Chapter 23: Drywall Section

1. Introduction

Next to framing and siding, hanging drywall is one of the more “glamorous” (quick progress) volunteer activities. With the proper preparation and instruction, the drywall hanging experience can be a fulfilling one, even for those who have no previous experience. On most Habitat projects the drywall installation can be completed during 2-3 scheduled workdays.

2. Safety Issues

Stack material so that it is stable and secure. Do not ever pull the stack away from the wall as many bones have been broken by shifting stacks. Drywall is very heavy! Have volunteers carry 1 board at a time if necessary, especially up and down stairs.
Safety glasses & dust masks help prevent drywall dust from getting in your eyes & lungs, especially when working on the ceiling.
Utility knives - keep your hands out of the path of the blade. Always retract blade immediately when not in use.
Clean work areas as you go, making sure that drywall scraps aren’t underfoot, especially when working on ceilings. Instruct volunteers as to what pieces are scrap or not.

3. Prior tasks to have been completed before starting

• Framing complete and inspected (interior and exterior walls, any drywall nailers necessary, blocking for hanging upper kitchen cabinets, etc.)
• Hurricane straps installed on trusses
• HVAC rough-in complete and inspected
• Plumbing rough-in complete and inspected
• Water lines installed and tested (including stud protectors)
• Electrical rough-in complete and inspected
• Insulation and vapor barrier installed and inspected on the exterior walls (if using fiberglass insulation)
• Truss baffles installed even though the attic insulation may not have been installed
• All pre-dry wall installation air sealing tasks are complete (see Air Sealing)

4. Recommended Staff/Crew Assignments

It is suggested that approximately 15 volunteers, including 4 crew leaders, be recruited for Drywall phase. (At least one or two experienced drywallers are important to have.) Divide the crews up by distributing the experience level among the crew leaders. On workdays when there are a large number of workers assigned, they can be divided into small crews and each crew assigned to complete all the drywall installation in a particular room: ceilings, walls, closets, and window wraps. With a smaller number of workers, it may be desirable to have all the volunteers concentrate on installing the ceiling panels throughout the house, then continue with the walls in one or two rooms at a time. Assign one person to follow after the workers and sink and fix all screws that are below the surface, etc.

6. Tools/Equipment list

Tools & Equipment Needed at Each Site:
Twelve-Gauge Drop Cords (50'-100' as needed for power at site)
Heavy-duty power strips
Step Ladders (6')
2-4 Drywall “T-posts” (For supporting ceiling panels during installation)
Toe-Operated Drywall Lifters (2-3 pair)

Tools Each Drywall Crew Leader Will Need:
Measuring Tape (20'-30')
Drywall Square (4')
Keyhole Saw
Drywall Saw
Permanent Markers/Red Lumber Marking Crayon
Radius Cutter
Electric Drywall Screw Guns with Extra Bits and/or Cordless Screw Gun(s) w/ Special Drywall Screw Bits
Sureform Drywall Plane
2 Step Ladders (4'-6')
12 Gauge Drop Cords (50')
1-2 Large (29 oz.) Caulk Guns
Drywall benches

Tools Each Drywall Crew Member Will Need:
Hammer
Nail Apron
Retractable Utility Knife with extra blades
Retractable Measuring Tape (16' Minimum)
Square (Speed or Combination)
1-2 Pencils
Safety Glasses
Work Gloves
Dust mask if desired

7. Material List

Regular Drywall (typically either 4'x10' or 4'x12' sheets of ½" gypsum wall board)
Moisture-Resistant Drywall (4'x8' sheets of ½" gypsum wall board for all bathroom walls and for selected kitchen “wet walls”)
Drywall Screws (1-5/8" typical)
Drywall Nails (1-5/8" barbed typical)
Drywall Adhesive (29 oz tubes

8. Quality Checkpoints

9. Construction Drawings and Text

NOTE: The following drawings, diagrams, and text are to be used on the job site when a question arises as to methods and procedures associated with the task. The notes on the drawings have been geared toward use as a quick reference. If a more in-depth explanation is needed, please read the text description. But most importantly, consult your Habitat Site Supervisor and Construction Manager for advice as needed.

General Guidelines: Before any panels are cut, develop a plan for the ceilings and walls in each room. (The HFH staff should know) Measure the width of the room in the direction that the ceiling panels will be installed. Then measure each wall in the room. In general, make your cut in the gypsum board ¼" shorter to make it easier to install. Note: The panels must be laid out perpendicular to the ceiling joists and wall studs. Volunteers should always mark the studs on the sub-flooring (permanent black markers) and ceiling (pencil) before covering the walls with drywall. Ink should NOT be used to mark drywall or painted wood for it will always bleed through. Marking the ceiling and floor enables the crews to then mark where the studs are on the drywall, providing a guide for those charged with placing screws.

