Suggested Directions to Build
a VOBB wall and/or whole building

Index I. Suggested directions     II. Additional tips to avoid mistakes and wasted time III. Suggested tools to be used for building a typical VOBB home/building IV. Ordering VOBB from the block plant V. Certification as VOBB quality VI. VOBB / concrete block rules

2. Place rebar in the foundation (for the exterior VOBB walls) before the concrete cures on a vertical basis for insertion in the VOBB blocks. This placement of rebar is suggested to be approximately every four linear feet. The rebar must be placed so that it aligns with the cavities of the VOBB block. (Do not put rebar where it will interfere with doors or windows.) The rebar should extend above the foundation by at least two foot. (It greatly helps to use a string to place the rebar so that the row of rebar is straight and that the rebar will properly fit into the cavities of the VOBB block.)

For a web page just of rebar, please see:
http://www.vobb.com/rebar.htm

3. Prepare to begin to dry-stack the VOBB blocks by marking off all walls with a chalk-line, or other marker. Make all VOBB utility blocks by cutting out for the electrical, gas and water outlets as needed. These cuts can be made with an electric saw using a concrete blade. There should be a few extra units made so that the VOBB block can be properly placed depending on which cavity has been cut out for the electrical box, etc. For lintels above the doors and windows, either drill a one-inch hole or cut a opening on a horizontal basis in the necessary VOBB blocks to place the rebar. The proper door and window frames should be available before any VOBB blocks are dry-stacked. (The people who have not followed this procedure, have learned the hard way that once the grout is dry, it is very difficult to change. Do it right the first time BEFORE the grout is poured into the cavities.)

The contractor must stay on the job as the workers go so fast that they will stack VOBB where the doors and windows are.

Putting in the window frames

 

Putting in an electrical box

4. Stack one row or two rows of VOBB block for the entire area where the wall is to be built. (Note that the VOBB blocks are "mathematically" correct in that all wall components must be in units of less than six inches. The walls, doors and windows must be in increments of six inches such as three feet or three feet and six inches, etc.) There will be some vertical space between the VOBB blocks. This is the expansion gap. The important thing is that the corner blocks and doors and windows are properly placed in accordance with the plans. For example, if a wall is to be ten feet long, then the outside end of each corner block must be EXACTLY ten feet apart.

The first row of VOBB blocks is laid out for the entire home to mark the doors and corners. It is STRONGLY recommended to lay out the exterior walls before doing any interior walls. Do all four corners first.

Dry-stacking the first two rows

5. Stack the VOBB blocks at each corner, wall intersection, door or window opening on a stair-step basis up about three feet. (This depends on the height of the wall and what is easiest for the workers. This suggestion is based on experience. The wall needs to be straight. As such, the corner are very important to get straight.) All blocks must be checked to be sure that they are level on a vertical basis. The VOBB blocks are held together (end-to-end) with the use of VOBB clips. The VOBB clips are only used temporarily to hold the blocks together/aligned. When the concrete/mortar is put into the cavities of the VOBB blocks, the blocks then become attached on a permanent basis.

For a picture of a perfect corner (starting point), please see:

http://www.vobb.com/construction-photos/LA-Labauve/Labauve-corner-a-2003-June.jpg
or

http://www.vobb.com/construction-photos/LA-Westbrook/Westbrook-day-1-corner-2.jpg

A perfect VOBB corner - always do the corner first to have a straight wall

 

 Putting in a VOBB clip      

 

One VOBB at a time

6. Place rebar in the applicable cavities (on a vertical basis) allowing the rebar to exceed the height of the wall by one foot or so. Pour concrete/grout into the applicable cavities to permanently attach the blocks to the foundation. Be careful not to spill concrete/grout on the top of the blocks, which would cause the blocks on top to stack unevenly. Concrete/grout should be poured in all corners and intersecting cavities. All six-inch blocks must have concrete/grout poured into them. Concrete/grout should be poured into all of the block cavities adjacent to the doors and windows and at all corners. Pour concrete/grout into the VOBB block cavities on an alternating basis, thus allowing for placement of the electrical, plumbing, etc.

The black tape (or red paint) is to mark where the rebar is located. It is easy to lose sight of the rebar once the VOBB blocks have been stacked up. We recommend to stack the VOBB block with the rebar showing at least one foot and then to pour in the grout.

