PlasterCast™ GRG Column Cover Installation Instructions
Prior to beginning any installation, be sure you have a set of the most current shop drawings on the job site. Review and understand all information on these drawings prior to beginning installation. Inventory the GRG pieces you have received and compare to the shop drawings. Confirm quantities and dimensional correctness prior to beginning installation. If you have any questions, please call your Melton Classics representative at 800-963-3060.
Prior to beginning installation, unwrap or uncrate a random sampling of pieces. Column covers may or may not be shipped in matching pairs. If they are shipped in matching pairs, the matching nomenclature will be clearly detailed on the Bill of Lading or Packing Slip, and the pieces themselves. In theory, all pieces of a particular type should match. Sometimes, in shipping, handling and storage some pieces can become distorted. These distortions can usually be corrected with a fairly small amount of effort.
Inspect the insides of the pieces for any protrusions or obstructions that will interfere with matching, mating or attachment of pieces. Use a belt sander, rasp, saw, or grinder for removal.
SINGLE HIGH INSTALLATION
- GRG column covers should be installed using the supplied alignment clips. These clips are designed to promote an accurate matching of column cover halves. However, alignment clips do not guarantee an optimum match. Some shimming and grinding may still be required.
- Begin by positioning the first half of the column cover. Mechanically attach metal of pressure treated wood clips to the structure at both the top and bottom of the column cover. The clips should be set immediately behind the GRG at the seams and the midpoint of the piece. Pre-drill pilot holes through the face of the column cover into the clips. Attach the GRG to the clips with drywall screws and countersink the screw heads.
- Once the first half of the column cover is installed, begin installing the “alignment” clips. Clips should be installed near the top and bottom and approximately 18″ o.c. along both sides of the initial half. Alternate the orientation of the clips. Clips should be anchored with drywall screws and screw heads should be countersunk.
- Loose fit the second half of the column cover to ensure proper fit and alignment. Some shimming or grinding on the inside of the second half may be required to obtain the optimum match. It may be necessary to use a band clamp or webbing to pull the two column halves together for the snuggest fit.
- Prior to final installation of the second half of the column cover, apply a continuous bead of urethane adhesive along the full length of both edges of the first half of the column cover. Final fit the second half of the column cover and secure to the alignment clips on one side of the first half only. Shim the other side as necessary to obtain the optimum match. Secure the alignment clips. Counter sink the screw heads.
- Sand or rasp any high spots along the seam lines so that the sides are flush with each other.
DOUBLE HIGH INSTALLATION
- The same basic process outlined above is applicable. However, there will be a few minor but important modifications.
- The tops of the lower column cover pieces will have 2″ wide horizontal flanges and the bottoms of the upper column cover pieces will have 2″ wide horizontal flanges. These flanges are for use in stacking the pieces.
- Follow steps 1-6 in the SINGLE HIGH INSTALLATION. Install horizontal kickers anchored to the center structural column. These kickers should fit snugly underneath the 2″ wide top flange on the lower pieces. The kickers and their attachments to the center structural column should be sized to support the dead load of the upper column pieces.
- Place a bead of urethane based adhesive on the top of the 2″ wide top flange on the lower pieces. Install both upper column covers pieces by following steps 1-6 in the SINGLE HIGH INSTALLATION.
PATCHING AND JOINT FINISHING
- Prior to patching or finishing joints the area of the column cover to be finished should be wiped with a damp sponge. Allow the moisture to be absorbed by the column cover. Patching and finishing can be accomplished with gypsum joint compound or casting plaster.
- Generally, column covers with flattened spots at the joints (or 1/8″ X 1-1/2″ recesses) are finished with joint compound. Either paper tape or fiberglass tape may be used. It is helpful to curve the blade to match the curvature of the column cover. As with gypsum board, three coats will generally be required.
- Column covers with no flat spots at the joints (or elements of column covers with no flat spots at the joints such as decorative capitals or bases) are generally finished with casting plaster. Finishing with plaster can generally be accomplished with one or two coats.
- Patching dents or dings can be done with either joint compound or casting plaster. Again, it is advisable to wipe the area to be finished with a damp sponge prior to applying the joint compound or plaster.
- When the column covers are located in areas of either critical artificial or natural lighting, a level 5 finish (per ASTM C840) must be applied by the finisher.
- When the column covers are to be decorated with a paint containing sheen a level 5 finish (per ASTM C840) must be applied by the finisher.
- All column covers must be primed with a primer prior to receiving decoration. More than one coat of primer may be required. Sanding after application of primer may be required.
- GRG Column covers should be stored in a dry location away from dirt and mud.
- If the column covers are delivered in wooden crates or frames, leave them in their containers until you are ready to begin installation.
- Store containers on level ground or pavement.
- If the column covers are delivered loose, store in a completely horizontal position or as dose to a vertical position as possible.
- If stored in a horizontal position the pieces should be stored open side down. Pieces should not be stacked on top of each other. In fact, any form of applied weight to the top side will cause the pieces to spring open, or cup closed.
- If stored in a vertical position the pieces should be adequately braced to prevent them from toppling over.