Types of Drywall Used in Illinois Homes

Not all drywall is the same panel, and putting the wrong one in the wrong room is one of the most expensive mistakes we see on Illinois homes. This guide walks through every drywall type you'll actually encounter in an Illinois home, what each is for, and where the IRC (as adopted across Illinois) requires a specific spec.

Standard 1/2" drywall - the Illinois workhorse

Standard 1/2" gypsum board (Sheetrock, Gold Bond, CertainTeed, and other brands) is the default on interior walls in most Illinois homes framed at 16" on center. It's paper-faced, roughly 1.6 lbs per sq ft, and takes joint compound, texture, and paint the same way regardless of manufacturer. For most bedrooms, hallways, living rooms, and closets in Illinois, this is what goes up. Sheetrock is just USG's brand name for the same product - see our sheetrock repair and installation page for the brand-name breakdown.

5/8" Type-X fire-rated drywall - required in Illinois garages and ceilings

5/8" Type-X is fire-rated gypsum board with glass fibers in the core that resist burn-through. Under the IRC as adopted in Illinois, it's required on: garage walls that share space with living areas, garage ceilings under living space, some multi-family shared walls, and ceilings framed at 24" on center to prevent sag over time. Skipping it in an Illinois attached-garage remodel is a common inspection failure. Full installation cost context lives on our drywall installation cost per square foot in Illinois pillar.

Moisture-resistant drywall ("green board") for Illinois bathrooms and laundries

Green board (or its paperless successor, often called AquaTough or DensArmor) is standard drywall with a water-resistant paper facing and mold-inhibiting additives in the gypsum core. In Illinois it belongs in bathrooms outside the tub/shower area, laundry rooms, mudrooms, and utility rooms. It is not a tile substrate - it will fail behind tile in a wet area. Behind tile in a shower or tub surround, use cement board or a purpose-made tile backer instead.

Mold-resistant paperless drywall ("purple board") for Illinois basements

Paperless mold-resistant board (Gold Bond XP, DensArmor Plus, and similar) replaces the paper facing with fiberglass mat, which mold can't feed on. It costs roughly 15% more than standard, and it's the right call on Illinois basement walls that see 65% relative humidity in July and occasionally get spring seepage. Full basement wall assembly detail is on our Illinois basement drywall best practices guide.

Cement board for Illinois wet areas

Cement board (Durock, HardieBacker, Wonderboard) is a Portland-cement-based panel that doesn't degrade when wet. It's the correct substrate behind tile in showers, tub surrounds, and steam rooms in Illinois homes - not moisture-resistant drywall. It's heavier than gypsum board and requires carbide tools to cut, but it's non-negotiable in true wet areas.

Soundproofing drywall (QuietRock and mass-loaded panels)

Sound-attenuating drywall (QuietRock, SilentFX, and similar) is a laminated panel with a viscoelastic damping layer in the core. In Illinois it shows up in home theaters, shared walls between bedrooms and mechanical rooms, and townhome demising walls. It's roughly 3-4x the cost of standard board, so we spec it only where the sound-transmission-class (STC) upgrade actually matters.

Abuse-resistant and impact-resistant drywall for Illinois commercial and high-traffic residential

AR (abuse-resistant) and IR (impact-resistant) panels have reinforced cores that resist doorknob dents, mop-handle strikes, and stroller impacts. In Illinois they're common in mudroom hallways, garage entries, and commercial buildouts across Schaumburg office and retail spaces. See our commercial drywall page for how we spec them on tenant improvements.

Ceiling drywall - what to specify in Illinois

5/8" board on ceilings framed at 24" on center. Standard 1/2" board only works on ceilings framed at 16" o.c. because it sags between wider joist spacing. For textured ceilings that get repaired often, we spec ceiling-grade board (lightweight, sag-resistant) rather than standard 1/2" - a small upgrade that matters over 20 years of Illinois humidity cycling.

Which drywall type belongs where in an Illinois home

• Bedrooms, hallways, living areas - 1/2" standard on 16" o.c. framing
• Ceilings on 16" o.c. framing - 1/2" standard (or 1/2" ceiling-grade)
• Ceilings on 24" o.c. framing - 5/8" (Type-X where fire code applies)
• Garage walls sharing living space - 5/8" Type-X, Illinois code
• Garage ceilings under living space - 5/8" Type-X
• Bathrooms and laundries (dry side) - moisture-resistant green board or paperless
• Shower and tub surround substrate - cement board, not drywall
• Illinois basement walls - paperless mold-resistant board
• Home theater and shared bedroom walls - QuietRock or double-layer 5/8"
• High-traffic hallways and commercial - abuse or impact-resistant board

For drywall installation anywhere in Illinois, we spec every room on the estimate before ordering material - so the right panel goes in the right place the first time. For drywall repair on existing panels, we match the panel type in the existing wall so the patch performs identically to its neighbors.