After several trials, it has been successful proven that the easiest method with less waste, is to use bag concrete mix with pea gravel. The blocks should be soaked with water on both the inside and the outside. Then, the concrete mix should be poured into a 3-5 gallon bucket with a lip on it. This dry concrete mix is then poured into the block cavities at the same time another person sprays in water directly into the VOBB block cavity. The concrete mix is then stirred and allowed to settle. Additional mix is added as needed. This procedure will save a tremendous amount of time and there is no need for a pump or for a concrete mixer. Without a doubt, this method works as there is no mortar joint. Some water will run out the sides which can be cleaned with water. Do not fill the cavities to the top unless it is the top row.

Pouring in the cement mix - DRY - THIS IS A BIG TIME AND LABOR SAVING METHOD!!!!

After the mix and water is in, just stir with some rebar to settle the mix.

It is is much easier and cheaper to mix in the water using a water hose with a nozzle vs. mixing the cement mix

Keith is pouring in dry concrete with pea gravel mix. Water is added as it is poured in for a very cost-effective and simple method. It is very important to wet the VOBB blocks before and after if this method is used.

or, the more traditional method is to premix the grout:
Pouring in grout     

Do NOT fill the grout to the top of the block as this will create a break-line. Rather, only fill up to approximately three inches from the top of the block such as the following:
Fill only to the middle with grout. Do not fill the cavity to the top so that the next pour will allow for a good setting

 

7. After the concrete/grout dries, the blocks can be filled between the two stair-step points to an even height. All VOBB blocks must be placed in the proper position so that the wall is straight – i.e. use of a level is required. Blocks with cut-outs for the electrical, telephone, etc. should be placed as called for in the building plans. Care should be used so that the placement of these outlets are properly aligned with the pouring of concrete/grout, i.e. do NOT put an electrical box in the same cavity as where the concrete/grout is poured, unless conduit is used FIRST. It is good to use a string to be sure the wall is straight.

Using a string to be sure the wall is straight.

 

8. Continue with steps 5, 6 and 7 until the proper wall height is achieved.

9. VOBB blocks with a one-inch horizontal hole through the VOBB block will be used to insert one-half inch rebar to make the VOBB lintels above the doors and windows. The door or the window VOBB frame will need to be properly placed and leveled to support the lintel until the concrete dries. (Otherwise, supports holding the blocks in place will need to be made until the concrete has dried.) Concrete/grout should be poured/pumped into all of the VOBB block cavities above the doors and windows to give a "permanent" fixture. For a door with a eight foot wide opening, it is suggested to use two rows of VOBB lintels. For a door more than 15 feet wide, it is suggested that you use three rows of VOBB lintels.

For a web page just of lintels, please see:
http://www.vobb.com/lintels.htm

 

10. After the last row of VOBB blocks have been added, after the final pumping/pouring of concrete/grout in the VOBB blocks (but before the concrete/grout dries), place an anchor bolt in the VOBB cavities about four or six feet apart to fasten down the top-plate.

 

11. While custom door frames with VOBB grooves on the back side can be made, at this time due to low volume, we find that is not required/necessary to use VOBB door frames. A simple door frame which is square and straight will work. (In the future with more volume production, we will work to have custom VOBB door frames built.)

For a sample of special VOBB door frames:
The door frame has VOBB grooves to attach the VOBB block to the frame

    This is an example of stacking VOBB blocks while a door frame is put in its proper place.

 

A door frame can be made very easily to attach to the VOBB block. It is suggested to use a 2" * 8" and trim it to an exact width of six inches. On the back side two grooves should be made for the VOBB clips to be inserted. These grooves should be three inches from the exact center. They grooves should be one-half inch deep. The angle should be 50 degrees. The neck width should be .375 inch and the back should be .875 inch wide.

We suggest to put the door and window frames in at the same time as the VOBB block are dry-stacked. This is to be sure the door frame and window is straight and level before the grout is poured/pumped into the block. It is important that the door and window frame are the correct size or it will be a very BIG mess if the opening is the wrong size.
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If you would like to see some engineer drawings of the foundation used for building a VOBB home, click here.     engineer-drawings/index.html

For each eight feet (16 cavities), a 80 lb. bag of concrete mix with pea gravel is required. This is in effect 10 lbs. for each foot or two cavities.

Note:   For very simple installation, concrete mix (with pea gravel) can be poured directly from the bag (or a bucket) into the VOBB block cavities. This is because no mortar mix is needed and the VOBB blocks sit right on top of each other. Water, in the appropriate amount, can be sprayed directly into the VOBB block cavities with the concrete mix. This is a tremendous time and money saver, i.e. the mix does NOT need to be mixed prior to putting it into the VOBB block cavities. Be sure to wash down the outside and top of any excess. This is a great way to make up the lintels and for small jobs. The mix can be stirred directly in the cavities with a piece of rebar to ensure a uniform mix. (You may have to try this method to fully realize the effectiveness and time savings.)