To cut a panel to the desired length, mark the dimension on the top edge of the panel and cut across the 4' face or back of the panel with a utility knife. Use a 4' drywall square as a straight edge to guide the knife. After cutting through the face of the panel, bend the panel away from the face side and cut along the crease on the back of the panel. To cut along the longer dimension of the panel, mark the desired width on the face of the panel in at least two places. Then strike a chalk line between these points and cut with a utility knife. The 4' drywall square can also be used as a straight edge to guide the knife on these cuts.

Before any panels are installed, lay out and cut holes for electrical boxes, heating vents, etc. The maximum space allowed around electrical boxes is ?", so accurate measuring and cutting is important. To properly locate a round electrical box (normally on ceilings), measure the distance from two adjacent walls (or from the edges of adjacent panels which have already been installed). Transfer these measurements to the face side of the panel to be installed, marking where the two points intersect. If a radius cutter is available, place the pivot point of the cutter at this point and cut a hole to the required diameter. The hole can also be cut with a keyhole saw after first marking for the hole with a compass or a template of the proper size (another round electrical box makes a good template). For larger holes or openings (doors, windows, attic stairs, medicine cabinets), it is best to install the panel first, then cut out the opening using a keyhole saw or a drywall saw using the edge of the frame opening as a guide for the saw.

Some hanging techniques and guidelines to be observed include the following:

Ceiling board should be hung first with all four-foot edges staggered and breaking on wood trusses or nailers (unless using truss clips at edges). Drywall Adhesive should be applied to the bottom of the truss chords before installing the board. Gaps between boards should be limited to a maximum of ?". The ceiling boards are hung first so that when the wallboard is hung, the edges of the ceiling boards are supported.

At this time, drywall board (ceiling) is to be screwed, not nailed (nails okay to tack up a board). The screw pattern for ceiling boards is 5 screws per four-foot width on each truss that is 24" on center, with 7 screws on the ends of each board. Where a ceiling panel meets an interior wall that is perpendicular to a roof truss, the principles of a “floating gypsum corner” should be adhered to. The closest screw to the wall should be about 8" away on the ceiling (and 8" down on the wallboard.) In all cases, too many screws necessitate more finishing work while too few screws or poorly positioned screws may cause sagging boards. With roof trusses at 24" on center, there is a significant span between rows of screws.

After hanging the ceiling boards, the wall boards are hung next, always in a horizontal pattern with the top tier hung first with four foot staggered seams. Maintaining a horizontal pattern throughout results in a single tape joint 4 foot off the ground that is relatively easier to finish than vertical seams. Again, the four-foot seams should be staggered. As with the ceiling boards, 5 nails or screws should be used on every width of wallboard, with 7 on each end, and maximum gaps between boards should be limited to ¼" or less. With the aid of drywall lifters, the bottom tier of boards should fit snug beneath the top tier of boards. Done properly, there ought to be about a half-inch gap between the floor and the bottom of the first horizontal tier of drywall. At no time should the bottom tier of drywall be resting on the floor. Stud cavities serving as cold air returns should be trimmed with broken metal so that no ½" gap exists once the studded wall is covered. NOTE: Care should be taken to install drywall in the closets before all the walls in a room are covered, since it may be difficult to get drywall panels into these smaller areas after the walls are done.

There should be no seams above the edges of doors and windows. Seams above windows and doors should always break approximately in the middle of the window or door opening to eliminate future cracking that will undoubtedly result if positioned at the edge. Because window openings are not to be wood cased, the two vertical and top window edges should be returned with drywall (eventually with metal corner bead applied by the drywall contractor to the edges) leaving the bottom ready for a window sill (typically wood). This method provides for a sharp, durable finish.

It is very important that volunteers understand that when placing screws into the board, the paper should not be broken. This essentially eliminates the holding power of the screw for it is the paper that holds the gypsum. Screw guns have an adjustment that allows the head of the screw to be counter-sunk just below the surface of the panel. The screws should be approximately 1/16 " below the surface. Remove ALL screws that miss a stud or are not driven in straight. Dimple the paper where screws and nails have been removed.

Most important, hanging drywall is not a race. Each crew should take as much time as it needs to do a consistent, and quality job.

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  Page last updated Saturday, May 3, 2008 at 6:40:10 PM