and horizontal panels of the present invention meeting to form a mortise joint. 
           [0034]      FIG. 13  is a cross-sectional view of the bulkheads of the present invention, where the bulkhead is secured with tenons on the bulkhead being received in mortises in the nailing strips. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0035]    The present invention is directed towards a series of removable bulkheads which surround and protect immovable building fixtures such as sprinkler and plumbing lines, heating and ventilation ducts, electrical and telecommunications wiring. A bulkhead could just be an upright partition creating a compartment, according to the traditional definition. However, as utilized herein, the removable bulkhead may comprise a specially constructed panel and associated installation procedure, in which only a portion may be in the upright position. Each of the sections of the bulkhead may be formed of generally flat surfaces as shown in  FIG. 1 , or they may have curved portions or may be completely curved to accommodate any aesthetic or functional design requirement. Also, the bulkhead may be comprised of any rigid board material that can be painted, such as fiberglass, plywood, masonite, plastic, etc. 
         [0036]    Two different approaches for manufacturing of the bulkhead may be taken. In a first embodiment, illustrated initially in  FIGS. 1 ,  1 A, and  1 B, the finished bulkhead  50  may be manufactured using hardboard. Hardboard is a type of fiberboard, which comes in three different varieties. Listed in order of increasing density, those fiberboard varieties are particle board, medium-density fiberboard, which is utilized heavily in the furniture industry along with wood veneers, and hardboard. Hardboard is made from exploded wood fibers that have been highly compressed. In this first embodiment, a bulkhead may be formed from a length of a three-layered piece of hardboard. The length and width of the piece  50 P of hardboard may be selected to produce a standard sized bulkhead panel  50 , as discussed hereinafter. 
         [0037]    The piece of hardboard  50 P may be cut to be generally rectangular, having a top surface  50 P i  and a bottom surface  50 P ii  being generally parallel to each other; a first end surface  50 P iii  and a second end surface  50 P iv  being generally parallel to each other, and being generally orthogonal to the generally parallel top and bottom surfaces  50 P i  and  50 P ii ; and a first side surface  50 P v  and a second side surface  50 P vi , with the first side surface  50 P v  being generally orthogonal to the generally parallel top and bottom surfaces  50 P i  and  50 P ii , and also being generally orthogonal to the generally parallel first and second end surfaces  50 P iii  and  50 P iv . 
         [0038]    As seen in  FIGS. 1 and 1A , the piece of hardboard  50 P may have a machined recess  50 PR that may be formed using a CNC machine. The recess  50 PR may run the entire length L of hardboard  50 P, running along the top surface  50 P i  and penetrating down and possibly even into to the third layer  53 . The recess  50 PR may generally form a V-shaped notch having a first side surface  50 PR i  and second side surface  50 PR ii , each of which may be at a 45 degree angle to the generally flat top surface  50 P i . Therefore, the first side surface  50 PR i  and second side surface  50 PR ii  may be orthogonal to each other. At the base of the recess (near second side  50 PR ii ) may be a relief groove that may be radiused. 
         [0039]    To convert the machined hardboard panel  50 P of  FIG. 1  into the L-shaped bulkhead panel  50  of  FIG. 1B , the portion H must be bent approximately 90 degrees about the recess, as shown by the curved arrow in  FIG. 1 , so that the portion H is then horizontal. To better accommodate bending of the hardboard panel  50 P and inhibit tearing or splintering at the recess  50 PR, a piece of tape  55  may be attached to bottom surface  50 P ii , so as to run down the length L of the surface between first end surface  50 P iii  and second end surface  50 P iv . In addition, to help in securing the folded hardboard panel and prevent any spring-back after the folding process is completed, a piece of double-sided tape  56  may be secured to either first side surface  50 PR i , or to second side surface  50 PR ii  of recess  50 PR, so as to run down the length L of the surface between first end surface  50 P iii  and second end surface  50 P iv . The tap may be an acrylic tape. After performing the bending operation, which may also utilize an application of water or other softening agent to make the hardboard temporarily more pliable, and with the tape securing the vertical and horizontal bulkhead portions together, whereby first side surface  50 PR i  of recess  50 PR is now generally parallel and proximate to second side surface  50 PR ii , mechanical fasteners such as screws, may, but need not necessarily be, driven into the bend of the joint to more positively secure the joint. (Note—this approach to manufacturing the L-shaped bulkhead  50  may also be used to construct a U-shaped bulkhead that would begin with a hardboard panel having two recesses, and which may be secured to the ceiling). 