 

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II. Additional tips to avoid mistakes and wasted time:

VOBB blocks are made for the structure to protect the people in the building from storms, fires and to prevent termites from eating the walls. VOBB block require an exterior "skin" of brick, stucco, sheetrock, panels, etc. to make the building look pretty. VOBB blocks have built-in expansion gaps on a horizontal basis to allow the block to expand with the daily heat and cold. Due to nature of making VOBB blocks at a high rate of speed of thousands per hour, VOBB blocks are not 100% even. The only way to get 100% even on the top is to grind the blocks. This generally cost one dollar per block for grinding and people do not want to pay this extra cost. As such, when needed, shims are used to keep the wall level on a vertical basis. We are changing the industry in that we measure our VOBB blocks in thousands of an inch.

Use shims when needed to get a level wall on a vertical basis.

Use adjustments as needed at the top plate

The top plate is fastened with the use of an L-bolt.

Below is the link from an independent engineering company measuring the VOBB blocks.http://www.vobb.com/manufacturers/TX-Davids-Patio
/Davids-Patio-measurement-test.pdf

 

Rub a piece of VOBB block on top of the VOBB on the pallet to be sure the tops have no ridges. Pull the VOBB off of the pallet. Do not lift the VOBB as the pulling also helps to make sure the VOBB blocks are smooth on the top.

Fastenal Grinder to remove high spots (approximate cost $60 to $70)

 

Or you can buy one from Lowe's for approx $20.

 

 

1. Unless you have a forklift and/or a lot space, the VOBB blocks should only be sent to the job-site AFTER the foundation is poured and hardened. Lines should be marked where the walls are to be placed so that the VOBB blocks can be arranged to be set on the foundation in an efficient basis. Likewise, it is suggested not to drive a forklift on the foundation unless it has fully cured and it was designed for such a load.

2. The VOBB blocks should be set on the foundation on pallets so that the VOBB blocks can be easily moved via a pallet jack. VOBB blocks can be set on the ground on the outside of the foundation to be used first for the exterior walls. The key to cost efficiency is not to move the VOBB blocks but one time on a manual basis; from the pallet to the wall. When placing the VOBB blocks on the foundation, make sure that there is open space left to work and for the use of a scaffold/ladder as needed.

3. All cutouts of VOBB blocks for electrical and plumbing should be completed before starting to stack the VOBB blocks. (It may be best to make some extra electrical cutouts due to breakage, etc.) VOBB blocks which are to be used for the "lintels", should be drilled via a one inch bit before starting to stack the VOBB blocks also. These "lintel" VOBB blocks should be placed over each and every door and window opening. A rebar on a horizontal basis should be inserted ASAP. For VOBB lintels, make sure that they are made at least one foot longer then the width of the door or window (e.g. a door which is three feet wide, the VOBB lintel should be four feet long). This extra length allows for overhang on the wall.  If the VOBB block are going to be pre-made, then make the lintels on day "one" of the job by pumping/pouring the concrete slurry into the VOBB blocks. They can then be fitted into the proper setting as required on day "two" and "three".

Putting in an electrical box

We strongly suggest to use the electric boxes which have a lip on the top and bottom. This is so that the electric box will not "fall" into the block cavity. Also, we suggest to use the electric boxes which are deep to make it easy to run the wires or use conduit. The local building code may specify whether the plastic or the metal electrical boxes should be used.

As an alternative, the electrical wires (subject to local build code approval) can be strung on the outside of the VOBB block and a thin electrical box can be used between the VOBB block and the sheetrock.

 

This is a thin electrical box nailed to the VOBB block

Some people prefer to use flexible conduit vs. the hard conduit. It is the owner's choice, subject to local building code.

              

Electrical conduit for closet light        Full height of wall with flex conduit

 

4. The location of ALL electrical and plumbing requirements should be marked on the foundation PRIOR to stacking any VOBB blocks.

5. With the proper size crew (a supervisor and a crew of four helpers), a typical one-story 2,500 sq. ft home (with nine-feet high walls) should have the VOBB blocks stacked in three to seven work-days. This depends on having the all material and tools on hand. On Day 1, stack the corners out (up to 1/2 of the height of the typical 9 or 10 foot wall) and where the doors and windows are to be placed. The VOBB blocks cavities should be filled with grout as applicable: alternate filling the cavities but fill all cavities in the VOBB blocks at the corners and next to the door and windows. On Day 2, the blocks between the corners should be filled in (stacked) and the balance of the height of the first floor should be stacked and grout poured to dry over night. On Day 3, fill in (stack) the balance of the VOBB blocks to the proper wall height.

