A:  I don't recommend anything more than at 4 foot intervals for main tee supports.

A:  Steve Thank you for your inquiry. Hanger wires supporting main tees should not exceed 4' o.c. Main tees can be spaced 4' o.c. For sloped ceilings us our SB2 Sloped Ceiling Bracket to attach the wall mold at an angle. Hope this helps.

A:  Hello Danny, Thank you for your recent inquiry about the 15/16 in. x 12 ft. Ceiling Grid Fire code Main Tee, carton of 20. Please see the Installation Guide on the webpage, this will provide information for estimating the amount of material needed for your project. Thank you for shopping Home Depot.

A:  Thank you for your inquiry. Hanger wire (12 gauge) is required when suspending Donn Main tees. Hope this helps.

A:  Andy Thank you for your question. The Pro Desk can assist you in estimating what materials you need, or you can use our online Ceilings Material Estimator by going to www.usg.com and selecting "Installation and Technical" in the upper right hand corner. Your suspended ceiling will require wall mold, 12' main tees, 4' cross tees and 12 gauge hanger wire. If you plan to use 2' x 2' ceiling tiles you will also need 2' cross tees.

A:  Hello! The answer is it depends! The quantities will vary dramatically based on the shape of the room, the choice of 2 x 2 tile vs 2 x 4 tile, the amount and style of lighting employed etc. The link to USG below will be of help. https://www.usg.com/content/usgcom/en/resource-center/tools/ceilingmaterialestimator.html For some basics, the aluminum angles are merely based on the full perimeter of the room, less wast for bends, short piece fall off/trimming, some damage that will inevitably occur, etc. So, were it 60' x 60', you would need 75 main tees, 450 2'cross tees, 450 4' cross tees, and 900 2' x 2' panels Were it 120' x 30', most everything is the same with exception made for the perimeter angle. There is more perimeter for the same area, so angle count increases to 25. Things get more complex when you need to compensate for off square and non-straight walls. For this large an area, add at least one "bay" to both the length and width to allow for "centering" the field, allowing a half bay all around the nice and square and center the "center block" of tile that will be an exact 2' or 4' increment. None of this allows for actual waste, or mistakes, nor does it include the hanging materials, typically 12 ga annealed steel hanger wire and the attachment point to your existing ceiling or roof, or truss .... Remember to deduct a tile for every matched size troffer fixture if they are your lighting selection. Always add extra tile for "crib stock", to use when the almost inevitable drip or stain, or basketball etc that will damage a tile or two (or 20?) during it's life. Some styles of panel do go out of favor and then become obsoleted, there are also lot to lot variations in color, texture, and perforation pattern to consider. If hanging troffer lighting check local codes to ascertain that the fixtures may need to be suspended independently of the grid, some fixtures have tabs that can be bent over the grid, but then the grid typically needs to be supported at or very near each corner. Cutting irregular shapes or corners adds material usage as well, specialty peices are available for neater outside corners of angle, Pop rivets may be needed, and are surely desirable for connecting the grid ends to the perimeter angles. (absilutely required for a seismic area, as are many additional details. For a project of this scale, its no small task, yet is not technically difficult! Squareness and straightness and staying flat are critical in this size project, laser sights and laser levels will be of great help! Joe Good luck!