Threshold heights

[bigdog]

Hi Jerry

I see a lot of newer impact rated exterior doors with very high thresholds (2-3") that are in my opinion trip hazards. I know the thresholds are high for wind driven water resistance but I have 2 questions on this.

1) The everyday steel insulated doors from big box stores (hey that rhymes) have a threshold about an inch high and are also impact rated and acceptable for the same locations your expensive impact doors with high thresholds are used. How do the two relate?

and

2) I found a reference to 3/4 of an inch being the maximum high for a protrusion from the floor in B1010.1.7. The 2 exceptions that allow higher (up to 7 3/4" really?) don't seem to apply to front doors that should be considered a means of egress. Also how would that apply to a 10 story condo building with 1 front door and just windows? Do I have my building types screwed up?

David

[Jerry Peck - Codeman]

[bigdog]

Jerry,

I was mainly referring to residential but have gone to the egress (front) door of condos and found excessively high thresholds on newer impact rated doors.

After looking through the FBC residential the only relevant section I could find was R311.3.1 which states a maximum of 1.5 inches on the interior side as the exterior is allowed up to 7 3/4". I also couldn't find anything other than stairs specs to define interior changes of elevation.

Is the front door always considered an "egress" door? And if so would any hinged front door threshold protruding more than 1.5 inches above the finish floor be a violation? as well as a trip hazard.

David

[Jerry Peck - Codeman]