Putting drywall on a cement wall typically involves creating a framework or system to attach the drywall to, allowing for a flat surface and often space for insulation and moisture management. One common and effective method uses metal furring channels, also known as "hat channels."
Why Use Furring Channels on Concrete?
Directly attaching drywall to concrete is generally not recommended due to potential moisture issues and the unevenness of concrete surfaces. Using furring channels provides several benefits:
- Creates a Flat Plane: Concrete walls are often uneven. Furring channels can be shimmed or adjusted to create a perfectly plumb and flat surface for the drywall.
- Allows for Insulation: The space between the concrete wall and the drywall (created by the channels) can be filled with insulation for energy efficiency.
- Manages Moisture: This method allows for a vapor barrier to be installed between the concrete and the channels, helping to prevent moisture transfer to the drywall.
- Provides a Secure Attachment Point: Drywall screws can easily attach to the metal channels.
Attaching Hat Channels to Your Cement Wall
The process involves preparing the wall, laying out the channels, and then securely fastening them.
Preparation is Key
Before starting, ensure the cement wall is clean, dry, and free of loose debris. Address any major cracks or moisture problems. Consider applying a concrete sealer or vapor barrier if moisture is a concern.
Layout and Installation
- Mark Reference Lines: Use a level and a long straightedge to draw vertical lines on the wall. These lines indicate where the center of your hat channels will be placed. Draw a plumb line to make sure you've spaced the hat channels properly for the size of drywall and insulation you're using. The standard spacing for hat channels when using 1/2" drywall is typically 24 inches on center, aligning with the standard width of drywall sheets (4 feet).
- Position the Channels: Hold the first hat channel along its plumb line. Use shims behind the channel if necessary to ensure it is plumb and aligned with any channels it will meet at corners or edges.
- Fasten the Channels: This is where concrete fasteners come in. You will need a way to drive fasteners into the concrete. Use concrete nails and a concrete-nail gun to attach the hat channels to the wall. Drive fasteners through the channel and into the concrete wall. Drive three concrete nails, spaced at even intervals, through each side of each hat channel. This provides a robust and stable attachment point. Repeat for all vertical channels.
- Install Horizontal Channels (if needed): Depending on the wall height and layout, you might also install horizontal channels or bridging between the vertical channels for added stability, especially at the top and bottom plates.
- Frame Openings: Build simple frames using hat channels or metal studs around windows, doors, and other openings to provide solid attachment points for drywall edges.
Summary Table: Attaching Hat Channels
| Step | Action | Notes |
|---|---|---|
| Layout | Draw plumb lines for channel centers. | Standard spacing: 24" on center. |
| Position | Hold channel in place, adjust for plumb/flatness using shims. | Ensure alignment with other channels. |
| Fasten | Use concrete nails and a concrete-nail gun to attach. | Drive three concrete nails through each side of each hat channel. |
| Horizontal/Frame | Install horizontal channels or frame openings as needed. | Provides rigidity and attachment points. |
Once all the hat channels are securely attached and plumb, you have a stable framework ready for insulation (if desired) and then the drywall sheets.
Installing Drywall
With the hat channels in place, installing the drywall is similar to hanging drywall on a standard wall frame:
- Add Insulation (Optional): If you planned for insulation, fit batts or rigid foam insulation into the cavities between the hat channels.
- Attach Drywall Sheets: Lift the drywall sheets into place horizontally or vertically.
- Screw to Channels: Drive drywall screws through the drywall and into the metal hat channels. Use fine-thread drywall screws designed for metal studs. Ensure screws are slightly countersunk below the surface but don't break the paper face.
- Cut Openings: Cut out openings for electrical boxes, windows, and doors.
- Finish Joints: Apply joint tape and multiple coats of joint compound (mud) over the seams and screw heads. Sand smooth between coats.
- Prime and Paint: Once the mud is dry and sanded smooth, prime the entire surface and then paint.
By using hat channels and concrete fasteners as described, you can successfully install drywall over a concrete wall, creating a finished, insulated, and ready-to-paint surface.
