A Guide to Securely Fastening Your Fireboard
This article is a guide to securely fastening your Fireboard. Fireboard is a term used mostly in the United Kingdom to describe fire-resistant drywall. Also referred to as Type-X in the United States, fireboard provides up to an additional hour and a half of fire and smoke protection versus regular drywall. Fireboard has a much denser core and contains glass fibers along with the gypsum that keep the wall from crumbling during the intense heat from a fire. It also dampens sound transmission, so most building codes require it's use on ceilings in apartment buildings, as well as walls separating attached garages. Fireboard can be fastened in a number of ways, just like traditional drywall, we will go over the advantages and disadvantages of each one. You can use one, or a combination of all three fastening methods.
Nails are the first option. Nails can only be used if you are mounting the drywall to wood. Nails for drywall have ringed or barbed shanks and are typically blue in color. The nails also have a large head to help keep it from piercing through the paper of the drywall. Nail sizes for each thickness of fireboard should be: 1/2 inch thick fireboard = 1 1/4 inch nails, 5/8 inch thick fireboard = 1 3/8 inch nails. Another thing to pay attention to, nails do have a tendency to pop back through the finished surface. You can help prevent this by placing a second nail 2 inches from the first. Nails should be spaced between 6 inches to 8 inches apart. You can expect to use a pound of nails for every 200 square feet of fireboard.
Screws are the second option. Screws have superior holding power, are easier to use, and will not pop back through a finished surface. If you are attaching the fireboard to metal, you must use screws. An electric drywall screw gun will help with setting the screws at the perfect depth. You can use 1 1/4 inch screws for any thickness of drywall, and although they are more expensive than nails, you use less of them. You should place screws 12 to 16 inches apart, and it will take only 1/2 a pound of screws to finish 200 square feet.
Lastly, there is panel adhesive. Panel adhesive provides excellent bonding if you are attaching the fireboard to any old drywall, paneling, or plaster. Panel adhesive is not recommended for use on ceilings alone, you need to additionally secure it using nails or screws. You will need 2 tubes of panel adhesive for 200 square feet. Also, a good guideline to go by, you should use panel adhesive in temperatures between 40 degrees F to 100 degrees F.
Since fireboard is usually used for ceilings, here are some tips to help with a ceiling installation. Always install fireboard across the joists on the ceiling. If at all possible have two people to help install the fireboard on the ceiling, one to hold it up and the other to nail. If you don't have another person to help you, you can make a T-brace from a 2 inch piece of 1-by-4 inch nailed to the end of a 2-by-4 inch of sufficient length to reach from the floor to the ceiling. If you are using nails and adhesive, apply the adhesive first, then lift the sheet of fireboard up and place 3 nails across the fireboard at each joist. If you are just using nails, space them about 7 inches apart.
Installing and fastening fireboard is really not that different from using traditional drywall, so even a novice builder can manage it easily. Since the cost of fireboard is only slightly more than traditional drywall it should increase in popularity for both it's fire-resistant and sound dampening qualities.