DASMA TDS 180 - Wind Load Ratings for Non-Tested Garage Door Sizes

Manufacturers test a limited set of door sizes to earn a wind load rating. They then sell dozens of other sizes based on that testing. DASMA TDS 180 defines the rules for how ratings carry over to sizes that were never put in a test chamber.

What this data sheet says

DASMA TDS 180 establishes a framework for assigning wind load pressure ratings (in pounds per square foot) to non-tested door sizes by interpolating from structurally tested sizes. A tested size is one that physically passed the ANSI/DASMA 108 uniform static air pressure test at a given design pressure.

"A door that has not been tested may be assigned a wind load rating by interpolation from tested sizes, provided the interpolated size is within the bounds established by the tested matrix."

The sheet makes a key restriction clear: interpolation is only valid when the non-tested size falls within the tested matrix boundaries. A size that exceeds the largest tested width or height in the matrix cannot carry an interpolated rating; it requires independent testing.

The TDS also addresses rolling doors alongside sectional garage doors, because both product types face the same question when non-standard opening sizes are ordered.

When it applies

TDS 180 comes up in two practical situations:

Custom door sizes. A homeowner who orders a 9-foot-wide door in a market where manufacturers primarily test 8x7 and 10x7 sizes needs to know whether the 9x7 door carries a valid wind pressure rating. TDS 180 governs whether the manufacturer can assign one by interpolation or must test it.

Permit and plan review. Denver and other Front Range jurisdictions require structural documentation for wind-load-rated doors. A building official reviewing a 15x8 opening will look at the manufacturer's pressure certificate and verify it was either directly tested or properly interpolated under TDS 180.

In Denver, the design wind speed is 115 mph (Vult, Exposure C). That translates to roughly 24 to 30 psf depending on the opening size and ASCE 7-22 calculation method. Doors in non-standard sizes must document how their rating was established.

What this means for you

Ask your dealer for the pressure certificate, not just the "wind-rated" label. A certificate shows the rated psf and whether that rating came from direct test or interpolation. Both are legitimate, but the interpolated rating only applies when the door size is within the tested matrix.

Non-standard widths or heights need extra verification. If you are specifying a 14-foot-wide or 9-foot-tall door, confirm with the manufacturer that the size falls within the interpolated range. If it does not, the door needs its own structural test or a site-specific engineering letter.

G Brothers can pull manufacturer pressure certificates for any door we install and confirm compliance with Denver and Front Range permit requirements before the job starts.

Full text and source

Download DASMA TDS 180 from the official TDS index at https://www.dasma.com/technical-data-sheets/.

This entry covers sectional garage doors and rolling doors for commercial and residential applications. Fire-rated rolling doors have separate testing and rating requirements outside the scope of TDS 180.