There are few products that can adapt to a vast array of architectural styles, remain cost-effective and meet the ever demanding energy and structural code criteria like Omni Block.
Omni Block is a uniquely designed block with that is multi-layered with constricted (reduced) and offset cross webbing that create individual cells. These cells are filled with corresponding foam insulation inserts (two models). It is a stand alone wall system that should not be furred, additionally insulated or sheet-rocked. It is recommended to plaster the interior of the block with standard sheetrock compound to exactly match any adjoining interior sheetrock (see DRYWALL section).
Omni Block can also be left exposed on the interior, exterior or both. This type of construction economically provides finish options that other types of construction techniques cannot as easily provide.
The complete Omni Block System 8 is depicted above. It consists of six types of block, the Stretcher unit is the most commonly used. The other units, the Left Corner/Jamb and Right Corner/Jamb, which are alternatively used at corners, in-line piers, and window and door jambs. Also required at window and door jambs are standard 8″ x 8″ x 8″ half block. There are a few situations that call for a closed-ended block on both ends and that is where a standard 8″ x 8″ x 16″ is used. Finally, above openings and top-of-wall where horizontal rebar and grout are specified, a bond beam block is used.
High Tech in an earthy sort of way
1. The design includes a middle lineal wall or commonly called a middle face shell. This is an important feature of the block design because heat seeks to cool; principle of physics. Block is a very slow conductor of heat. The exterior heat source is the sun, which has solar energy rays that hit the exterior of the block and starts to drive heat through the block. Unlike standard block, the Omni Block design is a maze for the solar energy, which is sufficiently delayed in part by the middle lineal wall. The sun eventually rises to the point it is no longer on the wall so the heat within the block begins to gradually subside. This is in effect is a “thermal flywheel”. On the interior, the block face that is heated by an interior source (ie,. furnace, fireplace, wood-burning stove) will absorb a thin layer of heat, but does not have the energy to penetrate the block, so sits on the surface of the block. When the room cools, the heat leaves the wall surface to heat the cooler ambient air.
2. The natural beauty of the block and in some cases the block aggregate can be exposed. The architectural expression is vast utilizing the combination of integral pigment color and black, grey, red, brown, yellow or other aggregates. The block can be split to achieve a rougher texture where no two block are ever alike. The block surface can be burnished (ground) to almost as smooth of texture as your kitchen granite countertop. The block can be sandblasted providing a very soft surface or shot-blasted yielding a courser texture.
3. The long cavity created by the block design houses the long Expanded Polystyrene (EPS) insert. The insert is designed with vertical flutes to fit snugly into the cavity, but still allow any moisture that possibly could enter through a mortar joint to migrate within the wall along with air and eventually dry. Included in the long insert design is a strategic horizontal notch along the bottom that does not interfere with potential mortar weepage to the interior side of the block. EPS is a safe, non-toxic, non-outgassing, non-flammable by-product of petroleum. It is made from the “sludge” found at the very bottom of a barrel of oil; after all the other products (gasoline, diesel, kerosene, motor oil and the like) are harvested. Before EPS was invented, this sludge was put into landfills where it would never decompose. Therefore it is generally considered a highly “green” product.
4 and 8. In addition to the natural beauty available, the exterior surface is the first line of defense structurally and thermally. It takes a very long time of the sun’s solar energy to penetrate all the way through the exterior wall membrane of the block.
5 and 10. The offset and constricted cross webs effectively reduce the thermal bridging of typical concrete block designs. Heat is forced into smaller ducts or pathways which slows its transference. The economical advantage is that this constriction also reduces the amount of raw material that is required to produce an Omni Block unit and lightens it for the mason.
6. The interior block surface should never be covered with layers of additional insulation or sheets of drywall. These materials cover the thermal mass properties of the block and prohibits it from moderating interior building temperatures. A thin coat of drywall material does not diminish the thermal mass properties and will look the same as adjacent drywall.
7. The short insert has the same attributes as the long insert with the additional vertical notch to permit vertical mortar joint mortar weepage to occur. Masons simply cannot have the inserts inhibited by mortar blockages. If this routinely happened, it would slow the installation process down and increase costs.
Per structural engineering, the short insert is periodically left out of the cavity and rebar and grout is then installed. Omni Block is a reinforced masonry system and engineered as such. There is no “perfect” building system, but when insulation is removed from the wall, it is replaced with more thermal mass to the interior side of the building.
9. The exposed interior surface will passively absorb heat out of the room and in cooler climates release it back into the room as it cools. This is the affect of thermal mass. Caves remain cool in the summer and warm in the winter. Block materials’ natural temperature is 56°F. Block materials are aggregates of the earth. Below the freeze/thaw line that varies in climatic conditions, the earth is 56°F all over the world. To illustrate, put your hand on a granite countertop. You feel considerable cool, but what is really happening is the heat from your body is being absorbed/transferred to the cooler granite. Heat always seeks cool. It is a principle of physics.
11. The inserts are 8″ tall and are designed to slide down into the block after it is laid. The tops of the inserts are placed even with the top of the block which does not inhibit or interfere with the mason laying a subsequent course. However, the insert extends below the block and covers the 3/8″ horizontal mortar joints. The 3/8″ vertical mortar joints are also protected by the short insert overlapping from one half cavity of one block and the other half cavity from the adjacent block. If you consider that mortar joints are 7% of the total wall, this feature is tantamount to total thermal protection.
The inserts come in two sizes; Long and Short. Each fits into its corresponding block cavity. The inserts are 3/8″ taller than the block in order to insulate the horizontal mortar joints. The vertical mortar joints are insulated due to the overlapping feature (from block-to-block) of the short insert. The “whole wall” is insulated, not just individual block.
The inserts are Expanded Polystyrene (EPS) and not only provide excellent insulation, but have other favorable properties such as; they are non-toxic, do not “out-gas”, have minimal flame spread characteristics, and are manufactured with a closed looped steam process that has virtually no carbon footprint on the earth.
For detailed information visit Insulation Inserts.