In the interview, Jeff Speck talks about when to use lightweight concrete blocks and when to use normal concrete blocks. Essentially, lightweight blocks can be used at any time, with the exception of very high compressive strength requirements. Lightweight CMUs that meet the requirements of ASTM C90 have all the structural properties of normal weight load-bearing units. The next interview topic includes the comparison of performance between the two, including acoustic properties. Speck talks about the two different measures of acoustic properties, Sound Transmission Class (STC) and NRC (Noise Reduction Coefficient) in relation to wall thickness and how well a wall absorbs the sound.
Additionally, the interview covers the issue of sustainability. Because Lightweight concrete (LWC) solutions offer improved energy performance, reduced volume of materials, reduced transportation requirements, improved service life, and lower life-cycle costs, the product is more sustainable and green than normal concrete solutions. The next interview topic deals with costs. Lightweight blocks are thinner and lighter, meaning a reduced volume of materials and more efficient costs. The final interview question pertains to how internal curing improves the performance of concrete and how it relates to sustainability.
To read the full Q & A article, view the photos below. Enlarge the photos by clicking on them. Also, the online version is available at http://bit.ly/p93xl5.