All About ‘r’ Values

EcoBlox excels in energy efficiency, providing superior thermal performance for modern homes. These blocks have excellent R-values and U-factors, ensuring effective insulation and stable indoor temperatures year-round. The high thermal mass of EcoBlox stores and releases heat efficiently, reducing energy demands and utility costs. By using EcoBlox, homeowners can enjoy a more comfortable living environment while significantly lowering their energy consumption and environmental impact.

Thermal Mass Benefits

Helps in reducing energy demands by storing and releasing heat.

R-Value and U-Factor

EcoBlox offers superior thermal insulation, maintaining stable indoor temperatures.

What is the R-value of an EcoBlox?

The R-value of an EcoBlox is roughly 0.42 per inch.  But there’s more to it when trying to understand the thermal performance of a wall assembly in the building envelope. 

R-value is a measurement of a material’s resistance to heat flow and the greater the R-value the less heat flows across the material.  U-factor is the reciprocal of R-value and is a measure of the heat transfer in a material.  A lower U-factor means less heat flows across a material.  Units for R-value in the U.S. are hour-ft3-deg F per Btu.  This means that the heat loss per hour across a wall is a function of the R-value, the area of the wall, and the temperature differential across the wall. 

EcoBlox, and the majority of masonry walls, have the ability to store significant amounts of heat when in contact with direct solar gain.  Due to the greater weight when compared to traditional wood frame construction, masonry walls tend to release this heat slowly which in turn reduces the peak energy demand for heating.  A similar effect can be observed in climates where energy is primarily used for cooling.  The effect of this heat storage is the thermal equivalent of a mechanical flywheel – it evens out building energy requirements.

An inconsistency arises when predicting energy usage using only R-value.  R-value does not account for the stored or released energy inherent to mass wall construction.  Previous attempts have been made to provide a modification factor for the R-value to incorporate this effect.  The M-factor was introduced as a result of research conducted in the 1970’s that indicated heavy masonry walls had an effectively higher R-value in most climate zones.  The M-factor served well for nearly 20 years until new energy codes were developed in the U.S. 

Today, nearly all new structures must comply with energy code requirements.  The current method of recognizing the effect of thermal mass is reflected in the energy code requirements by specifying minimum R-values for mass walls separately from those listed for wood-framed walls. 

Reference: 
Thermal Advantages of Masonry Walls, David Woodham, P.E. Atkinson-Noland & Associates, Inc