US20060150559A1

US20060150559A1 - Two piece interlocking block system

Info

Publication number: US20060150559A1
Application number: US11/305,396
Authority: US
Inventors: Juan Haener
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-12-17
Filing date: 2005-12-16
Publication date: 2006-07-13
Also published as: WO2006066249A3; WO2006066249A2

Abstract

An interlocking block system consisting of a full block and a half block are installed mortar free with the internal cells filled with grout as required. The blocks must be laid in the upright position but may be rotated end to end as required for aesthetic reasons or to create an additional square internal cell. The blocks are supported by a tongue and groove engagement at the four external corners and four internal locking members that engage within the block on the course above. Knockout sections and relief areas are supplied for the installation of reinforcing bars. When the blocks are turned at a ninety degree angle to make a corner, the internal locking members engage in the square end cell of the block above equally as well as they do in a straight course of blocks.

Description

The present invention claims priority to U.S. Provisional Patent Application No. 60/637,298, filed Dec. 17, 2004. It relates to building blocks, which are conventionally employed to construct a variety of structures. More particularly the device herein disclosed relates to a building block system that employs only two configurations of blocks to build an extremely strong and stable structure. Two configurations will be available in a variety of common block sizes. The system employing a full block and a half block uses a novel means of interlocking external tongues and grooves along with internal locking members to provide an incredibly strong sheer resistant structure. The two-piece interlocking block system works as effectively on corners as it does on straight sections. With the addition of optional reinforcing bars and grout filled cells, the resulting wall provides resistance to earthquakes and other lateral forces which might cause failure in walls lacking the structural integrity provided by the interlocking system of the disclosed device herein referred to as the Haener two piece interlocking block system.

FIELD OF THE INVENTION

Background of the Invention

The present invention generally relates to construction materials and, more particularly, to a mortar free block of an improved type. Conventional concrete block walls are laid up by a time-consuming difficult system that involves concrete mortar being placed onto the footing or the top of a course of previously laid blocks and then setting blocks one at a time in the mortar. In each instance the mason applies mortar to the end wall of block to join them together end to end.
This procedure is continued until the required courses are in place. Great care must be taken to keep each course perfectly horizontal and straight and the spacing between blocks even with additional time required in the finishing of the mortar joints on both sides of the wall surfaces. It takes a skilled block mason with years of experience to lay block properly with even spacing end to end and between courses. The use of a great deal of skilled laborers on a jobsite keeps the cost of this type of construction high.
Various types of interlocking blocks have been devised in the past to facilitate block laying; however, most such blocks are very expensive to produce since the interlocking portions, usually grooves and protrusions, normally are sawed into or otherwise fashioned in the blocks after they are initially formed by the molding process. Some of the interlocking blocks require a wide variety of different shapes of blocks to accomplish the tasks and are usually very fragile and subject to breakage. Moreover, those blocks in which the interlocking components are initially molded usually are difficult to mold with the acceptably close tolerances that are required.
Accordingly, it would be desirable to be able to provide an improved mortar free building block featuring improved adaptability, strength and economy. The design of the block should be such that it can be readily molded and released from the forming mold with the full detail preserved, obviating any subsequent reshaping and finishing. Moreover, the block should be easily strengthened with reinforcing bars if needed, and should be capable of being fabricated in a full array of sizes, but still having only two basic configurations.

