How to Install a Prehung Door for Beginners? Prehung Interior door Installation Instruction

Even though prehung doors are usually easier to install than slab doors, you still need basic repair skills, including precision and accuracy. After all, a properly mounted door unit beautifies the doorway, functions properly, and lasts a long time without needing to be replaced.

If you have purchased a prehung door and plan to install it yourself, we have prepared step-by-step instructions to help you avoid mistakes and do everything like a professional.

What is a prehung door?

Before we pull out the right tools, let's learn the theory. What is the difference between a prehung door and a slab door?

A slab door is a simplified "version" of a door that does not have a frame or hardware. That is, both of these parts are purchased separately.

A prehung door is a ready-to-use product consisting of a door slab with a frame and hinges. You only need to choose a handle in the showroom or on the website.

Unpacking and preparing tools

The DIY-friendly Belldinni set includes:

• Door slab (pre-cut for hinges and American standard lock).

• Door frame (jambs).

• 3D adjustable concealed hinges.

• EZ-Hang is a unique seven-bracket door installation system that can be used at any stage of construction.

Necessary tools:

• Screwdriver.

• Screws 1 5/8”.

• Pencil.

• Tape measure.

• Level.

• Shims.

• Safety glasses.

• Garbage bags.

Step 1: Check your order

First, check the contents of your door unit.

Next, make sure your rough opening is level and sized according to the following formula for proper installation:

The rough opening should always be 2'' wider and 2'' higher than the door slab.

The table shows the ratios of slab height to door opening.

The table shows the ratios of slab width to door opening.

To determine the correct size slab, take six measurements of the doorway using a tape measure:

• Measure the width at the rough opening's bottom, middle, and top and record the greatest value, adding 2 inches.

• Measure the height at the left, middle, and top of the rough opening and record the largest value, adding 2 inches.

Also check the swing direction: left or right-hand inswing door.

Step 2: Connect the door frame

The frame supplied is disassembled. The following elements must connect its parts:

• Connectors (4 pcs).

• Screws (4 pcs).

• Dowels (2 pcs).

Step 3: Attach EZ-hangers

With EZ-Hang patented technology, hanging an interior door is five times faster. Its advantage is that the attachment is adjustable: there's no requirement to bend or alter the bracket, and it is suitable for either or both sides of the door, with or without drywall.

Attach one hanger on the jamb just above the top hinge and the other slightly below the bottom. Place the third hanger approximately in the middle. Repeat the same on the second jamb, observing the existing distances.

Each quick hanger requires three screws, you need a total of 18 ones.

Step 4: Lay out the markings

At this stage, use a level and a pencil. Approximately ¾'' from the rough opening, make a marking so that you know where to attach the hangers installed on the frame in the future.

Step 5: Install the door frame

Carefully lift the door frame and level it in the rough opening. If you took the measurements correctly before purchasing the interior door, the jambs should fit into it

Step 6: Align and screw in the door frame

Once the frame is level in the rough opening, use a drill and six screws to fasten it to the hangers. Follow the markings made in Step 4.

Step 7: Screw the hinges to the door slab

Fix the two hinges to the slab pre-cut for the hardware with six screws. The Belldinni door unit kit includes concealed hinges.

Step 8: Screw on the door hinges

Install the slab in the doorway by screwing its hinges to the frame. You will again need six screws for this.

If the slab is heavy enough, work with a helper, although homeowners can usually mount the interior door alone.

Step 9: Install the door slab

After you have secured the slab to the frame, check that the door works properly. It should open and close smoothly and unobstructed.

Step 10: Adjustment and installation

First, check and adjust the hinge side of the jamb according to the level.

Fix the hinge side jamb to the wall with the help of EZ hangers, 1 ⅝" screws and shims if necessary. Unscrew the screws of the strike plate side (handle side) of the jamb. Align the slab within the frame, minding the gaps between the slab and the jambs.

The hinge side of the jamb is already fixed to the wall, so the strike plate side and the header need to be adjusted. Please note that metal hangers can be bent. In some installation cases, you would need to bend them during the door installation to achieve the best installation result.

Attach the strike plate side and the header to the wall in the same way, using hangers, screws, and shims.

Step 11: Moldings installation

Install the casings for each side of the slab so that they fit snugly around the perimeter of the door unit. Lightly tap the right, left, and top casings to secure them.

Step 12: It's done

The installation is complete! Check once again that the door is working correctly.

If you have followed our instructions clearly, you can rest assured that the pre-finished interior door will last for many years without needing to be replaced.

Beginners sometimes need help to install an interior door independently, and there is an explanation for this. Formalizing a doorway requires time, careful study of guides, having the necessary tools at home, appropriate skills, confidence in their abilities, etc. To make repairs the first time without errors and quickly, we recommend applying for a professional service to install prehung and other doors. Our experts install door units of high quality and on time. Contact them at doors-install.com.