         [0040]    The bulkhead  50  can be secured to an existing wall and ceiling, along which may run utility or other fixtures  18 , such as: water piping, electrical wiring, heating or ventilation ducts, and telecom wiring runs along. A first installation method of the bulkhead panel  50  may be seen in  FIG. 2 . In the first installation method, two nailing strips  24  may be installed upon a building wall  16  and two nailing strips  24  may be installed upon a ceiling  17 , with the strips being parallel to each other, and being separated according to the final dimensions of the bulkhead  50 . The nailing strips  24  may be rectangular and be comprised of any material that is capable of receiving mechanical fasteners like nails or screws, and which is also capable of supporting the weight of the bulkhead. The nailing strips  24  can be secured to the wall and ceiling using any suitable mechanical fastening arrangement. The strip  24  may simply be nailed in place using, for example, fifteen gauge headless nails  25 , or strip  24  may be secured using wood screws, or screws with plastic anchors, or molly bolts, etc, depending upon the make-up of the wall/ceiling structure. The nailing strips  24  can be manufactured with predrilled pilot holes for receiving the fasteners used in securing of the strips to the wall and ceiling, to permit a faster and or easier installation. In a preferred embodiment, two pairs of strips  24  are used for every 8 feet of length of the bulkhead  50 . 
         [0041]    In certain states, an asbestos abatement issue may arise as a result of penetrating into or otherwise disturbing a ceiling or wall of an older structure that contains asbestos in amounts that exceed so-called “trigger levels.” Where these levels are found, a certified removal contractor (General Abatement Contractor) must remove asbestos-containing materials prior to the renovation. (see e.g., http://www.cdphe.state.co.us/ap/asbestos/renodemo.pdf). Therefore, the nailing strips  24  may also be installed upon the wall and ceiling through the use of adhesives, to avoid the need for triggering additional work. The use of adhesive may also be desirable for the nailing strip installation upon “popcorn” style acoustic ceilings, which also routinely contained asbestos in the past. 
         [0042]    Following installation of the nailing strips  24 , as seen in  FIG. 2A , the bulkhead  50  may be advanced toward the nailing strips so that the vertical portion of inner surface  50 P i  of the bulkhead  50  is aligned with the nailing strip  24  vertical outer contact surface  24 Vo of the strip secured to the ceiling  17 , and with the horizontal portion of inner surface  50 P i  of the bulkhead  50  being aligned with the nailing strip  24  horizontal outer contact surface  24 Ho of the strip secured to the wall  16  ( FIG. 2 ) Next, nails or screws  25  may be driven into the vertical and horizontal portions of outer surface  50 Pii of the bulkhead to secure the bulkhead to the nailing strips  24 . Rather than securing the bulkhead  50  to nailing strips  24  using mechanical fasteners, adhesive may instead be used. After securing the bulkhead  50  to the nailing strips  24 , any gaps at the interface between the bulkhead  50  and ceiling  17 , as well as between the bulkhead  50  and wall  16  may be taped and/or caulked to conceal the appearance of the seams. 
         [0043]    When access to the utilities or fixtures  18  is necessary, all that is required is the removal of the nails or screws  25  that were used to secure the bulkheads to the nailing strips  24 . Once the nails or screws  25  are removed, the utilities or fixtures  18  will be freely accessible for renovations. Once renovations are complete, the bulkheads can be reattached to the existing walls  16  and/or ceilings  17  using the nailing strips. 
         [0044]    The length L of the bulkhead  50  may be constructed in 8 foot increments, or other incremental lengths to meet various design and aesthetic construction requirements. In a preferred embodiment, the length of the bulkhead is 8 feet. The lengths of the vertical and horizontal portions or legs of the L-shaped bulkhead  50  can also be varied to meet various design and aesthetic requirements, and may be manufactured in several standard sizes, such as: 6″ by 6″, 8″ by 8″, 8″ by 10″, 12″ by 12″, and 18″ by 18″, etc. The thickness of the hardboard panel used to create the bulkhead may also be varied accordingly for the size of the leg, and particular strength requirements or other considerations. 