REFERENCES SITED

U.S. Pat. No. 6,134,853 of Juan Haener describes an insulated building block system for use in building walls and other structures. Each full block has sidewalls and end walls with a generally open interior and flat upper and lower surfaces. Two vertical ridges are provided along the interior of one sidewall, with a protrusion extending above the upper surface. The ridges are located such that an upper block arranged in staggered relationship to a block in a lower course will interlock with the lower block. Recesses are provided in the interior end wall surfaces to retain a thermal insulation panel against the interior sidewall surface opposite the ridges. Half blocks are also provided to fill spaces in wall end surfaces between staggered full blocks. The half blocks have open interiors for placement of insulation panels and include ridges for interlocking with protrusions on adjacent full blocks. First rebar ends extending up through lower courses filled with cement grout may be fastened to second rebar ends extending down through upper courses and aligned with the first rebar by ways of a loop of material secured to the second rebar. The second rebar end with the loop is inserted through an opening in the upper courses until the loop surrounds the extended end of the first rebar. Then the second rebar is rotated to wind the loop material around the second rebar, bringing the ends of the first and second rebar together.
This patent, while a leader in its field, describes a mortar free block that was designed for its insulation capabilities having a single central chamber in which foam insulation material can be inserted. This block has the external tongue and groove end engagement but only has two interlocking protrusions on one side of the block creating a block that cannot be reversed and can only be used in one plane. With one central chamber and no center wall, the block, while useful for the intended purpose, is rendered fragile and subject to inadvertent breakage.
U.S. Pat. No. 5,575,128 of Juan Haener teaches of an interlocking lock system for mortar free wall or other structure assembly in which a plurality of blocks are laid up in courses in a staggered relationship. Only two different block configurations are required, the first, or long, blocks having a length at least twice the block height and the second, or short, blocks having a length up to half the length of the first blocks. Each of the blocks has a pair of upright sidewalls having a flat top and bottom surface and generally parallel outermost side surfaces and at least two spaced transverse walls. Protrusions on the inner surfaces of the sidewalls extend from a base generally coplanar with the block bottom surface to a top extending above the block top surface and configured so that the tops and bases interlock when the blocks are laid up in staggered courses. Further interlock arrangements are provided so that the long blocks will interlock when positioned either parallel along walls or perpendicular at corners. A tongue and groove interlock configuration is provided at the ends of the blocks so that the ends interlock.
This patent teaches of another mortar free block with a single central chamber with external tongue and groove engagement with three interlocking protrusions. Blocks of this type with a single central chamber are more fragile and subject to breakage during the manufacturing and shipping processes as well on the jobsite. The interlocking of the protrusions work well in a straight line but do not work effectively on corners.
U.S. Pat. No. 5,711,129 of Michael E. Woolford discloses a composite masonry block having a front surface and a back surface which are adjoined by first and second side surfaces, as well as a top surface and a bottom surface each lying adjacent to the front, back, and first and second side surfaces. Each of the side surfaces has an inset spanning from the block top surface to the block bottom surface. The block top surface has one or more protrusions positioned adjacent to the first and second insets on the block top surface. The blocks have back legs that are directed outwardly from the blocks back surface. The block back legs may extend in a plane parallel to the block front surface or extend forwardly toward the blocks front surface. In use, the blocks may be stacked to provide an interlocking structure wherein the protrusions of one block interfit within the insets of another block.
This patent discloses a composite masonry block that is designed specifically to be used in landscaping and would not function in the construction of masonry walls on structures. They are constructed for each coarse to step back from the preceding coarse for terracing and retaining walls.
U.S. Pat. No. 5,379,565 of Fabien Vienne additionally describes a block to be laid without mortar comprised of six faces opposite two-by-two and of which at least one face is punched so as to form open internal cells separated by walls, characterized in that said block comprises ribs and grooves which extend in parallel to the edges on at least two faces with a length at the most equal to the greatest dimension of said block as well as a transversal channel of V-shaped cross-section disposed perpendicularly between the longitudinal edge and said rib on the upper face of said block.
This patent describes a mortar free block that is recessed on the sides to interlock but has no internal means of interlocking and loses its interlocking capability on corners.
None of these previous efforts, however, provides the benefits attendant with the present invention. The present invention achieves its intended purposes, objects and advantages over the prior art devices through a new, useful and unobvious combination of method steps and component elements, with the use of a minimum number of functioning parts, at a reasonable cost to manufacture, and by employing readily available materials.
In this respect, before explaining at least one embodiment of the invention in detail it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement, of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the present invention.

