From: WinDor, Inc
Re: Doors with low profile sills
Please find the following warranty and testing information as it pertains to your above referenced order.
The intent of this letter is to advise you of the issues inherent to the use of low profile sills on exterior doors and bifold windows. WinDor doors with low profile sills include swing doors with ADA compliant sills, Bi-fold Doors and bifold windows with U channel or ADA compliant sills.
Due to the design of ADA compliant and low profile sills, door products with these sills do not carry a design pressure (DP) rating for air or water infiltration. Furthermore, because of the low profile sill design, these doors will not provide the same air, water or structural performance as doors with a standard sill height and design configuration and, therefore, are susceptible to air and water leakage and potential insect intrusion.
WinDor doors manufactured with ADA compliant and low profile sills carry a warranty only on the workmanship, hybrid panels and frame, painting if applicable and insulated glass as defined by the WinDor Limited Warranty dated 8/19/14. No warranty applies to product performance ratings.
There are a variety of design options you can incorporate into your building to help you deal with the potential air and water leakage issues inherent to the design of doors with low profile sills, please consult your local representative for suggestions.
In areas adjacent to the doors, do not specify flooring materials that may be susceptible to damage when exposed to weather such as hardwood or carpet.
As your large opening door supplier, we want to remain a valued member of your team. We hope that the information included above will clarify the issues that may potentially be caused by the design of ADA compliant and low profile sills. We also hope that this information will help you proactively address the potential leakage issues through the use of creative design solutions.