Iron Door Measuring Guide

How rough Opening Size relates to Door Size

The rough opening should be 1” wider and 1” taller if it has wood floors and 1” wider and ½” taller if it has tile flooring from the outside dimensions of the door jamb in order to easily fit the jamb into place.

If you are replacing an existing door

Interior trim around the door needs to be removed to be able to see the house framing. Then you will need to find the studs that define the rough opening. Also, remove the threshold so that you can see the subfloor. If the threshold cannot be removed, you will need to establish the position of the subfloor with a probe.

Rough Opening – Width

Measure the width between the studs at three places – at the top of the opening, at the middle, and the bottom. The smallest of these measurements should be recorded as the rough opening’width.

Rough Opening-Height

Measure from the sub floor to the header beam above the door. For a straight topped door, measure on both sides and record the smallest measurement as the rough opening height. If there is going to be a replacement of an arched door, also get the measurement from center.
Then, the center measurement will be the rough opening height and the difference between the center and the outside corners height is the amount of "fall" on the arch.
If you have any confusion or question about this, please contact us.

For New Construction

The same rules apply for a new door as a replacement door. The rough opening must be 1” wider and 1” taller if it has wood floors and 1“ wider and ½” taller if it has tile flooring than the outside dimensions of the door jamb.
However, in many new constructions it may be possible to modify the building to fit the door unit to some extent. This always depends on other factors affecting the building designs from the outside and inside on how far along the construction has proceeded.

If you are in the design stage the whole design of your entryway can be worth considering and foyer in relation to the possibilities of door, sidelights and transom options. Real Estate experts often note that the house entrance is one of the most important aspects that affect the appeal and the value of a home.

Threshold Height and Flooring

The threshold is the sill at the bottom of the door that forms a barrier between the inside and outside. It also is what the dropseal on the bottom of the door seals against when the door is closed. All our entry doors have an integral Threshold.
The nominal distance from the bottom of the threshold to the bottom of the door is 2”, however the actual threshold height is less than this to make room for the dropseal. The rough opening height will be effectively reduced by the amount you raise the threshold. Please see the following diagram: