Installation Instructions for Interior Door Slabs

Introduction

Thank you for selecting Lowe's® RELIABILT products. These instructions provide recommended installation guidance for all types of Wood Interior Door Slabs, including Molded, Flush, Premium Composite, and Stile and Rail. Thoroughly read these instructions before beginning. While designed for most existing applications, modifications may be necessary due to specific site conditions. Any changes made are at the installer's risk. For installations requiring professional expertise, consult a building professional.

Important Information

Building Codes

Consult your local building code official for applicable building codes and regulations. Local building code requirements supersede these installation instructions.

Installer Note

Provide a copy of these instructions to the building owner. By installing this product, you acknowledge the terms and conditions of the limited warranty as part of the terms of the sale.

Glossary

Head Jamb

The horizontal jamb across the top of the opening.

Hinge

Metal component that attaches the slab to the jamb and allows the slab to swing open and closed.

Hinge Jamb

The side jamb the hinges are mounted in.

Hinge Leaves

The flat parts of the hinge that mount to the jamb and slab.

Hinge Pin

Pin that holds the hinge leaves together and allows them to pivot.

Hinge Route

Mortise in the jamb and slab the same profile as the corresponding hinge leaf.

Frame

A frame consists of a hinge jamb, head jamb, and strike jamb. Once installed, the door slab is hung inside the frame.

Panel

Component of the slab filling the spaces between the stiles and rails.

Pilot Hole

A drilled hole that is no larger than the body of the screw (minus the threads).

Rail

Horizontal members of the door slab.

Slab

The operating part of the door assembly that swings open and closed inside a frame.

Stile

Vertical members of the door slab.

Stop

Component fixed to the inside of the jamb that the slab closes against.

Strike Jamb

The side jamb that contains the latch strike to hold the slab closed.

Please allow sufficient time to properly prepare the opening, install the slab, and ensure its proper operation.

Safety, Storage and Handling, Finishing

Safety Precautions

• Read and fully understand all manufacturer's instructions before beginning. Failure to follow instructions may result in denial of warranty claims.
• Use safe lifting techniques.
• Wear protective gear (e.g., safety glasses ?, gloves ?, ear protection).
• Operate hand/power tools safely and follow manufacturer's instructions.
• Heed material manufacturer's handling and application instructions.
• If disturbing existing paint, take precautions for lead paint (common before 1979). Refer to EPA or Consumer Product Safety Commission for information.

⚠️ WARNING: Drilling, sawing, sanding, or machining wood products can expose you to wood dust, a substance known to the State of California to cause cancer. Avoid inhaling wood dust or use a dust mask or other safeguards. For more information, visit www.P65Warnings.ca.gov/wood.

Storage and Handling

• Deliver doors to the building site after plaster, drywall, and/or concrete are dry.
• If storing doors on-site before installation, seal the top, bottom, and sides.
• Hollow core doors may warp more than solid core doors. When stacking, keep the top door covered with plywood or cardboard to prevent warping.
• Keep doors away from direct sunlight and sources of extreme heat, cold, or humidity.
• Store flat on a level surface in a clean, dry, well-ventilated building. Protect from dirt, water, and abuse. Allow air circulation. Cover the top door with a moisture barrier. Do not lean doors vertically against a wall or structure.
• Handle doors with clean hands or clean gloves.
• Lift and carry doors; do not drag them across one another.
• Avoid abnormal or sudden variations in heat, dryness, or humidity. Do not expose to direct sunlight. Recommended conditions: 25%-55% RH and 50°F-90°F (10°C-32°C).
• Store doors at least 10 feet away from any heat source to prevent uneven drying, warping, splitting, or bowing.
• Acclimate doors to prevailing humidity and temperature for at least 48 hours before hanging (72 hours in extreme temperatures).

NOTICE: An inked stamp with "<LB, LB>" or "<LB>" indicates the lock block location. The arrow next to the LB indicates the lock block. If present, cover with tape, a clear coating, or regenerate after sealing.

