Door Molding Quantity Calculator

Please check.

Since door frame molding is installed only on the left, right, and top three sides (U-shape], excluding the floor threshold, the floor length is excluded from the calculation.
Since the recently popular 9mm door frame requires no height difference between the door frame and the wall, wall leveling work such as puttying and sanding must be done beforehand.
After removing the existing door frame, if the urethane foam between the door frame and the wall is protruding, trim it flat with a knife and then attach the new molding.
If you are only refurbishing the door without replacing it, you must check the direction in which the door opens (pull/push] and ensure that the molding does not catch on the hinges.

How about this calculator?

Door Frame Molding Quantity Calculator, Material Calculation Guide for Door Refurbishment and Door Frame Replacement

The most effective way to refurbish an old door is to replace the door frame molding. Door frame molding is a finishing material that covers the gap between the door frame and the wallpaper, and it is usually installed in a U-shape. If you input the inner dimensions of the door frame and the width of the molding, this calculator accurately calculates the actual quantity of molding required by taking into account the length increase from the top miter joint (45 degrees] and the loss rate.

Door Frame Molding Quantity Calculation Formula

It is calculated based on construction on 3 sides (left/right/top] with the floor open.

Total required length

Total Length (mm] = {(Height + Molding Width] x 2} + {Width + (Molding Width x 2]} + Allowance

Final required quantity

Required Quantity (units] = Total Length Required ÷ Length of One Unit of Material

Since additional length equal to the molding width is required for the top corner assembly, you must consider a miter markup.

Detailed Guide to Calculator Input Items

Please verify the door frame measurement data and material specifications for accurate material calculation.

1. Door frame width, height

Enter the inner width of the door frame and the height from the floor to the top (inner dimensions]. When installing a ram, please enter the ceiling height.

2. Door frame molding width

This is the width of the door frame molding to be used. For flat molding, 60mm to 80mm sizes are most commonly used.

3. Markup rate and length

It is recommended to leave a 5~10% margin to account for 45-degree cutting loss, and the length of one piece of material is based on the standard specification of 2,400mm.

Guide to Major Door Frame Installation Types and Features

Types of construction	Main materials	characteristic	note
General plain text selection	MDF wrapping molding	The most popular and clean finish	Door renovation standards
Foam door frame	PVC material molding	It is resistant to moisture and does not swell in water.	Bathroom construction recommended
9mm line	MDF board cutting	Trendy design with minimized thickness	Woodworking and film work are essential.

Expert Know-how and Checklists

This is the key point that determines the quality of the door frame work.

45-degree miter joint vs. 90-degree right-angle construction
If precise miter joints are difficult to achieve when joining the top corners, the right-angle construction method (flat line] where a long top molding is placed and supported by left and right columns is much more advantageous for DIY construction.
Height setting during lintel (ramma] installation
If you want a ramma installation that extends up to the ceiling, please enter the actual ceiling height in the height value. The empty space at the top must be filled by cutting MDF panels separately.
Check door stopper installation
Due to the thickness of the door frame molding, interference may occur on the hinge side when opening the door 180 degrees, so it is recommended to install a floor stopper to prevent the handle from touching the wall.

Frequently Asked Questions (FAQ]

Q. How much does molding cost to refurbish one door?
A. Usually, if you order 3 pieces per door based on standard size (2.4m] molding, you can install it comfortably on the left, right, and top sides.

Q. Is it possible to get a 9mm door trim using ready-made molding?
A. It is impossible with just ready-made molding; sawing MDF panels and applying a film finish are essential. If you simply want to achieve the desired look, I recommend cutting thin flat molding to size.

Q. What material should I use for the bathroom door frame?
A. Due to the high humidity in bathrooms, using standard MDF molding poses a high risk of swelling and cracking when wet. You must use water-resistant ABS foam door molding to ensure longevity.