SUMMARY OF THE INVENTION

The invention is defined by the appended claims with the specific embodiments shown in the attached drawings. Briefly stated, the present invention contemplates a novel system of construction using two basic configurations of block, an interlocking full sized block and an interlocking half sized block. As in all building blocks of this style, a variety of widths will be available. This system requires that the blocks must be laid in the upright position and cannot be inverted although they can be rotated end to end. In the preferred embodiment of the invention, the top edges of the full block will have a beveled surface to give the appearance of a mortar joint. The bottom surface of the full interlocking block is flat and parallel to the top surface. The flat end wall has an engagement tongue on one side edge and a receiver groove on the other side edge. A pair of knockout grooves are located on the inner surface of the flat end wall. By hitting between the knockout grooves with a hammer, an upper section of the flat end wall may be removed as a means to insert reinforcing bars. A center wall extends between the two side walls forming the first cell into a square configuration. Two internal locking members extend past the top flat surface of the interlocking block within the first cell. Two knockout grooves are formed into the center wall for the optional removal of the section for the insertion of a reinforcing bar. The open end wall is inset from the sidewall ends incorporating two internal locking members and a relief area as a means to insert a reinforcing bar. The second rectangular cell is created between the center wall and the open end wall. An engagement tongue is located along the end of one of the parallel sides with the receiver groove located along the end of the other parallel side so there is a dual tongue and groove engagement between two blocks even if one has been rotated one hundred and eighty degrees.
The Haener half interlocking block in the preferred embodiment of the invention has the top edges having a beveled surface. The bottom surface of the half interlocking block is basically flat and parallel to the top surface. The flat end wall has an engagement tongue on one of the side edges and a receiver groove on the other. Internal locking members are located on the internal sides extending past the top surface. The one side wall end has an engagement tongue and the other has a receiver groove that will mate with either end of the Haener interlocking full block when starting or terminating a coarse of blocks.
Rotating a block within a course, with the side wall ends abutting the side wall ends of a second block, provides a means where a single full interlocking block can be rotated within a course of blocks and the spacing between the interlocking members will remain the same as if the blocks were laid in line with no change to the structural integrity of the wall. By having a textured surface on one side and a smooth surface on the other side of the Haener interlocking full blocks and rotating the blocks as required, a pattern can be established on the surface of the structure.
The alternate embodiment of the Haener half interlocking block will not have the beveled edges representing a simulated mortar joint, but will have square edges on the blocks so that the wall structure will appear seamless.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

THE OBJECTS OF THE INVENTION

The object of this invention is to create a system that uses only two interlocking block components.
Another object of this invention is to create a system of mortar free interlocking blocks.
Another object of this invention is to create a system of interlocking blocks that are not fragile and subject to breakage.
Another object of this invention is to create a system of interlocking blocks that have two separate cells and a third cell when two blocks are set end to end.
Another object of this invention is to create a system of interlocking blocks where three separate cells per block can be filled with grout if desired.
Another object of this invention is to create a system where one or more blocks can be rotated end to end within a course without loosing the structural integrity of the wall.
Another object of this invention is to create a full interlocking block with grooved knockouts or depressions to allow reinforcing bars to run the full length of the structure.
Another object of this invention is to create a preferred embodiment of the interlocking block with a bevel on the upper side edges and a bevel on opposite sides of the ends creating an artificial mortar seam.
Another object of this invention is to create an alternate embodiment of the interlocking block without the bevel on the edges to create a seamless appearance to the wall structure.
Yet another object of this invention is to create an interlocking block with the end cell in a square configuration so as to have equal support from the interlocking members either when the blocks are laid in line or on corners.
A further object of this invention is to create a system of interlocking blocks for creating structures that can be laid up by laborers under the direction of a single block mason.
An even further object of the invention is to be able to create a stronger block structure than the conventional block and mortar method of construction.
A final object of this invention is to reduce the cost and time involved to create block structures.
With respect to the above description, before explaining at least one preferred embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement of the components or steps set forth in the following description or illustrated in the drawings. The various apparatus and methods of the invention are capable of other embodiments and of being practiced and carried out in various ways which will be obvious to those skilled in the art once they review this disclosure. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing of other devices, methods and systems for carrying out the several purposes of the present disclosed device. It is important, therefore, that the objects and claims be regarded as including such equivalent construction and methodology insofar as they do not depart from the spirit and scope of the present invention.
Further objectives of this invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and together with the detailed description, serve to explain the principles of this invention.
FIG. 1 depicts a perspective view of the interlocking full block.
FIG. 2 depicts a perspective view of the interlocking half block.
FIG. 3 depicts a top plan view of two interlocking full blocks with the open ends abutting.
FIG. 4 depicts a top plan view of the interlocking full block.
FIG. 5 depicts an end view of the open end of the interlocking full block.
FIG. 6 depicts an end view of the flat end of either the interlocking full or half blocks.
FIG. 7 depicts a top plan view of the interlocking half block.
FIG. 8 depicts an end view of the open end of the interlocking half block.
FIG. 9 depicts a top plan view of a typical corner stack of interlocking full or half blocks.
FIG. 10 depicts a typical side view of the interlocking full block.
FIG. 11 depicts a top plan view of the alternate embodiment of the interlocking full block without the bevel on the upper side edges or the opposite sides of the ends.
FIG. 12 depicts a top plan view of the alternate embodiment of the interlocking half block without the bevel on the upper side edges or the opposite sides of the ends.
For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in conjunction with the accompanying drawings which are incorporated in and form a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, wherein similar parts of the invention are identified by like reference numerals, there is seen in FIG. 1 a perspective view of the Haener interlocking full block 10A with two parallel rectangular sides 12 and 14. This system requires that the blocks must be laid in the upright position and cannot be inverted although they can be rotated end to end. In the preferred embodiment of the invention, the top edges 16 and 18 have a beveled surface 20. The bottom surface 22 of the full interlocking block 10 is basically flat and parallel to the top surface 24. The flat end wall 26 has an engagement tongue 28 on one side edge 30 and a receiver groove 32 on the other side edge 34. A pair of knock out grooves 36 are located on the inner surface of the flat end wall 26. By hitting between the knockout grooves 36 with a hammer, an upper section 38 of the flat end wall 26 may be removed as a means to insert reinforcing bars. A center wall 40 extends between the two side walls 16 and 18 forming the first cell 42 in a square configuration. Two internal locking members 44 and 46 extend past the top flat surface 24 of the interlocking block 10A within the first cell 42. The internal surfaces 48, 50, 52 and 54 of the cell 42 create a square cell, open at the top and bottom. Two knock out grooves 38 are formed into the center wall 40 for the optional removal of the section 56 for the insertion of a reinforcing bar. The open end wall 58 is inset from the sidewall ends 60 and 62 incorporating two internal locking members 64 and 66 and a relief area 68 as a means to insert a reinforcing bar. It must be understood at this time that the flat end wall 26, the center wall 40 and the open end wall 58 can all be configured with knockout grooves 36 or with relief areas 68 and still fall within the scope of this patent. The second rectangular cell 70 is created between the center wall 40 and the open end wall 58 with internal surfaces 72, 74, 76, and 78. An engagement tongue 80 is located along the end 60 of the parallel side 12 with the receiver groove 82 located along the end 62 of the parallel side 14.
FIG. 2 depicts a perspective view of the Haener half interlocking block 100A with two parallel rectangular sides 112 and 114. In the preferred embodiment of the invention, the top edges 116 and 118 have a beveled surface 120. The bottom surface 122 of the half interlocking block 100A is basically flat and parallel to the top surface 124. The flat end wall 126 has an engagement tongue 128 on the side edge 130 and a receiver groove 132 on the other side edge 134. Internal locking members 144 and 146 are located on the internal sides 148 and 152 extending past the top surface 124. The side wall end 160 has an engagement tongue 180 and the other side wall end 162 that has a receiver groove 182 that will mate with either end of the Haener interlocking full block 10A when starting or terminating a coarse of blocks.
By rotating a block within a course, with the side wall ends 60 and 62 abutting the side wall ends 60 and 62 of a second block illustrated in FIG. 3 provides a means where a single full interlocking block 10A can be rotated within a coarse of blocks, the spacing between the interlocking members 44, 46, 64 and 66 will remain the same as if the blocks were laid in line with no change to the structural integrity of the wall. By having a textured surface on one side and a smooth surface on the other side of the Haener interlocking full blocks 10A and rotating the blocks as required, a pattern can be established on the surface of the structure. Tapered locater 86 visible in this view is located on the internal surface 78 of the open end wall 58 and adapted in width to engage between underlying interlocking members 44, 46, 64 and 66 when the full blocks are stacked in a wall.
FIG. 4 depicts a top plan view of the Haener interlocking full block 10A emphasizing the shape of the first square sell 42 where the space A is equal to the space B creating a means by which the Haener full interlocking block 10A can be rotated ninety degrees to form a corner joint. In the parallel alignment of the Haener interlocking full blocks 10A the internal locking parallel pairs of members 44,46,64 and 66 make contact with the cell internal surfaces 48,52,72 and 76. When the one of the interlocking full blocks 10A and 10B are rotated at a corner internal locking members 44 and 46 make contact with internal surfaces 50 and 54 to maintain the same internal structural support at the corners.
FIG. 5 depicts an end view of the open end of the Haener interlocking full block 10A indicating the height C of the locking members 44,46,64 and 66 above the top surface 24 of the Haener interlocking full blocks 10A and 10B.
FIG. 6 depicts an end view of the flat end 126 of either the Haener interlocking full 10A or half blocks 100A with the half blocks 100A shown having the parallel side 112 and the opposite parallel side 114. The flat end wall 126 has a receiver groove 132 on the side edge 134 and an engaging tongue 128 on the side edge 130. The interlocking members 144 and 146 are illustrated extending past the top surface 124 that is parallel to the bottom surface 122.
FIG. 7 depicts a top plan view of the Haener interlocking half block 100A with the flat end wall 126 extending between the parallel side wall 112 and the parallel side wall 114. The interlocking members 144 and 146 are in the same relative position to the flat end wall 126 as the interlocking members 44 and 46 are to the flat end wall 26. The interlocking member 144 is located on the internal surface 148 and the interlocking member 146 is located on the internal surface 152. At the open end 156 of the Haener interlocking half block 100A, the side wall end 160 has an engaging tongue 180 while side wall end 162 has the receiver groove 182.
FIG. 8 depicts an end view of the open end 156 of the Haener interlocking half block 100A.
FIG. 9 depicts a top plan view of a typical corner stack of Haener interlocking full block 10A where the first cell 42 of the lower block aligns with the first cell 42 of the block above and the inter locking member is adjacent to the internal surface 50 and the locking member 44 is adjacent to the internal surface 54.
FIG. 10 depicts a typical side view of the Haener interlocking full block 10A illustrating the parallel side 12 with the flat bottom surface 22 and the interlocking members 44 and 64 extending above the top surface 24. A beveled surface 20 extends along the side top edge 16 and down the edge of the side wall 60.
FIG. 11 depicts a top plan view of the alternate embodiment of the Haener interlocking full block 10B without the beveled surface 20 on the upper side edges 16 and 18 or the ends 30 and 60.
FIG. 12 depicts a top plan view of the alternate embodiment of the interlocking half block 100B without the beveled surface 20 on the upper side edges 116 and 118 of the parallel sides 112 and 114, or the ends 30 and 60.
The interlocking block apparatus and method shown in the drawings and described in detail herein, disclose arrangements of elements of particular construction and configuration for illustrating preferred embodiments of structure and method of operation of the present invention. It is to be understood, however, that elements of different construction and configuration and other arrangements thereof, other than those illustrated and described may be employed for providing the disclosed interlocking block device and method in accordance with the spirit of this invention, and such changes, alternations and modifications as would occur to those skilled in the art are considered to be within the scope of this invention as broadly defined in the appended claims.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.

