“Screen Grid vs Solid Wall: Which ICF Insulates Better? The Real Thermal Performance Behind ICF México Systems”

ICF México
Dec 10
2 min read

ICF (Insulating Concrete Forms) is known worldwide for delivering energy efficiency, comfort, and exceptional structural performance. In Mexico, two ICF wall configurations dominate the market:

Screen Grid ICF (post & beam) — ICF-15 and ICF-20
Solid Wall ICF (monolithic core) — StrongWall

Both deliver outstanding thermal insulation, but each behaves differently due to concrete distribution and thermal mass.

Let’s break down how each system insulates and which one is best for every type of project.

1. How Thermal Insulation Works in ICF

In ICF construction, the majority of the insulation comes from EPS foam—not from the concrete.Concrete contributes structural performance and thermal mass, while EPS:

Reduces heat transfer
Eliminates thermal bridging
Maintains stable indoor temperatures
Reduces HVAC energy consumption by up to 50%

This means both systems offer elite insulation, though their thermal behavior varies by mass and continuity.

2. Screen Grid ICF (ICF-15 & ICF-20): Maximum Insulation with Lower Thermal Mass

Screen Grid ICF uses:

Reinforced concrete cores (vertical + horizontal)
Large sections of uninterrupted EPS
Complete thermal bridge elimination

R-Values (Mexico):

ICF-15 → R-17+
ICF-20 → R-26+

Thermal Advantages

High percentage of EPS → extremely low heat transfer
No continuous concrete path
Better performance in hot climates
Lower conduction compared to solid systems

Perfect for warm regions and residential projects.

3. Solid Wall ICF: Maximum Thermal Mass + Continuous Insulation

Solid Wall ICF features:

A 100% continuous monolithic concrete core
EPS layers on both sides ensuring uninterrupted insulation

R-Values (by core thickness):

4” → R-22
5.5” → R-24
7.5” → R-26

Thermal Advantages

Extremely high thermal mass
Superior thermal lag (delay in heat flow)
Exceptional interior stability
Best for buildings with internal heat loads

Ideal for hotels, offices, warehouses, and mixed-climate regions.

4. Side-by-Side Comparison

Feature	Screen Grid (ICF-15 / ICF-20)	Solid Wall (StrongWall)
R-Value	R-17+ to R-26+	R-22 to R-26
Thermal Mass	Medium	Very high
Thermal Bridges	Zero	Zero
Thermal Lag	Excellent	Superior
Hot Climate Comfort	🔥 Best	Very high
Mixed or Cold Nights	High	🔥 Best
Cost per m²	Lower	Higher
Typical Use	Homes & mid-rise buildings	Hotels, hospitals, industrial