         [0045]    The legs (vertical and horizontal portions) of the standard bulkhead  50  may also have cutouts therein so as to be contoured about any geometric irregularities in the walls and/or ceiling in the region in which the bulkhead is to be installed. Also, the vertical and horizontal portions of the bulkhead may be manufactured with any number of orifices to accommodate transverse passage of any object, such as wiring, etc. Moreover, in an alternate embodiment, the ends of the horizontal and/or vertical portions of the bulkhead  50  may be grooved, which may serve two functions. 
         [0046]    First, such a groove may be utilized so that two or more bulkheads  10  can be joined to each another. In one embodiment, as seen for the first end  51  of the bulkhead shown in  FIG. 4A , a groove  53  is cut in either of, or both of, the first and second ends,  51  and  52 , of the bulkhead  50 . The groove  53  allows for the insertion of a joining wood block  30 , which is also shown therein, being displaced from the bulkhead. The size and shape of joining wood block  30 , must correspond to the size and shape of the groove  53  in the bulkhead  10 , and may preferably be engaged therein in a slight clearance fit or a slight interference fit, depending upon how it is ultimately secured within the groove  53 . The joining wood block  30  may be secured inside the groove  53  by any conventional means, such as adhesive, nails, screws, staples, etc. Where adhesive is used, a slight clearance fit may preferably be used in order to account for the thickness of a layer of the adhesive. Once a first end  31  of the joining wood block  30  is secured within a groove  53  of a first end  51  of bulkhead  50 , the second end  32  of joining wood block  30  may next be secured to another groove  53 A of a second end  52  of another bulkhead  50 A, as shown in  FIG. 4 , to create the joined bulkheads seen in  FIG. 5 . A series of bulkheads  50 ,  50 A,  50 B, etc., may be assembled together in this manner to accommodate any length of room and fixtures. 
         [0047]    A different means of joining the bulkheads is shown by the alternative bulkhead embodiment of  FIG. 6 , where the second end  52  of each bulkhead  50  may have at least one mortise  35 , and the first end  51  may have a tenon  37  of corresponding shape and size. In this embodiment, in order to attach one bulkhead  10  to another, the mortise  35  on the second end  52  of one bulkhead receives the tenon  37  on the first end  51  of another by bulkhead. The resulting mortise and tenon joint can be reinforced by using glue or caulk. 
         [0048]    In another embodiment, shown in  FIG. 7 , the second end  52  and first end  51  of each bulkhead  50 F may have at least two mortises  38  and a groove  38 G with a size and shape capable of receiving one-half of the “H” shaped joining member  39 . One-half of the “H” shaped member  39  may be received in and secured to the mortises  38  and groove  38 G of one end of the bulkhead  50 F, while the other one-half of the “H” shaped member  39  may be received in and secured to the mortises and groove of another bulkhead. The one-half portion of the “H” shaped joining member  39  may be secured inside each of the two mortises  38  and groove  38 G of each bulkhead  50 F by any conventional means, such as: adhesive, nails, staples, etc. 
         [0049]    Another use of the aforementioned groove at the ends of the bulkhead  50  may comprise utilized after the installation of the finished bulkhead  50  against the buildings wall and ceiling, where it does not span between two walls (or utilization even prior to its installation—see  FIG. 8 ), such that an end cap panel  70  is secured in a groove  54  at opposite ends of a bulkhead or a series of bulkheads, so as to be able to completely enclose fixtures therein. The end cap panel  70  may be a single panel constructed of the same material used to form the bulkhead. The dimensions of the end cap panel  70  will generally correspond to the cross section of the bulkhead  50 C/ 50 D at the grooved ends, such that once the front and rear caps are installed, the interior of the bulkhead may be completely obscured. The end cap panel  70  can be secured within the groove  54  of the respective ends of the bulkheads  50 C and  50 D by any conventional means, such as: nails, screws, adhesive, staples, etc. 