Claims

1. A two-block building system comprising:

a first block having a top surface, a bottom surface, two parallel sidewalls joined at a first end to an endwall, said sidewalls having distal ends opposite said first end;

said first block having a second wall extending between said sidewalls adjacent to said distal ends;

said first block having an open end cavity extending between said distal ends of said second wall;

a second block having a top surface, a bottom surface and two parallel sidewalls, said sidewalls attached at respective first ends to an endwall;

a plurality of projections extending above said top surface of said first block;

a plurality of projections extending above said top surface of said second block; and

recesses communicating with said bottom surfaces of said first and second blocks, said recesses positioned for an engagement with underlying of said projections from any of said first and second blocks, stacked to form a wall.

2. The two block building system of claim 1 additionally comprising:

said second block having a length substantially one half the length of said first block.

3. The two block building system of claim 1 additionally comprising:

each of said plurality of projections extending above said respective top surfaces having rectangular shape formed by four side surfaces; and

each of said recesses extending below said respective bottom surfaces having at least one engaging side surface positioned to contact at least one respective of said side surfaces of said projection, whereby said projections in said engagement within said recesses provides means to align respective sidewalls of overlying of said first and second blocks stacked in a wall, with underlying of said first and second blocks stacked in said wall.

4. The two block building system of claim 2 additionally comprising:

5. The two block building system of claim 1 additionally comprising:

one of said sidewalls of each of said first blocks having a projection extending along said distal end thereof;

the other of said sidewalls of each of said first blocks having a recess formed along said distal end thereof;

one of said sidewalls of each of said second blocks having a projection extending along said distal end thereof;

the other of said sidewalls of each of said second blocks having a recess formed along said distal end thereof;

said end wall of each of said first blocks having a projection extending therefrom positioned in-line with said recess at said distal end of said sidewall thereof;

said endwall of each of said first blocks having a recess formed therein, said recess positioned in-line with said projection extending from said distal end of the other of said sidewalls of said first block;

said endwall of each of said second blocks having a projection extending therefrom positioned in line with said recess at said distal end of said sidewall thereof;

said endwall of each of said second blocks having a recess formed therein, said recess positioned in line with said projection extending from the distal end sidewall of said second block; and

whereby said respective projections and said recesses upon said distal ends and said sidewalls of any one of said respective first or second blocks, engages with mating of said recesses and said projections formed upon any first or second block placed adjacent thereto.

