Notes and Clarifications of Table Above

Highly Insulating: Concrete block with lathe furring and vermiculite has an R-value of about 5. Both wood frame and foam forms have R-values in the 9 to 19 range. Tech Block has a clear wall R-value of 47.5.

Foam Forms: (ICFs: Insulated Concrete Forms) are generally some variation of polystyrene panels held together by steel or plastic ties. The panels are designed to fit together in such a way that a space is left between them for concrete. Drywall is usually attached by screwing into plastic strips embedded into the interior face of the wall, or by "furring out" a secondary interior wall. Stucco is adhered to the exterior by attaching wire mesh. See also Why Use Tech Block®.

Stucco/Masonry Ready: The exterior surface of Tech Block is designed to immediately accept stucco without the need for wire mesh. (Independent tests have shown that stucco bonds directly to the surface of Tech Block with at least 3 times the strength of the bond achieved with the wood frame/wire mesh approach.) CMU block is comparable to Tech Block in this regard, but wood frame walls need at the very least the application of wire mesh that has building paper attached to it. More often polystyrene, plywood, AIS board, or OSB panels are first nailed to the studs to act as backing for the stucco and wire mesh. Foam forms require wire mesh, and some jurisdictions mandate that special kinds of stucco be used on foam, which adds to cost. The simple addition of brick ties placed between the Tech Blocks during stacking is all that is needed to prepare the wall for masonry- based stone or brick veneer.

Drywall Ready: Tech Block walls are ready for drywall installation immediately upon erection. Wood frame walls, on the other hand, will need to be insulated, and may need diagonal corner bracing. CMU block walls need to be "furred out", which is the process of attaching wood strips to the blocks as an attachment surface for drywall. ICFs claim to be ready for drywall, but this is somewhat misleading in that there are many areas in the typical home where the ICF foam walls need to be enhanced before other items can be attached to them. The installation into foam of backing for items like kitchen cabinets, interior walls, shelving, drape hardware, towel racks, bath tubs, shower stalls, baseboard, casing, and/or fire blocking is problematic with ICFs. This is one of the biggest flaws with these types of wall systems.

Waterproof: Tech Blocks used under grade (below ground) do not have the OSB layer. Wood frame construction is susceptible to dry rot which results from moisture permeating the wall. There are currently hundreds of thousands of wood frame homes in the southeastern United States that are falling to pieces due to water vapor being trapped behind synthetic stucco, as was reported on the 20/20 TV news program in July 1999. A Tech Block wall is stuccoed right down to the footing which, when added to our waterproof block material, forms a solid barrier against water infiltration.

Termite Resistant: The Tech Block Wall System is designed to be stuccoed right down to the footing. This creates a formidable barrier to termite infestation. Both CMU and ICF walls match the Tech Block resistance to termites, but wood frame walls are notoriously susceptible to termites.

Fire Resistant: We applied the flame of a cutting torch to our block material for two hours. The block material did not burn and there was no discernible rise in temperature on the other side of the block. The polystyrene insulation in Tech Block is encased in cement which inhibits melting. Further, the strength of our walls is dependent on the concrete and steel that is inside the block channels, so our walls may be blackened by fire but will remain standing and structurally sound. The OSB layer on the interior surface of Tech Block is sandwiched in between block material and drywall in a finished wall. The drywall has a half hour fire rating and the sandwich design eliminates open spaces that support the traveling of fire through a wall. Of course, wood frame walls will burn. The foam panels in ICFs will melt, but they won't feed a fire and have good fire resistance because of this and their concrete cores.

Sound Resistant: Sound is resisted in two ways: It is reflected by hard surfaces, and it is absorbed by porous surfaces. Tech Blocks, CMU blocks, and ICFs all have a combination of both surfaces and are all very sound resistant. Wood frame walls, however, transmit sound fairly well and must be specially enhanced if sound resistance is a concern.

Easy To Erect: When comparing the ease of construction of various wall systems, each system must be completed to the same stage in order to make a fair comparison. For instance, framing wood stud walls is quick and easy, but it isn't the whole picture. One would have to consider the installation of bracing, backing, fire blocking, batt insulation, foam panels, house wrap, and wire mesh to bring a wood frame wall to the same stage that Tech Block achieves when it is initially installed. When all of the components necessary to construct a completed wall are considered, it becomes evident that both wood stud walls and Tech Block walls can be described as moderately easy to erect.

CMU block, on the other hand, is labor intensive. Cinder block walls are held together with mortar joints, the installation of which is time consuming and requires specialized equipment and expertise.

Uses Concrete Efficiently: Tech Block forms a wall that contains within it an interconnecting steel-reinforced concrete gridwork. This cage-like design gives our walls strength without having to use massive amounts of concrete, which is expensive and heavy.