Choosing the right type of drywall for your San Diego home or commercial space is more than a matter of preference—it’s a crucial decision that affects comfort, safety, and long-term performance. With San Diego’s unique coastal climate, varying building codes, and diverse property types, knowing when to use moisture-resistant, soundproof, or fire-rated drywall can save you money and prevent future issues.
In this comprehensive guide, we’ll help you understand each type of drywall and show you where, why, and how to use it—drawing on expertise from SGP Drywall, San Diego’s trusted drywall professionals.
Why Drywall Selection Matters in San Diego
Local Conditions that Affect Drywall
Coastal Humidity: Salt air and ocean proximity increase moisture exposure
Temperature Fluctuations: Though mild, they can cause expansion/contraction
Earthquakes: Lightweight, reinforced drywall is preferred in seismic zones
Code Regulations: Fire-rated materials required for garages, multifamily walls
Choosing the wrong type of drywall can lead to:
Mold growth and water damage
Poor sound insulation in rental units or offices
Failure to pass building inspections
Safety risks in the event of a fire
That’s why working with experienced contractors like SGP Drywall is key.
1. Moisture-Resistant Drywall (Greenboard/Purple Board)
What It Is
Moisture-resistant drywall is treated with additives to resist humidity and mold. It’s typically green or purple in color.
Best For:
Bathrooms
Kitchens
Laundry rooms
Basement walls
Why It’s Essential in San Diego:
High humidity and salty air near the coast
Bathroom walls near beach homes often fail without moisture resistance
Key Benefits:
Mold resistance
Higher water tolerance
Durable in humid environments
Explore our Drywall Installation page for options in kitchens and baths.
2. Soundproof Drywall
What It Is
Drywall specifically engineered for noise reduction. These panels often include viscoelastic polymers or dense gypsum layers for sound dampening.
Best For:
ADUs and rental properties
Home theaters
Nurseries
Offices and conference rooms
Local Use Cases in San Diego:
ADUs in North Park or City Heights
Multi-tenant properties in Chula Vista
Commercial buildings in Downtown San Diego
Key Benefits:
Higher STC (Sound Transmission Class) ratings
Better acoustic separation
Reduces neighbor-to-neighbor noise complaints
Want better acoustic privacy? Visit our Wall Texturing & Finishing service page to finish your soundproof installation.
3. Fire-Rated Drywall (Type X and Type C)
What It Is
This drywall is made with special non-combustible additives and is designed to slow fire spread.
Required For:
Garages (per code)
Shared walls between multi-family units
Walls adjacent to furnaces or HVAC closets
Commercial kitchens
San Diego Building Code Notes:
The city requires fire-rated drywall in:
ADUs within 5 feet of the primary residence
Townhomes and condos
Detached garages
Key Benefits:
Slows fire progression
Provides time for evacuation
Mandatory for permit compliance
Read about Water Damage Repair to understand how compromised fire-rated drywall can affect safety.

Comparing Drywall Types
Type | Moisture-Resistant | Soundproof | Fire-Rated |
Best For | Bathrooms, Kitchens | Bedrooms, ADUs | Garages, Utilities |
Cost (per sheet) | $15–$20 | $30–$50 | $18–$25 |
Thickness | 1/2″ – 5/8″ | 5/8″ | 5/8″ (Type X/C) |
Benefits | Mold-proof, humidity control | Privacy, acoustic control | Code compliance, fire protection |
When to Use Combinations
Most San Diego homes need more than one type of drywall:
A bathroom wall in an ADU might need both moisture and fire resistance
A garage ADU may require fire-rated and soundproof boards
Home offices in multifamily units may need acoustic insulation
Work with a team like SGP Drywall to build a plan that covers all compliance and comfort needs.
How SGP Drywall Helps You Choose
We don’t just install—we help you plan:
Code evaluation for permits
Material selection based on room type
Expert installation of every board type
Finishing to blend all drywall surfaces
Explore our Sheetrock Finishing service to ensure your specialized drywall looks flawless and uniform.
Mistakes to Avoid When Choosing Drywall
Using standard drywall in wet areas
Forgetting fire-rated board in garage-to-house walls
Overlooking soundproofing in shared tenant walls
Skipping permits and getting flagged by inspectors
Real San Diego Case Studies
“We used soundproof drywall in our garage-turned-office, and it made a huge difference—can’t hear street noise anymore!” – Jessica A., University Heights
“SGP recommended moisture-resistant drywall for our kitchen ADU. We passed the inspection the first time!” – Nicholas Y., Del Mar
Conclusion
Drywall isn’t one-size-fits-all—especially in San Diego’s diverse environments. Whether you need fire safety, acoustic control, or moisture protection, choosing the right type of drywall is essential for performance, comfort, and compliance.
Need help selecting and installing the right drywall? Contact SGP Drywall today. We specialize in:
Call (619) 806-2169 or request a free consultation online.