Installing and Finishing Drywall

Hanging drywall is a project that is well within the means of an average homeowner. Drywall is a relatively heavy material and it will be a good idea to have at least one friend available to help you with the installation. The finishing of the drywall, known as mudding and taping, is as much of an art form as it is a skill and requires plenty of practice to master. Fortunately, finishing drywall is a pretty forgiving task and allows the unskilled worker to keep reworking the job until satisfactory results are achieved.

The first step in drywall installation is figuring the amount of drywall that will be needed. This is done by calculating the total area of the space being dry walled. Add the total area of the walls and ceiling and divide by 32 (a standard 4×8 sheet of drywall measures 32 square feet). This gives you the amount of sheets to purchase. It is a good idea to purchase 5-10% more drywall than needed to account for mistakes and waste. Drywall does come in other sizes such as 12′ lengths and 5′ widths, but using these oversized sheets make it much more difficult or impossible to work with or even get into the area being dry walled.

Supplies

It is common practice to use moisture resistant drywall or “green board” for areas with high moisture such as bathrooms and concrete board such as Wonderboard or Durock should be used under ceramic tile applications such as shower or tub areas.

Mud or joint compound and tape will also be needed. Buy the pre-mixed joint compound available in 5 gallon pails at 1-2 pails per 500 sq. ft. of area being dry walled. Tape comes in 2 forms, paper tape and self adhesive, fiberglass tape. Although paper tape has its advantages, fiberglass tape is easier to use and recommended for typical DIY projects.

Metal outside corner or drywall bead will be needed at outside corners and comes in 8′ lengths. You will also need to pick up drywall screws to fasten the sheets to the wall. 1-Ã?¼” coarse thread screws will suffice. Purchase a pound of drywall nails for hard to screw areas and also for installing the drywall bead.

Tools

A drywall lift is a very handy tool for lifting drywall to the ceiling, especially if working alone, and can be rented at home improvement stores. Fashioning a lift or T using 2×4’s could be done if on a tight budget.

Other essential tools would be a battery-powered screw gun, utility knife with several spare blades, hammer, t-square and keyhole saw for cutting around electrical boxes.

For taping, you will need a 6″ and a 12″ taping knife, sandpaper and a mud trough to hold the joint compound while you are taping.

Preparation of the site

After the electrical, plumbing and framing has been inspected, a vapor barrier of plastic sheeting should be stapled over the insulation on exterior walls.

Insure that all the corner nailers that the drywall will be attached to are in place and that the framed walls create smooth, flush planes, shimming wherever necessary. Metal plates should be installed to studding where nails and screws could accidently penetrate electrical or plumbing fixtures.

Installing the drywall

Hang the ceiling sheets first so that the wall sheets help support the ceiling sheets. Screws should be spaced 8-12″ on every stud and the screws should penetrate the drywall only as far as creating a small dimple in the sheet. Driving a screw too far will cause it to “pop” through. Screw the perimeter of the shhet first to support the sheet and then fill in the field.

Moving on to the walls, it is common practice, but not necessary to start from the top down. Hang the sheets perpendicular to the floor and stagger the seams. Leave Ã?½” gap between the last sheet and the floor. Setting a scrap piece of drywall on the floor as a shim to hold up the bottom sheet is helpful.

If possible, try to use full sheets around doors and windows, cutting out the excess afterwards. This can significantly reduce installation time.

Corner bead

Next, install the corner bead at every outside corner by nailing every 6-8″ through the framing.

Taping and Mudding

Begin taping the ceiling first by centering the self-adhesive fiberglass tape over each seam. If paper tape is used, a light skim coat of compound is needed to embed the tape. Apply a light skim coat over the tape, all along each seam using the 6″ taping knife. Don’t worry about completely masking the tape at this point. Additional coats will eventually hide it.

Next, apply a light skim coat to the inside corners and embed paper tape into the corner. Then, apply a skim coat to each half of the corner, lightly covering the tape. Patience is required here, remembering that any imperfections at this point are acceptable and will be corrected later.

Next, apply a light coat of compound over the screw holes using the 6″ knife. Again, just a skim coat, enough to fill the hole.

Now move on to the walls, applying the first coat to the seams as done with the ceiling. Apply compound to the outside corners to about 3-4″ from the corner on each wall.

Allow the first coat to dry overnight and clean your tools.

2^nd Coat

After the first coat has dried, it’s time to apply the second coat, starting with the ceiling. Using the larger knife, apply a liberal amount of compound to the seam and pull the compound along the seam in large strokes, applying more pressure to the outside edge of the knife and feathering the compound out across the seam. This coat should hide the tape.

Next recoat the screw holes, feathering out the compound.

Move on to the corners and walls using the same basic strategy. The idea is to apply the second coat over a larger area and feathering out the edges. The smoother the finish at this point, the less sanding will be needed later. Patience is key.

Allow the second coat to dry and clean your tools.

3^rd coat

This coat requires the least amount of mud, but the greatest amount of finesse and artistry. Take your taping knife and run it along all the seams, removing any bumps in the dried compound. Starting again at the ceiling, apply a light, skim coat to the seam, filling in any lines or recessions in the dried compound.

Next, apply a final coat to the screw holes, wall seams and corners.

Allow the final coat to dry overnight.

Sanding

Sanding is a very messy job and a dust mask is highly recommended. The amount of sanding will depend on how well the taping job is. A first-time DIY will undoubtedly have some sanding to do.

Using a fine sandpaper, simply sand over the seams, using even as possible strokes and blending the compound to the wall surface. Try to avoid excessive sanding as this will damage the drywall surface. After sanding , clean all dust and the wall is ready for painting.

References:

Mark Donovan, Installing Drywall: Mudding and Taping, www.superhomeideas.com