         [0050]    To accommodate easier initial installation, and subsequent removal and re-installation of the bulkhead, a single longer nailing strip  24 A may be used, as shown in  FIG. 3 . In addition, rather than using nails or screws for securing the bulkhead thereto, quick release fasteners  26  may be used, such as a variety of the Camloc available from Alcoa Fastening Systems, which is located at 8001 Imperial Drive, Waco, Tex. (see www.afscamloc.net/prod1.php?lang=en&amp;ID=6 and http://pdf.directindustry.com/pdf/camloc/camlock-quick-release-fasteners/56993-66819.html with the disclosures of each being incorporated herein by reference). As seen in  FIG. 3 , three quick release fasteners  26  may be pre-installed in the bulkhead on the vertical portion and three may also be installed in the horizontal portion, where those fasteners may be received through pre-drilled holes and pre-installed corresponding receptacles within the longer nailing strip  24 A. The quick-release Camloc may only require one-quarter of a turn to thereby be engaged with, or disengaged from, the corresponding receptacle within the nailing strip. This arrangement leads to a vastly simplified method of initially installing the nailing strips and bulkhead without measurements, which is seen within  FIGS. 2B-2E . 
         [0051]    As seen in  FIG. 2A , the bulkhead  50  may have a first nailing strip  24 A attached to the vertical portion of the bulkhead using quick release fasteners, and with the nailing strip having a nail  25  having been pre-hammered therein so as to only protrude a small amount from the nailing strip. The bulkhead is then advanced first toward the wall  16  so that surface  50 P vi  contacts the wall, and the bulkhead is then advanced toward the ceiling, so that the first nailing strip  24 A contacts the ceiling  17 , causing the protruding nails to create small pilot holes therein ( FIG. 2C ). To make the pilot holes more immediately visible in the ceiling, a small amount of paint may be blotted onto the tip of the nail  15  prior to advancing the bulkhead as just described. Next, as seen in  FIG. 2D , the bulkhead is then backed away from the ceiling and wall, the first nailing strip  24 A is detached from the bulkhead using the one-quarter-turn quick release fasteners, and is nailed in place on the ceiling  17  using the pilot holes therein. A second nailing strip  24 A is also then attached to the horizontal portion of the bulkhead. Next, as seen in  FIG. 2C , the bulkhead is now first being advanced toward the ceiling until the surface  50 Pv (see  FIG. 2D ) contacts the ceiling  17 , and is then advanced toward the wall  16 , so that the nails of the second nailing strip attached to the horizontal portion of the bulkhead are depressed into the wall to form pilot holes therein. The bulkhead  50  can once again be backed away, the second nailing strip  24 A may be removed detached from the bulkhead using the one-quarter-turn quick release fasteners, and is nailed in place on the wall  16  using the pilot holes just formed therein. The bulkhead can now being removably secured to the nailing strips using the quarter-turn quick release fasteners, with the nailing strips being ideally positioned on the ceiling and wall to support the bulkhead. 
         [0052]    In an alternative embodiment for the manufacturing of the bulkhead, a single removable bulkhead  10  ( FIGS. 9 ,  9 A, and  9 B) may comprise a panel having an inner layer  20  and outer layer  22 , and a core  21 . The inner layer  20  and outer layer  22  of the bulkhead  10  may be comprised of a rigid board material that can be painted, such as fiberglass, plywood, masonite, plastic, and particle board. The outer layer  22 , as seen in  FIG. 9A , may be machined to have the V-shaped recess therein to complete the recess  10 PR of the panel. The machined process in outer layer  22  may result in a remaining local thickness of the layer at the V-shaped recess being as small as 0.001 inches. A machining process that actually pierces the layer  22  to form two separate parts is not detrimental, and comprises an alternative method of assembling the bulkhead. However, retaining the small thickness (0.001 or slightly greater) at the V-shaped recess to have a single hardboard part forming layer  22  may be advantageous to simplify the bulkhead assembly process (taping and bending). 