Finishing

• Set up a clean, well-lighted, dust-free, well-ventilated finishing area, out of direct sunlight and in a climate-controlled environment. Cover areas subject to paint or stain exposure.
• Acclimate doors to the installation environment for a minimum of 48 hours under normal room conditions (72 hours in extreme weather). Avoid finishing immediately after rain or damp weather, or during high humidity periods. In very dry conditions, finish immediately after removing wrapping. Ensure adequate airflow around all surfaces. Follow paint/stain manufacturer's instructions for temperature and humidity recommendations.
• Remove all hardware before finishing.
• When using water-based paint, apply in light coats in a warm, dry environment. Do not reduce paint beyond manufacturer recommendations. Applying water-based paint in cold/damp conditions or in heavy coats can cause the paint to take longer to dry, penetrate the board, and raise the grain. Satin or semi-gloss finishes are recommended.

⚠️ WARNING: Distortions like warping, bowing, and waviness can result from incorrect topcoats, improper finishing techniques, or finishing conditions (e.g., watered-down paints, high humidity, excessive paint application, or lack of acclimation).

For additional details, reference Window & Door Manufacturers Association guidelines on storing, handling, finishing, and installing wood doors.

Materials and Tools

Needed Materials

• Hinges
• Wood screws (3/4" minimum through hinges into slab and frame; 1-2 1/2" through top two hinges into framing for solid core, premium composite, stile and rail doors)
• Wood putty/spackle
• Lock set and template
• Finishing supplies
• Masking tape (for trimming)
• 150-280 grit sandpaper

Needed Tools

• Safety glasses ?
• Screwdrivers ?
• Pencil ✏️
• Chisel or router ?️
• Drill with bits and hole saws
• Tape measure ?
• Level ?
• Finishing tools (paint brushes, roller, spray equipment, masking tape)
• Circular saw ? (for trimming)
• Wood plane (for trimming or beveling)
• Hammer ?
• Punch

Installation Steps

Step 1: Remove Packaging and Inspect Slab

• Remove shipping materials such as corner covers, shipping blocks, or pads.
• Inspect the slab for cosmetic damage, squareness, and warp.
• Verify it is the correct product (size, color, design, handing, etc.). If any concerns arise, do not install the slab and contact the supplier.

Step 2: Inspect Existing Jamb

Verify the existing jamb is square, level, and plumb.

• The jamb should be 3/16" wider than the slab and at least 3/8" taller.
• Ensure sufficient clearance between the jamb edge and the stop to accommodate the slab thickness.
• Verify Squareness: Measure diagonally across the jamb opening (A and B). Measurements should be the same. Maximum allowable deviation is 1/8".
• Verify Plumbness: Check vertical jambs for plumbness (C, E, D). Maximum allowable deviation is 1/8".
• Verify Flatness: The opening floor or sill must be flat and level (D). The face of the rough opening must be in a single plane (E) with less than 1/8" twist from corner to corner.

DO NOT install the slab unless the jamb meets these conditions. Professional assistance may be needed to correct any problems before installation.

For Retrofit Installations: Remove the old door and contact local waste management entities for proper disposal or recycling.

Step 3: Install Slab

Prepare Jambs and Slab

1. Measure the existing frame (not the stop) from floor to head and side to side to verify the slab will fit. The frame should be 3/16" wider than the slab (allowing 1/16" clearance on the hinge jamb and 1/8" on the strike jamb) and tall enough (usually 3/8"-1/2" taller) to allow 1/8" clearance on the head jamb and prevent rubbing on flooring.
2. Trimming: A maximum of 1/4" can be trimmed from each edge of hollow or solid core molded and flush slabs. For best appearance, trim equally from opposite sides. Apply masking tape along the cut line on each face of the slab to minimize chipping. Use a fine-toothed circular saw and wood plane for cuts. Re-bevel if necessary after trimming beveled edges.
   Diagram Description: Shows a door slab with indicated trim-able portions on the top rail, stile, and bottom rail, marked with 1/4" allowances.
3. Bevel: The latch stile/edge may have a pre-cut 2° or 3° bevel for 1/8" clearance against the strike jamb. If not beveled, use a wood plane or fine-toothed saw to create a bevel so the face against the stop is slightly narrower than the opposite face.
   Diagram Description: Shows a door slab edge with a bevel and indicates clearance between the slab and jamb.

