Understanding Ultimate And Nominal Design Pressures For Windows And Doors

Windows and sliding glass doors must meet the requirements of industry standards that include air water and structural testing.

Understanding ultimate and nominal design pressures for windows and doors.

As required by the florida building code every new window installed must meet a minimum design load pressure. Let s start with the definition of design pressure. According to aama american architectural manufacturers association wdma window and door manufacturers association and the nafs north american fenestration standard design pressure dp is a rating that identifies the load. As defined by the aama american architectural manufacturers association wdma window and door manufacturers association and the nfrc national fenestration rating council design pressure is a rating that identifies the load induced by wind and or static snow that a product is rated to withstand in its end use application.

10 psf asd general requirements. The water penetration resistance test pressure for r products is also 15 of dp. Design pressure testing measures the performance of fenestration products to withstand positive and negative pressures. What this means is that a lab has carefully tested a window s design pressure by measuring how many pounds of pressure per.

Exterior windows and doors shall be designed to resist the design wind loads specified in table r301 2 2 adjusted for height and exposure per table r301 2 3. It just starts at 2 9 psf for the gateway dp of 15. Using this design pressure as a basic element architectural designs for building walls doors and windows are created accordingly. The pressure is caused by wind blowing on and around the subject property.

High speed wind such as wind during a hurricane creates positive and negative pressures and this pressure can tear out windows and doors break glass and force rain into your home. A dp or design pressure rating is a numerical value given to a building component that represents its ability to withstand a given amount of wind load. National building codes now require testing and certification of windows. Design pressures are the amount of pressure put on the openings envelopes windows doors during a hurricane.

A higher dp value indicates a window or door that can withstand more wind water and or structural load than a window with a lower dp. Dp ratings represent three performance elements structural load water resistance and air infiltration resistance. Combined together all these factors give a measure of design pressure which is the product of all these different pressures a building is exposed to. Dp stands for design pressure.

Minimum design wind pressures the design wind pressure for c c shall not be less than a net pressure including internal pressures of 16 psf acting in either direction normal to the surface i e. What is design pressure and how does it impact the windows or doors you are considering for your home. Understanding design pressures are relatively simple.