         [0053]    The core  21 , which may be a honeycomb type of core, may generally be comprised of polystyrene with an ASTM E84 Flame Spread rating of 5-10 and 60-200 smoke development, which is 35% less than conventional dry wall. In a preferred embodiment, the thickness of each of the vertical and horizontal portions of bulkhead  10  may be ¾ of an inch, which may preferably be formed using an inner layer  20  and outer layer  22  of hardboard being 0.08 inches in thickness, and a core being 0.59 inches thick. However, the panel thickness may be constructed to have a finished thickness of 3 inches, or even greater. The three layers may be bonded together like a “glulam” (glued laminated timber product). In a preferred embodiment, an 8 foot length of bulkhead  10  with a 6″ by 6″ cross section will weigh less than 10 pounds. In another embodiment, a sheet of Formica may be applied to the outer surface of the bulkhead  10  using adhesive, or any other conventional method. 
         [0054]    Where the outer layer is a hardboard type of material, the bulkhead may be formed as previously described, i.e., bending to obtain the L-shape. However, in an alternative arrangement, the bulkhead may be manufactured to be a composite honeycomb core sandwich panel. The bulkhead  11  shown in  FIG. 9C  may comprise at least two rigid outer layers sections that may transition therebetween, in the region near the bottom valley  10 PRv of the V-shaped recess  10 PR, using a flexible material, such as by integrating into the third layer, one or more layers of a rubber-like material, which obviates the need for the tape and the bending procedure. The L-shaped bulkhead  11  may then be formed, when desired, by simply folding the two panel sections. To accommodate and simplify the panel&#39;s installation, the L-shape of the panel may be maintained by securing eyelet screws  27  to each of the two panels, as seen in  FIG. 9B , and then by limiting the movements of the two panels by connecting a member, such as a wire or bungee cord, between the two eyelets. This arrangement may also undergo the installation procedures of  FIGS. 2B-2E . Moreover, where a quickly removable bungee cord with hooked ends is used to limit travel of the panels sections and where the eyelet screws are positioned near one of the ends of the panel, instead of the center, removal of the bulkhead after locating the nailing strip  24  in  FIG. 2E  is obviated. Instead, the vertical portion may be secured to the nailing strip previously installed on the ceiling using the Camlocs, and the bungee temporarily unhooked to permit rotation of the horizontal panel portion and removal of the nailing strips therefrom, so that they may be secured to the wall  16  using the newly formed, paint-marked, pilot holes. The horizontal panel portion may then be re-attached to the nailing strip  24  now installed on wall  16 , using the Camlocs. In addition, future access to the to the fixtures would not even require complete removal of the bulkhead, and instead, only the horizontal panel portion secured to the nailing strips  24  on the wall  16  need be disconnected. 
         [0055]    In another alternative embodiment for manufacturing the bulkhead, as shown in  FIG. 10 , a separated vertical panel portion can attach to a separate horizontal panel portion to form a butt joint  32 . This butt joint may be reinforced by drilling at least one hole through a bottom surface  33  of the horizontal panel  3 , and into the vertical panel, and inserting a screw  25 , nail, dowel, or cylindrical disk. In another embodiment, the vertical panel portion can attach to the horizontal panel portion to form an end lap joint  34 , as shown in  FIG. 11 . In another embodiment, the vertical panel portion can attach to the horizontal panel portion to form mortise joint  35 , as shown in  FIG. 12 . The vertical panel can be secured to the horizontal panel, regardless of the joint used, by any number of conventional methods, such as: glue, caulk, screws, or nails. 
         [0056]    In yet another alternative embodiment, a special nailing strip  24 T can be manufactured to have a tenon  36  extending from an outside of the nailing surface, as shown in  FIG. 13 . The size and shape of the tenon  36  will be such that it can be received in a corresponding recess  40  on the bulkhead. In this embodiment, in order to attach the bulkheads  23  to the nailing strips  24 , the tenon  36  of the nailing strips just needs to be inserted into the recesses in the bulkheads in a snap fit.

Summary:
The present invention is directed towards a series of removable bulkheads which surround and protect immovable building fixtures such as sprinkler and plumbing lines, heating and ventilation ducts, electrical and telecommunications wiring. A single bulkhead is generally comprised of a vertical panel and a horizontal panel. The bulkheads attach to preexisting ceilings and walls and provide a quick and cost effective method of concealing fixtures and allow easy access to renovate or repair the fixtures.