Raised Access Flooring

A raised access flooring provides an elevated structural floor above a solid substrate (often a concrete slab) to create a hidden void for the passage of mechanical and electrical services. Raised floors are widely used in modern office buildings, and in specialized areas such as command centers, Information technology data centers and computer rooms, where there is a requirement to route mechanical services and cables, wiring, and electrical supply. Such flooring can be installed at varying heights from 2 inches (51 mm) to heights above 4 feet (1,200 mm) to suit services that may be accommodated beneath. Additional structural support and lighting are often provided when a floor is raised enough for a person to crawl or even walk beneath. Raised access flooring is a building solution commonly employed in applications where an owner or leaseholder would like to provide a means of routing building communication, electrical or climate control services in a way that provides for a clean aesthetic and facilitates easy reconfiguration. Raised access flooring provides a simple, rapidly-installed and flexible means of achieving this goal for a reasonable cost.

PRODUCT FEATURES:

❖ This type of floor system tackles the problem of shear transfer across the diaphragm

❖ It leads to reduction in the cost of construction in high seismic regions

❖ Raised floor system could serve as a high thermal mass base material for radiant heat systems which are distributed by hot air or hot water. So, Heating and cooling a building with a raised flooring system is more efficient

❖ The concrete surface can be finished as a final floor finish as desired by sealing, polishing, stamping, or staining. Consequently, the extra cost of covering used for covering floors will no longer be needed

❖ Acoustic isolation is another advantage offered by a raised floor system.

❖ In high wind threat areas, elevated floor system will improve the lateral resistance and durability of multistory building especially when it combined with concrete roof system

❖ Fire is suppressed from floor to floor

❖ Ease of reconfiguration and easy access -

❖ Energy and cost saving

❖ Occupant health and comfort

❖ Design flexibility

❖ High potential for customization

INSTALLATION METHOD:

1. STEP 1. Check the room dimensions and configuration against approved drawings.

● Using a builder's transit or laser, shoot in the areas to receive access floor to determine how much variation there is in the level of the subfloor within the room and at the termination points, such as elevator and door sills and concrete ledges. If the floor cannot be installed per your drawings, notify the general contractor superintendent for agreement on corrective action

1. Step 2. Determine Starting Points

● Find the starting point in the room as shown on the drawings. Seek approval to change the starting point if cut panels at the perimeter will be too small to allow proper support. Recommended minimum size of the cut panels for proper support is 6 inches wide.

1. Step 3. Layout Grid

● Having established the proper starting point, lay out two chalk lines at right angles to make sure the room is square. See figure 1 for exact procedure. Chalk lines must be used as control lines for installing the access floor. The reason for laying chalk lines for installing the access floor. The reason for laying chalk lines rather than just measuring from the walls is that the walls are not always square. The chalk line system gives a square reference point. Be careful to keep the access floor square at all times during installation.

1. Step 4. Check Control Lines

● Chalk the two control lines and spread pedestal assemblies in an area approximately 48 feet x 24 feet, making sure to start at the approved starting point

1. Step 5. Target Finished Floor Height

● Using a laser or transit, shoot in a pedestal assembly to the proper FFH every 8 or 10 feet in both directions (depending on the length of your leveling bar.) By spanning two pedestals at proper FFH with the leveling bar, adjust all the pedestals in between to the bottom surface of the bar. As you adjust each pedestal assembly, center it on the two-foot marks permanently marked on the bar.

1. Step 6. Glue Pedestals

● Glue each pedestal base in the spread area to the subfloor. Using a spatula type device, tilt up the base plate without changing its location and apply adhesive to the bottom of the base plate.

1. Step 7. Bolt Stringers

● stringers are a part of the system, bolt them to the pedestal heads beginning at the starting point.

1. Step 8. Lay Panels in one Direction

● Beginning again at the start point, lay four rows of panels along the longest wall. Check to see that you are staying on control lines, and that panels do not rock

1. Step 9. Check for rocking panels

● If a panel rocks diagonally when placed in the system, turn it one quarter (90°) turn and check it again. If the panel continues to rock when rotated, some debris may be between the panel bottom and the pedestal head or stringer. Also check to make sure the pedestal is not tilted, stringers are properly seated and that panel edges are flush. If the panel still rocks, set it aside to be used as a perimeter cut panel. The pedestals should not be adjusted unless three or four panels supported on it are rocking. At this point, make a minor elevation adjustment to the pedestal.

● When installing carpeted panels, the carpet grain direction must be controlled. Each panel has an arrow on the bottom indicating proper carpet grain. All panels must be installed with the grain in the same direction. Therefore, they cannot be turned to adjust for rockers. The panel can be bumped or the pedestal assemblies adjusted. It may require two or three pedestals in a row to be adjusted.

1. Step 10. Lay panels in opposite direction

● After laying the first four rows of panels along the long wall, begin again at the starting point and lay four rows of panels perpendicular to the first rows. Follow the same previous steps (8 through 9) for laying panels and be sure to follow the control lines. If you do not stay on the control lines, the floor will not be square and your grid lines will not be straight. After laying in the ELL section, check and recheck to be sure it is square. When you are certain the ELLis square, continue to install rows until the ELL becomes a rectangle or square. While you are laying panels in this area, you should have someone spreading, shooting, leveling and preparing the next adjacent area for panels..

1. Step 11. Align Grid

● After the first section of a floor is installed, check to see that all the grid lines are straight. If the grid is not square, you can make them square by bumping the rows of the installed panel with your foot. If this fails, take up every third or fourth row of panels and tap the bases in the direction of the panels that have to be moved. All grid lines should be straight before cutting in the perimeter panels.

1. Step 12. Proceed with next row

● After installing the first section of A/F, only one chalked control line along the long wall needs to be used for the remainder of the floor. The initial section of floor normally dictates the squareness and location of the rest of the floor. However, it is possible in a long room to allow a curve to develop in small increments in the grid. Therefore, a dry line should be kept stretched along the short wall until at least a four-panel-wide section of the floor is installed the entire length of the room.

● In setting this dry line, secure one end at the starting point on the grid line between the first two panels. Raise the line about one inch off the panel, then stretch the line to the other end of the floor and do the same there. The line should not override the panel edges.

INSTALLATION MATERIALS:

❖ Diffuser

❖ GROMMET

❖ Electrical Box

❖ Access floor

❖ Panel lifter

❖ Skirting

❖ Wedge

❖ Pedestal fixing adhesive

❖ Ramps

❖ Perforated panel

❖ Stringers

❖ edge trim,

❖ grounding clips,

❖ stringers, gaskets