U Value Calculation Of Brick Wall

Introduction & Importance

U value, or thermal transmittance, is a crucial factor in determining the energy efficiency of a building. For brick walls, understanding the u value is essential for designing effective insulation strategies and ensuring compliance with building regulations.

How to Use This Calculator

1. Enter the thickness and density of the brick.
2. Enter the thickness and conductivity of the mortar.
3. Click ‘Calculate’.

Formula & Methodology

The u value of a brick wall is calculated using the following formula:

U = (1 / (1 / λ_b * t_b + 1 / λ_m * t_m)) + R_s

Where:

• U is the thermal transmittance (W/m²K)
• λ_b is the thermal conductivity of the brick (W/mK)
• t_b is the thickness of the brick (m)
• λ_m is the thermal conductivity of the mortar (W/mK)
• t_m is the thickness of the mortar (m)
• R_s is the surface resistance (m²K)/W

Real-World Examples

Data & Statistics

Thermal Conductivity of Common Bricks (W/mK)

Brick Type	Thermal Conductivity
Clay	0.8 – 1.2
Aerated Concrete	0.1 – 0.2
Concrete	1.5 – 2.5

Thermal Conductivity of Common Mortars (W/mK)

Mortar Type	Thermal Conductivity
Cement:Sand (1:3)	0.8 – 1.2
Lime:Sand (1:3)	0.7 – 1.1
Eco Mortar	0.3 – 0.5

Expert Tips

• Use high-density bricks for better thermal mass.
• Minimize mortar thickness to reduce thermal bridging.
• Consider using insulating mortars for improved performance.

1. Check local building regulations for u value requirements.
2. Consult with a professional if you’re unsure about any aspect of the calculation.

Interactive FAQ

What is the difference between u value and R value?

U value and R value are both measures of thermal resistance, but they are used in different contexts. U value is used to describe the heat transfer through a material or assembly, while R value is used to describe the thermal resistance of a material.

U.S. Department of Energy – Thermal Performance of Insulation

BuildingGreen – Understanding U-Values and R-Values