4” Exterior Insulation for High-Performance & Wildfire-Resistant Homes (WUI Build)

Описание: This project dives deep into why exterior insulation is essential for high-performance homes, especially when building in WUI (Wildland-Urban Interface) fire-prone areas. This isn’t theory—this is a real assembly designed to manage thermal performance, air control, moisture, wind loading, and wildfire exposure.

In this build, we install 4 inches of continuous exterior insulation using a two-layer system:

2” polyiso at R-7.2 per inch, followed by

2” mineral wool (Powerwool) at R-4.6 per inch,
for a total of ~24R of exterior insulation alone.

This layered approach wasn’t the original plan. After months of delays and no communication from Rockwool—despite full payment—we pivoted. Polyiso allowed us to keep the project moving, and we ultimately found Powerwool, which enabled us to complete a fire-resilient exterior wall assembly that performs both thermally and defensively.

🔹 The video covers critical real-world details builders often miss:
🔹 Continuous insulation from foundation to wall transitions
🔹 Structural nailers and Z-girts that actually work
🔹 Corners, cantilevers, penetrations, vents, and inspections
🔹 Concealed downspouts and future-proof detailing
🔹 Fire-rated foams, intumescent coatings, and live fire experiments

We also run hands-on fire tests with intumescent paint and mineral wool to visually demonstrate how different materials behave under heat exposure—because material choice matters when embers, radiant heat, and flame fronts are real risks.

Fire protection isn’t one product—it’s an assembly mindset. Exterior insulation can either become a vulnerability or a defensive layer, depending on how it’s designed and installed.

If you’re building or retrofitting in a wildfire zone and care about durability, resilience, and performance, this video shows what that actually looks like in the field.

⏱️ Chapters:
0:00 Exterior Insulation Installation for High-Performance Homes
0:34 Why Continuous Exterior Insulation Matters
2:32 Foundation to Wall Continuous Insulation Transition
4:20 Structural Nailers for Siding Over Exterior Insulation
5:36 Z-Girts Explained for Exterior Insulation Assemblies
7:30 Siding Thickness Defines Exterior Insulation Extensions
10:10 Rockwool Supply Failure & Why We Changed Materials
13:06 Critical Corner Details for Exterior Insulation
14:18 Concealed Downspouts & Gutter Integration
14:48 Fire Testing Intumescent Paint & Mineral Wool
19:05 Cantilever Exterior Insulation Detailing
20:58 Exterior Insulation & Future Building Inspections
21:54 Corner Drainage & Downspout Fire Details
23:02 Staggered Insulation & Fire-Rated Foam Sealing
24:40 Fire-Resistant Venting with Vulcan Vents
27:57 Penetrations Through Exterior Insulation
29:12 Range Hood Venting & Core Drilling
29:51 Why Concealed Downspouts Matter
31:27 Wind-Resistant Exterior Insulation Assembly (100 MPH)

#ExteriorInsulation
#HighPerformanceHomes
#WildfireResistant
#WUIConstruction
#buildingscience
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