Are internal doors a standard size?

Are internal doors a standard size?

Welcome to the world of home design, where even the smallest details matter. If you've ever wondered, "Are internal doors a standard size?" you're not alone. In this guide, we'll explore the differences between all the sizes available with internal doors.

Understanding the Basics:

Width Matters:

Internal doors in Ireland come in a range of widths, typically from 711 mm (28 inches) to 864 mm (34 inches). The standard width often hovers around 762 mm (30 inches). Smaller doors are available for doors like hot presses or under stairs toilers. You can usually get doors in as small as 610 mm (24 inches) off the shelf!

Height Highlights:

When it comes to height, internal doors typically stand between 1981 mm (78 inches) and 2032 mm (80 inches). Keep in mind that doors usually step up to 2032 mm when the width goes wider than 762 mm (30 inches).

The Right Thickness:

Don't overlook thickness! Internal doors usually have a thickness ranging from 35 mm (1.375 inches) to 44 mm (1.75 inches), ensuring durability and stability for everyday use. As standard the most common doors we see and supply are 44 mm thick. Thinner doors are normally found in older homes.

Embracing Variations:

While these measurements offer a general guide, it's crucial to understand that not all doors conform to the same standards. Consider these variations:

Specialized Doors:

  • Sliding Doors: Ideal for saving space, sliding doors may have unique dimensions.
  • Pocket Doors: Tucked away when not in use, pocket doors may have dimensions tailored to specific needs.

Challenges in Fitting New Doors:

When replacing internal doors, one common challenge is fitting them into existing door frames. Here are some considerations:

Uneven Door Frames:

It's not uncommon for door frames to be slightly uneven or not perfectly square, especially in older homes. This can pose challenges when installing a new door.

Modifications may be Needed:

To ensure a proper fit, you might need to make small modifications to the door. This can involve trimming or adjusting the door to accommodate any irregularities in the frame.

Considering Door Frame Replacement:

If the existing door frame presents significant challenges, another option is to replace the door frame along with the doors. This ensures a seamless fit and eliminates potential issues arising from an old or misaligned frame.

Tips for Home Renovators:

If you're in the midst of renovations and tackling door replacements, here are some extra tips:
  1. Accurate Measurements: Precisely measure your existing door frames to anticipate potential fitting challenges.
  2. Consult with Experts: Check in with your local door supplier who will be able to offer advice. Here at doors and floors we deal with the public on a daily basis and are always happy to help a DIYer!
  3. Frame Replacement: If your door frames pose difficulties, consider replacing them along with the doors for a hassle-free solution.


In the world of internal doors, one size does not fit all. Embrace the variety available in Ireland, and let your home's personality shine through your choice of doors. Whether you opt for standard sizes, explore doors with unique dimensions, or consider frame replacements, remember that the perfect door is the one that suits your unique space.