Introduction
Furring strips create a new, flat surface for hanging drywall over plaster.
This method helps prevent hollow spots by giving you solid backing and a frame to fasten into. Check your local rules and manufacturer guidelines for spacing and fastener choices.
Plan your layout, level the strips, and avoid compressing the plaster when you attach them. Use appropriate fasteners per label instructions, and verify solid anchoring before proceeding. If in doubt, double-check with the product label or local code requirements.
Key takeaways
- Assess plaster for hairline cracks, moisture, and sound hollow while tapping gently.
- Use furring strips where plaster is uneven or brittle to prevent hollow spots.
- Prepare plaster with appropriate scoring or skim coat to create drywall-ready surface.
- Secure furring strips level with a straightedge; wear eye protection to prevent debris.
- Adhesive limits and risk: test adhesion on small area before full drywall application.
- Conduct visual checks and tap tests after install; address hollow spots immediately.
Table of Contents
- Introduction
- Key takeaways
- Assessing the Existing Plaster Wall
- Materials, Specs and Tools Checklist
- Preparing Plaster for Drywall Installation
- Installing Furring Strips: Step-by-Step Best Practices
- Adhesive Installation: Techniques, Limits and Risk Management
- How Hollow Spots Form and How to Prevent Them
- Visual Checkpoints and Testing for Solid Attachment
- Finishing, Troubleshooting and Code/Cost Considerations
- Conclusion
- FAQ
Assessing the Existing Plaster Wall
Start by examining the plaster for cracks, cracks that expand with movement, or loose sections that rattle when tapped. Look at the underlying substrate to identify lath, masonry, or gypsum board behind the plaster. Check for hollow areas or signs of moisture damage that could affect fastening options.
Decide between furring strips and heavy adhesive based on what the wall can support and how sound the structure is. Verify the wall’s condition by reading labels, manufacturer instructions, or local building notes before choosing a method. If in doubt, consult the product data sheets and applicable codes for recommended practices.
Signs plaster is suitable for adhesives
The first step in deciding whether to use adhesives for hanging drywall over existing plaster is to assess the condition of your walls. Adhesives work best on solid, stable surfaces with good adhesion.
Look for these signs that your plaster might be suitable for adhesives:
Smooth surface: If the plaster has a smooth, even surface without deep cracks or holes, it’s likely to provide good adhesion.
No loose areas: Tap the wall with a knuckle or use a taping knife to check for hollow spots. If the sound is solid and there are no loose pieces, adhesives could work.
Limited patching needed: If you only need to do minor patching, adhesives can be a good option. However, if extensive repairs are required, consider using furring strips instead.
Signs you should use furring strips instead
While adhesives can work well in some cases, there are situations where using furring strips is a safer and more effective option. Here’s what to look for:
Loose plaster: If the plaster feels loose or crumbles easily when touched, it’s not suitable for adhesives. Furring strips will provide a solid base for your drywall.
Uneven surfaces: Deep cracks, holes, or other uneven areas can prevent adhesives from bonding properly. In these cases, furring strips can create a smooth surface for hanging drywall.
Deep profiles or hidden cavities: If the plaster has deep profiles (like textured or patterned walls) or you suspect there are hidden cavities behind the plaster, use furring strips to provide a stable surface and prevent hollow spots.
Materials, Specs and Tools Checklist
Create a builder-friendly list of required materials, including fasteners, spacers, and any furring strips, plus the drywall type and thickness you’ll install. Gather hand tools and a few power tools you’ll need for layout, leveling, and anchoring. Have a measuring tape, square, level, and marking tools ready for accurate placement.
Check material specs and standards on labels or data sheets before you buy. Look for compatibility with plaster walls, including weight limits, moisture tolerance, andEdge/face finish requirements. If instructions vary by product, follow the manufacturer guidance and local code rules for installation parameters.
Furring strips, fasteners and backing materials
Use this checklist before you start installing furring strips to ensure you have the right materials and that they’re compatible with your substrate.
- Check furring strip material: Verify strips are made of pressure-treated lumber (for exterior use) or CDX plywood (for interior use).
- Verify strip width: Ensure they’re at least 1″ wide to provide adequate support for your cladding.
- Confirm strip length: Measure and cut strips to match the height of your wall, plus an extra 2-3″ for overhang at the top.
- Check fasteners: Use corrosion-resistant screws or nails (for exterior) or drywall screws (for interior).
- Verify fastener length: Screws/nails should be long enough to penetrate the furring strip and at least 1″ into the substrate. Check manufacturer recommendations.
- Check substrate compatibility: Ensure your fasteners are suitable for the substrate (e.g., concrete, wood, metal).
- Verify backing material (if needed): If using a backing material like foam board or rigid insulation, ensure it’s compatible with your cladding and substrate.
- Check local codes: Confirm all materials comply with local building codes and manufacturer recommendations.
Quick rule: Always double-check that your fasteners are long enough to penetrate both the furring strip and the substrate. Skipping this can lead to inadequate support, cladding failure, and costly rework.
Adhesives, tapes and drywall materials
Use this checklist before starting your drywall installation to ensure you have the right materials for a smooth and durable finish.
- Drywall Screws: Check length (usually 1-1/4″ or 2″) and head type (countersunk) to match stud spacing. Wrong size can cause drywall sagging or popping.