Note: Due to the ease of dry-stacking VOBB, if the supervisor (who knows the floor plan/design) is not on the job at all times, we have found that the helpers will stack the VOBB where windows should be placed, leave out the VOBB blocks cut for the electrical, will not use the level to check the straightness of the wall, etc. etc. As such, the supervisor should be on the job at ALL times.

6. If a six-inch VOBB blocks is used, it must be stacked where the grout will be pumped/poured into the cavity. As an alternative, rather than using one 18-inch and one six-inch VOBB block, use two 12-inch VOBB blocks.

7. If a VOBB block needs to be cut for a 45 degree angle, etc., then a vertical support should made to allow the grout to be poured/pumped down these cavities to have a permanent connection. (i.e. nail a board to the wall to cover where the grout is to be poured/pumped.)

8. When pouring/pumping the concrete into the cavities, only fill the top VOBB block up one-half, unless it is the very top row. You do not want to spill any concrete on top of the VOBB blocks as the next layer will not stack properly.

Before starting the job or pouring or pumping the cavities with the concrete grout, we strongly suggest to mark the block (with paint, tape, etc.) where to pour or not to pour. Likewise, the rebar coming out of the foundation should be marked as when the VOBB block are dry-stacked, these rebar become "hidden".

8. All waste and seepage should be carefully washed down IMMEDIATELY after pouring/pumping in the concrete into the VOBB blocks.

9. There should be two anchor bolts for the top plate at each corner wall. They should be placed so that one anchor bolt is in each top plate. For simplicity, do not use the corner, rather use the adjacent cavities on both sides. Thereafter, space the anchor bolts in accordance with the building code (or it is suggested every four feet). Make sure these anchor bolts are ready on-site to be inserted before the concrete is poured/pumped into the top row of the VOBB blocks. We recommend that these anchor bolts be at least 18 inches long and one-half inch in diameter. This size may need to be increased due to special local building code requirements.

Suggested L-bolts to fasten the top-plate to the VOBB wall.

An 18-inch "L" bolt to anchor the top plate to the VOBB block

The "L" bolt is put in the top VOBB blocks on as vertical basis

10. The first vertical rebar should be placed in the foundation (before the concrete dries) based on a bull's-eye center of a six-inch VOBB block.  That is the rebar's center should be three inches from the both sides. From there, it is "suggested" to have vertical rebar inserted in the foundation every four feet. We recommend that rebar which is at least 1/2 inch in diameter be used and that the rebar be at least six inches deep in the foundation. If you have any doubts, contact an experienced building engineer.

 

1	2	3	4

5	6	7

 

At a corner, a VOBB is in effect a six-inches square. As such, one half is three inches.    It is suggested that the rebar be at least two feet out of the foundation, but could be four feet high.    

X

(This should be a six-inch by six-inch square with an "X" in the center to mark the bull's eye.)  

11. It has been "suggested" that for the mix of the grout when using a pump, to use the following:
(There should an eight inch or ten inch slump.)

A.  600 pounds of cement
B.  750 pounds of 3/8" or 1/2" pea aggregate/gravel
C.  2,000 pounds of sand

12. It has been suggested by a building contractor to make the footing two feet wide and two feet deep for construction which is two stories tall.  The proper rebar as per the local code should be used.    It is suggested that this rebar be at least six of the # 5"s (1/2 inch) or four of the # 6's (5/8").  Again, if in doubt, check with an experienced engineer or the local building inspector.

13. A construction site which has the trash picked up and the tools kept organized on a daily basis, is a much safer work place. A construction site with trash laying around is an accident waiting to happen.

14. If wood is used as a top-plate or is bolted to the sides of the VOBB block for support for the trusses, we recommend to use treated wood. (In some areas, the building code actually requires the use of treated wood next to CMU.) This is because CMU is like a sponge and soaks up moisture. As such, the moisture may then travel to the wood.

15. When brick is put up on the exterior, the brick-tie should be nailed into the VOBB (and through the insulation if applicable) and then the brick tie can be positioned so that it will be in the mortar joint. NOTE: IF THE INSUALTION IS ON THE EXTERIOR, EXTRA LONG NAILS SHOULD BE USED FOR THE BRICK TIES. IF NOT, THE THE NAIL WILL ONLY GO INTOP THE INSULATION AND NOT INTO THE BLOCK WHERE IT WILL BE SECURE.

Use metal I-beams when in a high wind or hurricane surge area.

 

Use horizontal rebar as per qualified engineer or architect specs.

