Product Codes

Design Pressure Requirements

Design Pressure (DP) testing measures the performance of fenestration products to withstand positive and negative pressures. The positive DP number is the standard for wind blowing at the building (windward) and the negative DP number represents the vacuum pressure on the opposite side of the building (leeward).

Design pressure requirements will vary based upon wind zone designation in your geographic location (see Florida map as an example), density of nearby buildings, fenestration height from the ground, fenestration location on the side of the building, etc. Florida has had specific wind zone performance requirements for many years, as found in the Florida Building Code. Other states continue to adopt design pressure requirements.