Test Slab Fit in Jambs

Before installing hardware, fit the slab into the frame. Ensure there is at least 1/16" clearance on the hinge side and 1/8" clearance on the strike and head jamb sides when the slab is closed.

Diagram Description: Illustrates the clearances required between the slab and the jambs (hinge jamb, strike jamb, head jamb).

Lock Block Identification

NOTICE: Markings indicate the top edge and which side of the slab should be positioned towards the strike jamb.

If installing a hollow core door without a lock set hole, refer to the top edge stamp (e.g., "<LB, LB>" or "<LB>") which indicates the lock block location. Use the lock set manufacturer's instructions and template to drill for the lock set.

Diagram Description: Shows an example of a top rail door identification stamp and lock block locations marked on a door slab.

Install Hinges

NOTICE: Three hinges are recommended for slabs up to 84" in height and four hinges for slabs over 84".

1. Existing Frame: If re-using the existing frame, verify hinge locations are plumb or in a straight vertical line. Position new hinges in existing locations and modify hinge routes as needed. Match slab to jambs.
2. New Frame: Measure down from the underside of the head jamb 7" for the top hinge. Measure up from the bottom of the slab 10" for the bottom hinge. Place the middle hinge halfway between.
3. Marking Slab for Hinges: Ensure the distance from the top of the slab to the top of the hinge route is 1/8" less than the distance from the head jamb to the top of the top hinge. This creates a 1/8" gap at the head jamb.
4. Marking Slab Depth: The distance from the inside face to the back of the hinge route should be 1/16" less than the depth of the hinge route on the hinge jamb.
5. Marking and Notching: Use a template to mark hinge jambs and slab. Notch the jamb and slab for hinge leaves to the depth of the leaves.
6. Drilling and Installation: Mark screw hole locations and drill pilot holes. Separate hinge leaves by removing the hinge pin (use hammer and punch). Install leaves separately on jambs and slab. Use a hand screwdriver for screws into the slab to prevent stripping. Hang the slab by aligning hinge leaves and re-install hinge pins.

Diagram Description: Illustrates hinge placement and required clearances between the slab and jambs.

Step 4: Complete Installation

Install Lock Set and Finish Installation

1. Lock Set Placement: The center of the lock set hole is typically 36" from the bottom edge of the slab. The on-center measurement from the latch edge is usually 2 3/8" or 2 3/4", depending on the lock set. If a rail is present, center the lock set on the rail. A 2 1/8" diameter hole is generally needed for the lock set. Drill a 1" latch hole through the slab edge into the center of the lock hole for the latch. Some latches require chiseling the slab edge for a flush fit. Drill pilot holes for attachment screws. Round (contractor drive-in) latches can be tapped in with a hammer.
2. Check Operation: Close the slab and check for proper operation. Adjust as necessary.
3. Finish Surfaces: Finish all slab surfaces if not already done.
4. Secure Hinges (Solid Core/Premium Composite/Stile and Rail): For these types of slabs, install a #9 x 2 1/2" screw in the center hole of the top two hinges, passing through the leaves into the jamb. This provides extra security.

Diagram Description: Shows the placement of the lock set hole and latch hole on the door slab. Depicts using a longer screw in the top hinge for added security.

Lowe's Installation Services: Ask about Lowe's installation services. Learn more at lowes.com/installation.