 

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III. Suggested tools for building a typical VOBB home/building:
1. A level for each person (the longer, the better)
2. Chalk string and plenty of mason string
3. Small rubber mallet for each person - The handle should be trimmed as necessary to be used to push the VOBB clips into the VOBB blocks
4. Nail apron for each person to carry the VOBB clips
5. To make the VOBB lintels, a good drill with a one inch bit 12 inches long
6. To cut the electrical, water or gas outlets, a electric saw with a concrete blade
7. A pallet jack to move the pallets
8. Several good stepladders
9. Scaffold with wheels - the more scaffolds, the less moving
10. A good chop saw or other tool to cut the rebar
10. A samll grinder with diamond wheel to remove high spots.
12. For very large jobs, a small concrete pump with a two and a half-inch or a two-inch hose to pump the concrete into the cavities (It is strongly recommended not to use a pump with a large four inch hose as there is a lot of waste and it difficult to move the hose.)This is a picture of a sample Mayco pump.

However, we now recommend to avoid the cost of a pump and just pour in the concrete mix at the same time water is sprayed into the block cavities. This concrete is then mixed using a piece of rebar for a simple and cost efficient method.

12. Water hose with a good nozzle to wash down the spillage - this hose needs to reach the full length of the building.
13. Electric extension cords
14. A forklift or other lifting device, especially if the building is two stories tall

15. A "concrete" nail gun. A sample nail gun which we have found to be very affective is a TrakFast, Model NO. TF1100.           (See our suggested list of Manufacture for ordering.)

16. A grinder to even out high spots on the VOBB block.
Fastenal for approx $70

At Lowe's for approx. $20

If you do not own the tools listed above, then we strongly recommend you rent them for the duration of stacking the VOBB for an efficient and safe job performance. We can not over emphasize the importance of safety. Eighty percent of all accidents are a result of unsafe acts and twenty percent of all accidents are a result of unsafe conditions.

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IV. Ordering VOBB from the block plant
1. To place an order for VOBB block, it is necessary to the calculate the wall surface (if you don't use a design program which will automatically calculate the materials list).
2. As an 18-inch VOBB equals 3/4 of a square foot in wall surface area (6" high by 18" long), then a ten foot by ten foot wall surface area (100 sq. ft.), would require a theoretical 133 of the 18-inch VOBB.
3. As no wall will use only 18-inch VOBB's (without knowing the exact floor plan), for a 'typical" home we estimate 83% of the order (square feet area) will be 18-inch VOBB, 11% will be 12-inch VOBB, and 6% will be 6-inch VOBB.
4. We recommend to order an extra 2% to 10% of VOBB as a precaution due to breakage or change in plans. (These extra VOBB's tend to become used for other projects such as landscaping, building steps, special projects, etc.).
5. Attached is Excel spreadsheet for the work-up of
an order for 10,368 VOBB.

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V. Certification of construction as VOBB quality

1. All interior and exterior walls must use VOBB block.
2. All corners must have the three adjoining cells filled with grout using pea gravel.
3. All intersecting walls must have the four adjoining cells filled with grout using pea gravel. Thereafter, the cells need to be grouted only on an alternating basis, but they can be grouted in every cell due to building basements, in earthquakes area, for tall buildings, etc.
4. Wherever grout is used, a piece of rebar must be used inside the cavity. (Minimum of 3/8", but for most full-size buildings it is strongly recommended at least 1/2"). In areas of high wind (tornadoes or hurricanes), wind sure or ear ht quakes, you should consider to use vertical rebar, to use 6" I-beams in the door/window lintels/headers and to use one-inch rebar.
5. Rebar placed in the foundation must be used in all four exterior walls corners, protruding at least two feet tall above of the foundation, and used thereafter at least every four feet on a linear basis. (Minimum 1/2" rebar)
6. For the top row of the VOBB block, an 18" long (1/2" diameter) J-bolt (or regular bolt with a large head/washer) must be used to post tension the VOBB blocks to the top-plate. These J-bolts are required in every corner and on a linear basis every four feet thereafter.

VI. VOBB / concrete block rules

1. If the wall is not straight "BEFORE" you pour in the grout, it will not be straight "AFTER" you pour in the
grout.
2. The most important tool is the level.
3. VOBB blocks are made for structure to protect your family, business, etc. and for the finished project to be affordable. VOBB blocks are not made for looks. You will need to put up some covering (brick, sheet rock, stucco, siding, etc.) to make the building/wall look "pretty".
4. Concrete block absorb water like a "sponge".

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Due to numerous different soil conditions, building codes, etc., VOBB makes no guarantees and/or warranties (expressed or implied). Please contact a qualified engineer, architect or building inspector as needed.