M-D Building Products Adjustable Aluminum & Hardwood Threshold

Product Overview

The M-D Adjustable Aluminum & Hardwood Threshold is designed to effectively seal uneven gaps beneath your door, providing protection against drafts, moisture, dust, and insects. This durable threshold is suitable for both new door installations and as a replacement for existing thresholds. It features an adjustable oak riser that can be set from 1-1/8 inches to 1-3/8 inches to ensure a weather-tight seal. Constructed from heavy-duty aluminum and sturdy oak wood, it is built for years of reliable performance.

• Material: Durable aluminum and sturdy oak wood
• Application: Ideal for replacing exterior door thresholds
• Dimensions: 5-5/8 in. W x 1-1/8 in. H x 36 in. L
• Color: Silver aluminum with unfinished oak
• Protection: Seals against drafts, moisture, dust and insects
• Adjustability: Adjustable riser to seal unique and uneven gaps (1-1/8" to 1-3/8")
• Installation: Fasteners, bolts, nuts, cap, and screws are all included
• Door Swing: Can be positioned for outswing or inswing doors
• Finish: Unfinished oak is ready for staining, priming, or painting

Figure 1: M-D Building Products Adjustable Aluminum & Hardwood Threshold.

Setup & Installation

Before beginning installation, ensure you have all necessary tools and hardware. The threshold can be cut to a desired length using a hacksaw if needed. For optimal sealing, this product can be used in conjunction with a door sweep or an under door seal.

Required Tools & Materials:

• Adjustable Threshold (correct size)
• Hacksaw or Sawzall with bi-metal blade
• Hammer drill (for concrete applications)
• Flathead screwdriver (long and regular size)
• Phillips screwdriver
• Tape measure
• Sharpie or pencil for marking
• Safety glasses and gloves
• Scraper tool or putty knife (for old adhesive removal)
• Knee pad (optional, for comfort)
• Shop towels
• All-purpose latex silicone caulk
• Broom or shop vac for cleanup
• Concrete anchors (if installing on concrete)
• Blue painter's tape (for marking drill depth)

Installation Steps:

1. Remove Old Threshold:

   Carefully remove any existing screws from the top of the old threshold. If the threshold is glued or nailed from the sides, use a multi-tool or Sawzall to cut it in half for easier removal. Use a flathead screwdriver or pry bar to lift and remove the old threshold pieces. Be aware of any hidden nails or screws underneath. Scrape away any old glue, caulk, or debris from the subfloor to ensure a clean surface for the new installation. Sweep or vacuum the area thoroughly.

   

   Figure 2: Close-up view of the adjustable riser and aluminum base.

2. Measure and Cut New Threshold:

   Measure the exact width of your doorway opening. The M-D 78600 threshold is 36 inches long and may need to be cut to fit your specific opening. Use a tape measure and a Sharpie to mark the precise cutting line on the threshold. For a clean, straight cut, use a speed square to guide your hacksaw or Sawzall with a bi-metal blade. Ensure the cut is perfectly straight for a proper fit.

   

   Figure 3: Threshold dimensions and adjustable range.

3. Prepare for Installation:

   Before placing the new threshold, ensure the subfloor is completely clean and dry. Apply a generous bead of all-purpose latex silicone caulk along the subfloor where the threshold will sit. This creates a watertight seal and helps secure the threshold in place.

4. Install New Threshold:

   Carefully position the new threshold into the doorway opening, pressing it firmly into the caulk. Ensure it is centered and flush with the door frame. Use a hammer to gently tap the threshold into place if needed. For concrete subfloors, use a hammer drill to pre-drill holes for the included concrete anchors. Mark the drill bit with blue tape to ensure you drill to the correct depth for the anchors. Insert the plastic anchors into the pre-drilled holes. Then, drive the screws through the pre-drilled holes in the threshold and into the anchors, securing the threshold firmly to the subfloor. Do not overtighten.

   

   Figure 4: Threshold installed in a doorway.

Operating Instructions

The M-D Adjustable Aluminum & Hardwood Threshold features an adjustable oak riser. To adjust the height of the riser, use a flathead screwdriver to turn the screws located on the top surface of the oak piece. Turning the screws clockwise will raise the riser, while turning them counter-clockwise will lower it. Adjust the riser until it creates a snug, weather-tight seal with the bottom of your door, eliminating any uneven gaps.

Maintenance

Regularly inspect your threshold for any signs of wear, damage, or loose screws. Clean the aluminum and oak surfaces with a mild soap and water solution. For the unfinished oak, consider applying a stain, primer, or paint to protect it from moisture and prolong its lifespan. Periodically check the seal between the threshold and the door to ensure it remains effective against drafts and moisture. Reapply caulk if any gaps appear.

Troubleshooting

• Drafts or Moisture Leaks:

  Check the adjustment of the oak riser. It may need to be raised to create a tighter seal. Also, inspect the caulk lines around the threshold for any cracks or gaps and reapply caulk as needed. Consider adding a door sweep or under door seal for enhanced protection.

• Difficulty Adjusting Riser:

  Ensure the adjustment screws are not stripped or damaged. Clean any debris from the adjustment mechanism. If the wood is swollen, allow it to dry before attempting further adjustments. Lubricating the screws with a silicone spray may help.

• Threshold Feels Loose:

  Check the installation screws. If they are loose, tighten them carefully. If the anchors in concrete are failing, you may need to use larger anchors or a different type of concrete fastener.

Specifications

Warranty & Support

This M-D Building Products threshold comes with a manufacturer's warranty. For specific details regarding warranty coverage, claims, or product support, please refer to the documentation included with your purchase or visit the official M-D Building Products website.

Official Product Video

Watch this official product video from M-D Building Products for an overview of the adjustable threshold:

Video 1: M-D Building Products 78600 Adjustable Threshold Overview.