Field note
Type G laminating screws for gypsum to gypsum
Type G is the laminating screw. Coarse-pitch, high thread, made to bite gypsum core, not a stud. A longer Type S is made to reach steel through two layers. Those are different jobs. Mixing them on a rated multi-layer wall is how a listing fails in the field.
This page restates public class language from ASTM C1002, Gypsum Association fastener notes, and mill laminating notes. Official fastener data — Grabber and peers — should match the class. Current sheets: grabberpro.com. Not a SKU catalog. Cluster: Fasteners. Hang sequence: how to hang drywall.
What Type G is
C1002 Type G is a coarse-pitch, high-thread, self-piercing screw for fastening gypsum panel products to gypsum board. The high thread is the point: it needs purchase in a gypsum core that would strip a fine-thread Type S and would not see a wood stud at all.
What it fastens. A face layer laminated to a base layer — adhesive plus mechanical, or the mechanical part of a laminated system the mill or the listed design named. Curved work, overlays, column wraps, and some double-layer separations when the face is not driven through to framing.
What it is not. Not Type S into steel. Not Type W into wood. Not a metal-to-metal framing screw. Not a silent “double hang” if you skip the adhesive the design named, or skip the fasteners the adhesive schedule named. See Type S vs Type W vs laminating.
Bugle head is still typical so the face can be finished. Depth still matters. Punching the face paper on a laminated layer is the same photograph as punching a single layer — the taper cannot hide torn paper.
Adhesive is a different product on the same takeoff
Laminating adhesive is the gypsum mill’s laminating adhesive, applied to that mill’s pattern — strips, spots, or the layout the sheet names. Type G without adhesive is not automatically the laminated system the listing tested. Adhesive without the fastener schedule the design named is not a silent double hang either.
Two common field mixes, and they are not interchangeable:
- Face layer fastened through to framing. Base-layer spacing often opens up because the face layer’s Type S or Type W is doing the structural hang into studs. The face layer follows single-layer rules into the member. You want the thread that matches the stud, at the length that reaches it through both layers — Type S or Type W, not Type G.
- Face layer laminated, not driven to the stud. Type G (and the mill’s adhesive) follow the laminating schedule, not the single-layer wall table. This is the Type G job.
Rated multi-layer walls are the wrong place to improvise. Pull the UL / GA-600 design. Some listed walls want all layers screwed to framing. Some allow a laminated face. The PDF wins.
Length and pattern
Type G length has to engage the base-layer core without punching through the assembly into a cavity you did not mean to enter, and without leaving the head proud. Manufacturer application notes and the listed design name the length. Do not grab a 1-5/8-inch Type S coil and call it laminating because “it is long.”
Spacing on a laminated face is not the 16-inch wall table from C840’s single-layer hang. It is the mill’s laminating fastener spacing — often tighter, often in a grid that works with the adhesive pattern. Confirm the current mill sheet and the fire design. Edge distance still respects paper edges.
Dimple, do not punch. Same finish rule as every other gypsum face. See how to hang drywall.
Commercial vs residential
Commercial wall and ceiling. Type G shows up on laminated faces the design actually named, on column and beam wraps, on curved bulkheads, and on some shaft or chase faces when the listing uses a laminated layer. It is a specialty coil, not the corridor hang coil. The everyday commercial hang is Type S (or S-12). Do not laminate a 1-hour corridor because the Type G box was open.
Residential production. Type G is occasional: overlays, a curved wall, some double-layer garage or townhome separations when the documents actually laminate. It is not in the everyday 1/2-inch Type W coil. Hanging two layers both screwed to wood is not a Type G job — that is two Type W (or Type S) lengths.
Adhesive tubes for laminating are not construction adhesive from a punch cart. Use the mill’s laminating product the board manufacturer will stand behind.
What to put on the takeoff
Separate lines:
- Laminating adhesive (mill, pattern)
- Type G class and length, if the face is not driven to framing
- Face-layer Type S or Type W at the through-to-stud length, if the face is driven to framing
- Base-layer fastener class and the opened-up spacing if that is what the design uses
Do not write “double hang — extra screws.” Official data: Grabber, grabberpro.com. Directory: Fasteners, Tools. Products: Products. Steel members behind a laminated commercial wall: steel stud framing basics. No ASINs, no affiliate URLs. Affiliate disclosure.
FAQ
Is a laminating screw the same as a longer Type S?
No. Type G holds gypsum to gypsum. A longer Type S reaches steel through two layers. The listed design says which one you are looking at.
Can I skip adhesive if I use Type G?
Only if the design and the mill sheet say mechanical-only. Many laminated systems are adhesive plus fasteners. Do not skip a component the listing tested.
Can Type G hang board to a stud?
That is the wrong thread for wood or steel. Use Type W or Type S (or S-12) into the member.
Does Type G change finish level?
No. Head still dimples. Torn paper still photographs. GA-214 is the finish document.
Where do we buy them?
Fastener house and gypsum house, not a random “drywall screw” bin. Official sheets: grabberpro.com.