- Drywall Joint Tape: Verify paper width (3/4″, 1-1/4″, or 2″) matches joint width for a seamless finish. Too narrow can lead to cracking, too wide wastes material.
- Joint Compound: Check consistency and type (lightweight, all-purpose, or setting-type) based on job requirements. Wrong compound can result in weak joints or difficult sanding.
- Setting-Type Compound: If using, ensure it’s the correct type for your climate to prevent premature drying or excessive shrinkage.
- Drywall Primer: Confirm it’s suitable for your paint and drywall type. Skipping primer can cause paint absorption issues and uneven finish.
- Corner Bead: Check length, width, and material (metal or vinyl) to match your job needs. Incorrect corner bead can result in damaged corners during painting.
- Drywall Boards: Inspect for damage, correct size (4′ x 8′, 4′ x 10′, or 4′ x 12′), and appropriate drywall type (regular, moisture-resistant, or fire-resistant). Damaged boards can cause costly rework.
- Adhesive for Backing Materials: If using, ensure it’s compatible with your backing material and job conditions. Wrong adhesive can lead to poor adhesion and backing failure.
Quick rule: Always check product labels and manufacturer instructions before starting any drywall task to avoid costly mistakes and rework.
Preparing Plaster for Drywall Installation
Secure any loose plaster with proper backing or removal if needed, so the surface won’t move under fasteners. Level high spots and fill obvious gaps to create a consistent plane for drywall. Address moisture or mold by treating affected areas and ensuring surfaces are dry before proceeding.
Mark any hidden services or studs behind the plaster so you don’t damage them during fastening. Clear debris and dust from the wall to improve adhesion and screw purchase. Consider a moisture check if the room has a history of dampness and follow through with remediation if needed.
Repairing loose or damaged plaster and lath
Before you start hanging drywall, it’s crucial to ensure your existing plaster wall is in good shape. Here’s how:
Loose Plaster: Use a utility knife to score around the loose area, then carefully cut out the damaged section. Apply joint compound to the back of a new piece of drywall or plaster patch, press it into place, and let it dry.
Damaged Lath: Inspect your lath (the wooden strips behind the plaster). If they’re rotten or missing, you’ll need to replace them. Cut out damaged sections with a sawzall, then install new lath using screws or nails.
Surface cleaning, priming and moisture checks
Preparing the plaster surface is key for a successful drywall installation. Here’s how:
First, clean the surface with a damp cloth to remove any dirt or dust. Let it dry completely.
Next, check for moisture issues. Use a moisture meter to test the wall. If you find high moisture levels, address the source (like leaks) before proceeding.
Finally, apply a coat of primer to seal the surface and improve adhesion. Let it dry according to the manufacturer’s instructions.
Installing Furring Strips: Step-by-Step Best Practices
Plan the layout of the furring strips to run plumb and level, prioritizing straight lines that give you a true plane. Establish a leveling strategy that accounts for wall irregularities and ensures consistent screw lines. Follow a logical fastening sequence so each strip is secure before the next is attached.
Attach strips in a methodical order to minimize gaps and unevenness, and use appropriate fasteners for the substrate you’re anchoring into. Maintain proper spacing and confirm the surface remains square as you proceed. Always verify that the strips are supported and free from movement before hanging drywall.
Step-by-Step Installation Process
The following steps guide you through installing furring strips, ensuring a solid base for your drywall.
- Preparation: Ensure the area is clear and safe. Gather tools – tape measure, pencil, level, saw, hammer or drill, and furring strips.
- Measure and mark: Determine strip spacing (usually 16″ or 24″) and mark the wall accordingly.
- Cut strips to size: Measure and cut strips to fit your wall’s height. Leave some overlap at the top for ceiling attachment.
- Attach the first strip: Start from a corner, level the bottom of the strip, and secure it with screws or nails every 12″-16″.
- Install subsequent strips: Continue along the marks, ensuring each strip is level and properly spaced. Use shims if needed to maintain consistency.
- Check for level: After each strip, double-check it’s level before moving on. Adjust as necessary.
- Attach ceiling strips: Once all wall strips are up, attach strips to the ceiling, overlapping the wall strips.
- Final check and cleanup: Inspect your work, ensure all strips are secure and level. Clean up any debris.
Layout, Level and Shim Strategies
Establishing a consistent plane for your drywall starts with proper layout and leveling of furring strips. Here’s how:
Start by finding the highest point on your wall. This will be your reference point for leveling.
Use a 4-foot or longer level to ensure accuracy. Place it on the strip, and if necessary, use shims behind the strip at the low end to bring it level with the high point you found earlier.
Shim as needed to maintain a consistent plane across all strips. This ensures your drywall sheets will lie flat and create even joints.
Fastening to Different Substrates (Masonry, Lath, Solid Plaster)
Furring strips need to be securely fastened to the substrate. Here’s how to do it right:
Masonry: Use masonry screws or anchors. Drill pilot holes and secure strips every 12″-16″.
Lath: Screw through the lath into the studs behind, if possible. If not, use drywall screws directly into the lath.
Solid Plaster: Use plasterboard screws or drywall screws. Ensure they’re long enough to penetrate at least 1″ into the substrate. Always check for hidden obstacles before drilling or screwing.