Remodeling Kitchens: Drywall and Soffits

New drywall is necessary anytime new framing or plumbing goes in. It's always better to get that taken care of before you frame in any new soffits (unless the soffits go up against finished walls and ceilings).

That's because building codes usually require that soffits be closed off from the rest of the framing since any fires that started in the soffits could otherwise spread quickly into the wall framing and ignite the rest of the house. A layer of drywall effectively closes them off and presents the necessary firestop.

There are other firestopping options available as well when you build a soffit. Check with your local building officials for the method most appropriate to your situation.

Proper Drywall Backing

Before hanging the drywall, it's critical to check all the exposed framing, especially at the corners and where walls meet the ceiling to make sure there's sufficient backing for securing the drywall panels—at least 3/4" of solid framing to drive screws or nails into.

Usually that just requires some lengths of 2x4 blocking laid in at any gaps and secured to the existing framing. But, in some areas local codes may also require horizontal blocking at the seams in the exterior sheathing of new construction and many remodel situations.

Insulation & Vapor Barrier

If any exterior wall framing is exposed, you'll have to insulate properly between the studs and around any windows/doors and cover the insulation with a vapor barrier.

Typically R-19 insulation batts are used to fill the stud cavities in a remodeling project. They're sized to fit snugly between studs spaced 16 inches on center.

Personal comfort has been an issue for anyone installing fiberglass batts, but that's no problem if you wear gloves, long sleeves, protective eyewear and proper respirators. And there are now insulating batts available which are encased in plastic and made with a less irritating material known as Miraflex, made by Owens Corning. (See Insulation for more information.)

There are also special vapor barrier materials available that staple over the insulation and framing. Overlap the seams and seal them with tape so moisture from inside the house doesn't seep into the insulation.

Tips on Hanging Drywall

Pros usually hang drywall on the ceiling first, so the panels on the walls snug up under the ends of the ceiling panels.

Start in a corner with the long side of the first panel running perpendicular to the joists or studs.

Use either nails or screws, but tap the fasteners in at the corners before you raise the panels so you can position the panel with one hand and drive them in quickly with a hammer or screwgun using the other hand.

Rent a drywall lift to raise the panels up, especially if you're working alone.

Be sure to "dimple" each fastener, burying it slightly below the surface of the drywall without breaking the paper. That way, the joint compound applied later to hide the fastener heads can be sanded off smooth and flush with the surface.

Snap chalklines on each panel to show where the joists or studs go. Otherwise, it's very easy to miss the framing in the middle of the panels.

Don't let the butt joints at the short ends of the panels fall on the same joists or studs from row to row. Otherwise, you'll end up with a noticeable ridge where the joint compound builds up (the ends are not tapered like the long edges) and risk a long crack appearing if the panels flex at any point.

To make a long, straight drywall cut, score the front side of the panel by running a utility knife along a drywall T-square, snap the end of the panel away from the scored line to break the gypsum and then cut the paper backing at the break line to finish the cut.

Use a drywall saw or keyhole saw for shorter cuts or to cut pieces after they've been secured (like over a door/window opening or an outside corner).

To cut holes in a panel for electrical or plumbing fixtures:

• Measure vertically and horizontally to the fixture from a point on the wall that'll match one of the corners of the panel.
  
• Transfer those measurements to front of the panel and mark the outline of the object (to all four corners for a rectangular box, to the centerpoint for a round object). Use a compass to make circles.
  
• Punch through the waste area with a keyhole saw and cut along the outline.
  
• Test fit the panel and trim the hole as needed with a drywall rasp.

Framing Soffits

Once the drywall is in place, any new soffits can be framed and covered with drywall also. Their usual function is to fill in the open spaces between the ceiling and the tops of the wall cabinets, but they can also be used to hide new plumbing pipes if those are roughed-in outside the wall.

They're typically about 13" wide and 7" or 8" high (with 8' ceilings and 36" high wall cabinets).

• The front is usually built by suspending a short wall from the ceiling, and the bottom is framed between that and the wall.
  
• A pair of 2x4 nailing strips are secured first, one to the ceiling and one to the wall but running parallel to each other.
  
• A 2x2 "ladder"-type wall is built on the floor for the front of the soffit, consisting of 2x2 plates, 2x2 plates matching the lengt../store/videos of the nailing strips, and 2x2 studs equal to the soffit height minus 3" for the thickness of the plates.
  
• The studs are nailed between the plates every 16" for proper drywall backing, and the studs are so short the framing ends up looking like a ladder.
  
• The top of the framing ladder is set flush to the ceiling, snug against the edge of the nailing strip, and it's nailed or screwed into it to secure it solidly. (Using screws is often preferred because there's less stress on the existing structure.)
  
• 2x2 "lookouts" (short, horizontal framing members) are cut to frame the bottom of the soffit, extending from the bottom of the nailing strip on the wall to the bottom of the front of the soffit, and they're secured by nailing or screwing up through their ends into the nailing strip and the front of the soffit.
  
• The soffit framing can then be covered with drywall.

Finishing Drywall Joints

You can usually figure on three separate applications of joint compound to finish the new drywall joints.

First Application:

Fill each joint with compound, feather it out a couple inches each way and embed fiberglass mesh tape or paper tape in it. Also cover the screw and nailheads, filling the dimples and scraping away the excess. Let the first application dry overnight, unless you're using a quick dry formula—then follow package directions.

Second Application:

Before starting, use a drywall knife to scrape off any ridges left on the first application. Then spread more joint compound over the first application, spreading the compound thinly beyond the dried edges an inch or so. You're basic goal is to hide the inevitable build-up of compound by feathering it out across the surface, while filling any gaps left by the first application. Let the second application dry.

Third Application:

Scrape off any new ridges left after the second application, and then spread out your third layer of compound, feathering it even further this time. Let that application dry, sand it with a drywall screen and coat the surface with a good primer-sealer. Then you're ready for cabinets.

For more information please visit our Finishing Drywall Section