6. The two block building system of claim 2 additionally comprising:

said endwall of each of said first blocks having a recess formed therein positioned in-line with said projection extending from said distal end of said sidewall thereof;

said endwall of each of said second blocks having a recess formed therein, said recess positioned in-line with said projection extending from said distal end of sidewall thereof; and whereby said respective projections and said recesses upon said distal ends and said sidewalls, of any one of said respective first or second blocks, engages with mating of said recesses and said projections formed upon any first or second block which placed adjacent thereto in forming a wall.

7. The two block building system of claim 3 additionally comprising:

8. The two block building system of claim 4 additionally comprising:

9. The two block building system of claim 1 additionally comprising:

said first block having a recess formed in a center portion of said second wall adjacent to said top surface;

said first block having a third wall extending between said sidewalls in between said endwall and said second wall;

said first block having a first cavity defined by an area between said endwall, said sidewalls, and said second wall;

said first block having a second cavity defined by an area between second wall, said sidewalls and said third wall;

a central portion of said endwall communicating with said top surface of said first block being frangible;

a center portion of said third wall communicating with said top surface being frangible; and

whereby said center portion and said central portion when removed align with said recess thereby proving a horizontal path of communication through said first block, whereby reinforcing bar or conduit may be communicated through said horizontal path when said first blocks are adjacently engaged in a wall.

10. The two block building system of claim 1 additionally comprising:

11. The two block building system of claim 6 additionally comprising:

12. The two block building system of claim 7 additionally comprising:

said first block having a first cavity defined by an area between said end wall, said sidewalls, and said third wall;

13. The two block building system of claim 8 additionally comprising:

14. The two block building system of claim 5 additionally comprising:

15. The two block building system of claim 3 additionally comprising:

a plurality of projections extending above said top surface of said first block being four; and

said plurality of projections extending above said top surface of said second block being two.

16. The two block building system of claim 7 additionally comprising:

17. The two block building system of claim 12 additionally comprising:

a plurality of projections extending above said top surface of said first block being four projections formed in two parallel pairs; and

a first of said parallel pairs extending from said second wall, each of said first pair having one side surface adapted to contact an inner surface of a respective sidewall of an overlying first or second block forming said wall, each of said second pair having one side surface adapted to contact an inner surface of a respective sidewall of an overlying first or second block forming said wall, whereby overlying blocks engage with said projections of underlying blocks whether said overlying blocks are parralel or normal to said underlying blocks.

18. The two block building system of claim 4 additionally comprising:

a first of said parallel pairs extending from said second wall, each of said first pair having one side surface adapted to contact an inner surface of a respective sidewall of an overlying first or second block forming said wall, each of said second pair having one side surface adapted to contact an inner surface of a respective sidewall of an overlying first or second block forming said wall.

19. The two block building system of claim 8 additionally comprising:

20. The two block building system of claim 13 additionally comprising:

21. The two block building system of claim 19 additionally comprising:

said first block having a ledge extending from said second wall into said second cavity of said first block; and

said ledge having a width dimension adapted to engage interior side surfaces formed on said first or second parallel pairs of projections of underlying first blocks in a wall formed of stacked first blocks.

22. The two block building system of claim 20 additionally comprising:

23. The two block building system of claim 4 additionally comprising:

24. The two-block building system of claim 1 additionally comprising:

said two sidewalls of said first block having exterior surfaces with one of said exterior surfaces being textured and the other of said exterior surfaces being smooth;

said two sidewalls of said second block having exterior surfaces with one of said exterior surfaces being textured and the other of said exterior surfaces being smooth; and

whereby a side surface of a wall built with said first or second blocks may have a textured or smooth surface by rotation of said first and second blocks.

25. The two-block building system of claim 1 additionally comprising:

26. The two-block building system of claim 7 additionally comprising:

27. The two-block building system of claim 8 additionally comprising: