SECTION 03 20 00

CONCRETE REINFORCEMENT - VOID FORMERS

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PART 1    GENERAL
1.1	SECTION INCLUDES
A.	Void formers and accessories for concrete slabs.
B.	Single-concrete placement installation. 
C.	Double-concrete placement installation. 
1.2	RELATED SECTIONS
A.	Section 03 11 00 - Concrete Forming and Accessories.
B.	Section 03 30 00 - Cast-in-Place Concrete.
1.3	REFERENCES
A.	ASTM International (ASTM):
1.	ASTM A615 - Standard Specification for Deformed and Plain Carbon Steel Bars for Concrete Reinforcement.
2.	ASTM E119 - Standard Test Methods for Fire Tests of Building Construction and Materials. 
B.	CRSI Design Guide for Vibrations.
C.	Clean Products Action (CPA):
1.	GreenScreen Score: LT-P1. 
D.	2021 International Building Code (IBC).
E.	International Organization for Standards (ISO):
1.	ISO 14021 - 1999 - Environmental Labels and Declarations - Delf-Declared Environmental Claims Type II, Environmental Labeling.
2.	ISO 14024-2006 - Environmental Labels and Declarations - Type III Environmental Declarations - Principles and Procedures.
3.	ISO 14025-2006 - Environmental Labels and Declarations - Type III Environmental Declarations - Principles and Procedures. 
4.	ISO 14040-2006 - Environmental Management - Life Cycle Assessment - Principles and Framework. 
5.	ISO 14044-2006 - Environmental Management - Life Cycle Assessment - Requirements and Guidelines.
6.	ISO 14067-2018 - Greenhouse Gases - Carbon Footprint of Products - Requirements and Guidelines for Quantification.
7.	ISO 17050-2008 - Conformity Assessment - Suppliers Declaration of Conformity. 
8.	ISO 21930-2017 - Sustainability in Buildings and Civil Engineering Works - Core Rules for Environmental Product Declarations of Construction Products and Services. 
F.	U.S. Green Building Council (USGBC).
1.4	SUBMITTALS
A.	Submit under provisions of Section 01 30 00.
B.	Sustainable Design Submittals: 
1.	GreenScreen Assessment: Assessment results. 
2.	Cradle to Grave Environmental Product Declaration (EPD): Type III: Details of third party certification and product category rules clearly stating scope, declared units, system boundary and environmental impact category assessed.
3.	Cradle to Gate Environmental Product Declaration (EPD): Type III: Details of third party certification and product category rules clearly stating scope, declared units, system boundary and environmental impact category assessed.
C.	Product Data:
1.	Distributor's data sheets on each product to be used.
2.	Preparation instructions and recommendations.
3.	Storage and handling requirements and recommendations.
4.	Typical installation methods.
D.	Verification Samples: Furnish two sample units required for the project of each void former type. 
E.	Structural Drawings: Include details of materials, construction, and finish. Include relationship with adjacent construction.
F.	Placement Drawings: Placement Drawings will be furnished by the void former distributor and include dimensions, locations, spacing requirements and quantities for each void shown on the Structural Drawings. 
1.	Quantity of concrete to be displaced by void formers for each area will be indicated on each Drawing. 
2.	Placement Drawings will include installation instructions for handling and placement of void formers, as well as instructions for placement of concrete. 
1.5	QUALITY ASSURANCE
A.	Manufacturer Qualifications: Company specializing in manufacturing products specified in this section with a minimum of five years documented experience.
B.	Source Limitations: Provide each type of product from a single manufacturing source to ensure uniformity.
C.	Mock-Up: Construct a mock-up with actual materials in sufficient time for Architect's review and to not delay construction progress. Locate mock-up as acceptable to Architect and provide temporary foundations and support.
1.	The intent of a mock-up is to demonstrate quality of workmanship and visual appearance.
2.	If the mock-up is not acceptable, rebuild the mock-up until satisfactory results are achieved.
3.	Retain mock-up during construction as a standard for comparison with completed work. 
4.	Do not alter or remove mock-up until work is completed or removal is authorized.
1.6	PRE-INSTALLATION CONFERENCE
A.	Convene a conference approximately two weeks before scheduled commencement of the Work. Attendees shall include Architect, Contractor, trades involved and void form distributor. Agenda will include schedule, responsibilities, critical path items, approvals, system requirements applicable to the Project, coordination of void former installation with reinforcement installation and placement of concrete with placement of void formers.
1.7	COORDINATION
A.	Coordinate the Work of this Section with the Work of Sections 03 11 00 - Concrete Forming and Accessories, and 03 30 00 - Cast-in-Place Concrete. 
B.	Structural Engineer to coordinate with distributor to verify void type required to support shoring and point loads. 
1.8	DELIVERY, STORAGE, AND HANDLING
A.	Deliver void formers to site in distributor's protected packaging. 
B.	Protect from damage due to direct sunlight, weather, excessive temperature, and construction operations. Avoid stacking beyond distributor's recommended heights to prevent deformation. 
C.	Inspect all void formers upon delivery for damage. Reject damaged units. 
1.9	WARRANTY
A.	Manufacturer's Standard Limited Warranty: Manufacturer warrants that materials will be free from defects and fit for intended purpose, and will replace repair, or correct any defective materials for manufacturer's portion of work provided notice is given withing 30 days of delivery of materials. 
1.	Warranty Period: 1 year from the date of delivery. 
PART 2    PRODUCTS
2.1	MANUFACTURERS
A.	Acceptable Distributor: Cobiax USA, Inc, which is located at: 90 Pleasant Street, Dedham, MA 02026; Tel: 781-381-0111; Fax: 781-381-0199; Email: mmota@cobiaxusa.com Web: www.cobiaxusa.com .
B.	Substitutions: Not permitted.
C.	Requests for substitutions will be considered in accordance with the provisions of Section 01 60 00.
2.2	DESIGN AND PERFORMANCE REQUIREMENTS
A.	Performance Requirements: 
1.	IBC 2021: 2 hour unrestrained assembly rating for floors and roofs as tested according to ASTM E119. 
2.	GreenScreen: Product contents 100 parts per million. 
3.	LEED V 4.1: MR Credit: Building Product Disclosure and Optimization - Material Ingredients, Option 1. 
4.	LEED V 4: Building Design and Construction. 
B.	Design Requirements: 
1.	Void former layout must be detailed as such that spacing is maintained and of sufficient strength to support normal foot traffic and reinforcing bars. 
2.3	VOID FORMERS
A.	Basis of Design: CLS-V-3. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 17 psf (83.00 kg m2). 
b.	Shear Factor: 0.45. 
c.	Stiffness Factor: 0.96. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 1.76 lbs sq ft (8.60 kg m2). 
2.	Design Requirements: 
a.	Volume Displacement: 0.11 cf sq ft (33.5 mm).
b.	Support Void Height: 3.54 inch (89.9 mm). 
c.	Nominal Slab Thickness, No. 5 T and B: 8 inch (203.2 mm). 
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-1.5. 
f.	Half Shell Type: Bottom: CLS-H-1.5.
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 0.44 cu ft (0.012 m3) per piece.
j.	Percentage of Concrete Displaced: 16.5 percent. 
k.	Weight Per Void: 4.0 lbs (1.81 kg).
B.	Basis of Design: CLS-V-4.5. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 26 psf (126.94 kg m2).
b.	Shear Factor: 0.45. 
c.	Stiffness Factor: 0.94. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 2.05 lbs sq ft (10.01 kg m2). 
2.	Design Requirements: 
a.	Volume Displacement: 0.17 cf sq ft (5.18 cm).
b.	Support Void Height: 4.72 inch (119.9 mm). 
c.	Nominal Slab Thickness, No. 5 T and B: 9 inch (228.6 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-3. 
f.	Half Shell Type: Bottom: CLS-H-1.5.
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 0.68 cu ft (0.0193 m3) per piece.
j.	Percentage of Concrete Displaced: 22.7 percent. 
k.	Weight Per Void: 4.5 lbs (2.04 kg).
C.	Basis of Design: CLS-V-5.5. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 32 psf (156.24 kg m2).
b.	Shear Factor: 0.44. 
c.	Stiffness Factor: 0.93. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 2.46 lbs sq ft (12.02 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.21 cf sq ft (6.40 cm). 
b.	Support Void Height: 5.51 inch (140.0 mm). 
c.	Nominal Slab Thickness, No. 5 T and B: 10 inch (254.0 mm). 
d.	Recommended Aggregate Range: 1/2 to 3/4 (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-4. 
f.	Half Shell Type: Bottom: CLS-H-1.5.
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2). 
i.	Void Volume: 0.84 cu ft (0.0238 m3) per piece.
j.	Percentage of Concrete Displaced: 25.2 percent. 
k.	Weight Per Void: 4.6 lbs (2.09 kg).
D.	Basis of Design: CLS-V-6. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 33 psf (161.12 kg m2). 
b.	Shear Factor: 0.44. 
c.	Stiffness Factor: 0.93. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 2.87 lbs sq ft (14.03 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.22 cf sq ft (6.70 cm).
b.	Support Void Height: 5.91 inch (150.1 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 10.5 inch (266.7 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-3. 
f.	Half Shell Type: Bottom: CLS-H-3. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2). 
i.	Void Volume: 0.88 cu ft (0.0249 m3) per piece.
j.	Percentage of Concrete Displaced: 25.1 percent. 
k.	Weight Per Void: 4.9 lbs (2.22 kg).
E.	Basis of Design: CLS-V-7. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 39 psf (190.41 kg m2).
b.	Shear Factor: 0.44. 
c.	Stiffness Factor: 0.91. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 3.48 lbs sq ft (17.01 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.26 cf sq ft (7.90 cm).
b.	Support Void Height: 6.69 inch (17.00 cm). 
c.	Nominal Slab Thickness, No. 5 T and B: 11 inch (279.4 mm). 
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-4. 
f.	Half Shell Type: Bottom: CLS-H-3. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2). 
i.	Void Volume: 1.04 cu ft (0.0295 m3) per piece.
j.	Percentage of Concrete Displaced: 28.4 percent. 
k.	Weight Per Void: 5.1 lbs (2.31 kg).
F.	Basis of Design: CLS-V-8. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 45 psf (219.71 kg m2).
b.	Shear Factor: 0.44. 
c.	Stiffness Factor: 0.89. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 3.89 lbs sq ft (19.01 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.30 cf sq ft (9.10 cm).
b.	Support Void Height: 7.48 inch (190.0 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 12 inch (304.8 mm). 
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-4. 
f.	Half Shell Type: Bottom: CLS-H-4. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 1.20 cu ft (0.0340 m3) per piece.
j.	Percentage of Concrete Displaced: 30.0 percent. 
k.	Weight Per Void: 5.2 lbs (2.36 kg).
G.	Basis of Design: CLS-V-10.5. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 63 psf (307.59 kg m2). 
b.	Shear Factor: 0.41. 
c.	Stiffness Factor: 0.86. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 5.53 lbs sq ft (27.02 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.42 cf sq ft (12.80 cm).
b.	Support Void Height: 11.02 inch (279.9 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 16 inch (406.4 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-9. 
f.	Half Shell Type: Bottom: CLS-H-1.5. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2). 
i.	Void Volume: 1.68 cu ft (0.0476 m3) per piece.
j.	Percentage of Concrete Displaced: 32.5 percent. 
k.	Weight Per Void: 6.7 lbs (3.04 kg).
H.	Basis of Design: CLS-V-12. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 71 psf (346.65 kg m2).
b.	Shear Factor: 0.41. 
c.	Stiffness Factor: 0.86. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 6.14 lbs sq ft (29.99 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.47 cf sq ft (14.30 cm).
b.	Support Void Height: 12.20 inch (309.9 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 17 inch (431.8 mm). 
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-9. 
f.	Half Shell Type: Bottom: CLS-H-3. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 1.88 cu ft (0.0532 m3) per piece.
j.	Percentage of Concrete Displaced: 34.2 percent. 
k.	Weight Per Void: 7.1 lbs (3.22 kg).
I.	Basis of Design: CLS-V-12.5. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 74 psf (361.30 kg m2).
b.	Shear Factor: 0.40. 
c.	Stiffness Factor: 0.85. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 6.50 lbs sq ft (31.76 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.50 cf sq ft (15.20 cm).
b.	Support Void Height: 12.75 inch (323.9 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 18 inch (457.2 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-11. 
f.	Half Shell Type: Bottom: CLS-H-1.5. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 1.98 cu ft (0.056 m3) per piece.
j.	Percentage of Concrete Displaced: 33.9 percent.
k.	Weight Per Void: 7.4 lbs (3.36 kg).
J.	Basis of Design: CLS-V-13. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 77 psf (375.95 kg m2).
b.	Shear Factor: 0.40. 
c.	Stiffness Factor: 0.85. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 6.55 lbs sq ft (32.00 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.51 cf sq ft (15.50 cm).
b.	Support Void Height: 12.99 inch (329.9 mm). 
c.	Nominal Slab Thickness, No. 5 T and B: 18 inch (457.2 mm). 
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-9. 
f.	Half Shell Type: Bottom: CLS-H-4. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 2.04 cu ft (0.0578 m3) per piece.
j.	Percentage of Concrete Displaced: 35.0 percent. 
k.	Weight Per Void: 7.3 lbs (3.31 kg).
K.	Basis of Design: CLS-V-14. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 83 psf (405.27 kg m2).
b.	Shear Factor: 0.40. 
c.	Stiffness Factor: 0.84. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 7.17 lbs sq ft (35.05 kg m2). 
2.	Design Requirements: 
a.	Volume Displacement: 0.55 cf sq ft (16.80 cm).
b.	Support Void Height: 13.95 inch (354.3 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 19 inch (482.6 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-11. 
f.	Half Shell Type: Bottom: CLS-H-3. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 2.20 cu ft (0.0623 m3) per piece.
j.	Percentage of Concrete Displaced: 34.7 percent. 
k.	Weight Per Void: 7.8 lbs (3.54 kg).
L.	Basis of Design: CLS-V-15. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 89 psf (434.58 kg m2).
b.	Shear Factor: 0.40. 
c.	Stiffness Factor: 0.83. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 7.17 lbs sq ft (3505 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.59 cf sq ft (18.00 cm).
b.	Support Void Height: 14.74 inch (374.4 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 20 inch (508.0 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-11. 
f.	Half Shell Type: Bottom: CLS-H-4. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 2.36 cu ft (0.0668 m3) per piece.
j.	Percentage of Concrete Displaced: 35.4 percent.
k.	Weight Per Void: 8.0 lbs (3.63 kg).
M.	Basis of Design: CLS-V-18. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 108 psf (527.30 kg m2).
b.	Shear Factor: 0.40. 
c.	Stiffness Factor: 0.81. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 9.42 lbs sq ft (46.02 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.72 cf sq ft (22.00 cm).
b.	Support Void Height: 18.50 inch (469.9 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 24 inch (609.6 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-9. 
f.	Half Shell Type: Bottom: CLS-H-9. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2). 
i.	Void Volume: 2.88 cu ft (0.0816 m3).per piece.
j.	Percentage of Concrete Displaced: 36 percent. 
k.	Weight Per Void: 9.3 lbs (4.22 kg).
N.	Basis of Design: CLS-V-20. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 120 psf (585.89 kg m2).
b.	Shear Factor: 0.40. 
c.	Stiffness Factor: 0.80. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 10.44 lbs sq ft (51.01 kg m2).
2.	Design Requirements: 
a.	Volume Displacement: 0.80 cf sq ft (24.40 cm).
b.	Support Void Height: 20.25 inch (514.4 mm). 
c.	Nominal Slab Thickness, No. 5 T and B: 26 inch (660.4 mm).
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-11. 
f.	Half Shell Type: Bottom: CLS-H-9. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2).
i.	Void Volume: 3.20 cu ft (0.0906 m3) per piece.
j.	Percentage of Concrete Displaced: 36.9 percent. 
k.	Weight Per Void: 10 lbs (4.54 kg).
O.	Basis of Design: CLS-V-22. CLS Void, as supplied by Cobiax USA, Inc.
1.	Performance Requirements: 
a.	Associated Weight Reduction: 132 psf (644.47 kg m2).
b.	Shear Factor: 0.40. 
c.	Stiffness Factor: 0.80. 
d.	Concrete Minimum Specified Compressive Strength: 4,000 psi (27.58 MPa).
e.	Carbon Dioxide Emission Reduction: 10.65 lbs sq ft (52.05 kg m2). 
2.	Design Requirements: 
a.	Volume Displacement: 0.88 cf sq ft (26.80 cm).
b.	Support Void Height: 22.00 inch (558.8 mm).
c.	Nominal Slab Thickness, No. 5 T and B: 28 inch (711.2 mm). 
d.	Recommended Aggregate Range: 1/2 to 3/4 inch (12.7 to 19.1 mm).
e.	Half Shell Type: Top: CLS-H-11. 
f.	Half Shell Type: Bottom: CLS-H-11. 
g.	Void Plan Dimensions: 24 x 24 inch (609.6 x 609.6 mm).
h.	Area Per Void: 4.0 sf (0.37 m2). 
i.	Void Volume: 3.52 cu ft (0.0997 m3) per piece.
j.	Percentage of Concrete Displaced: 37.7 percent. 
k.	Weight Per Void: 10.7 lbs (4.85 kg).
P.	Materials: Top and Bottom Shell: Lightweight plastic void formers, 100 percent post-consumer, post-industrial, recycled polypropylene.
Q.	Fabrication: Injection molded. 
2.4	Fastenings: 
A.	Joint Reinforcement: Omega Hook: ASTM A615, Carbon Steel Rebar, Grade 60, No. 4, conventional. 
B.	Zip Ties: Supplied by Others: Concrete compatible polymer type recommended by void form distributor. 
C.	Tie wire, metal straps, and fastening devices supplied by Others. 
PART 3    EXECUTION
3.1	EXAMINATION
A.	Do not begin installation until formwork has been properly constructed and prepared. 
B.	If formwork preparation is the responsibility of another installer, notify Architect in writing of unsatisfactory preparation before proceeding.
C.	Verify dimensions, levels, and slopes conform to the Structural Drawings. 
D.	Verify application of form release agent, where required. 
E.	Verify installation of lower layer of reinforcement bars comply with Structural Drawings and ACI 318 requirements, and that reinforcement bar size, spacing, laps and bends are correct, and as indicated. 
3.2	PREPARATION
A.	Clean surfaces thoroughly prior to installation.
B.	Prepare surfaces using the methods recommended by the manufacturer for achieving the best result for the formwork under the project conditions.
C.	Sub-Base, Formwork Preparation: Ensure formwork of sub-base is clean, level, and free from debris, standing water, or any foreign material. 
3.3	INSTALLATION
A.	Assemble and install void formers in accordance with manufacturer's instructions, approved submittals, and in proper relationship with adjacent construction.
B.	Lay out and position void formers accurately, and in compliance with manufacturer's Placement Drawings. 
C.	Place void formers tightly together without gaps where indicated. 
D.	Ensure void formers are correctly oriented according to the product types, with smaller half-shells placed at the bottom of the assembly.
E.	Securing Void Formers:
1.	Secure void formers against uplift due to concrete buoyancy using specialized fixing elements. 
2.	Securing method must be sufficient to prevent any displacement or floating during concrete placement. 
3.	Ensure securing elements do not compromise integrity of void formers or surrounding concrete. 
F.	Install upper layer of reinforcement directly on top of void formers, were applicable and as indicated on the Structural Drawings. 
1.	Ensure proper concrete cover for upper reinforcement layers. 
2.	Integrate Omega bars within the x-zone as indicated on the Drawings to ensure shear transfer. 
a.	Place Omega bars vertically, unless otherwise indicated on the Structural Drawings, within solid concrete ribs formed around void formers. Install after void formers are set after final top layer of reinforcement to bridge the gap between upper and lower main reinforcement bars in quantity indicated on the Structural and Placement Drawings.
b.	Ensure Omega bars are properly placed on the bottom layer of the top mat and the bottom ends withing the concrete cross-section. 
G.	Single-Placement Concrete Installation: 
1.	Ensure adequate securing of void formers against buoyancy is used to prevent displacement. 
2.	Plan and execute single concrete placement method to prevent void former uplift and ensure proper consolidation of concrete around units in a single operation. 
3.	Place concrete in a single, continuous lift to final, specified slab thickness. 
4.	Use concrete with specified slump, mix design and strength, as indicated on the Structural Drawings and Specifications. 
5.	Place concrete carefully to avoid displacement or damage.
6.	Vibrate concrete thoroughly around and below void formers to ensure full encapsulation and eliminate honey-combing. Take care to avoid damaging void formers by over-vibration, or direct contact of vibrators with void formers. 
7.	Finish concrete surface according to Project specifications immediately following consolidation. 
H.	Double-Placement Concrete Installation: 
1.	First Concrete Layer in Voided Areas Only:
a.	Place first layer of concrete up to sufficient height to encapsulate and securely weigh down void formers, covering approximately 1 inch (25.4 mm) above the bottom of voids. 
b.	Use concrete with specified slump, mix design and strength, as indicated on the Structural Drawings and Specifications. 
c.	Ensure adequate securing of void formers against buoyancy is used to prevent displacement. 
d.	Vibrate first layer thoroughly around and below void formers to ensure full encapsulation and eliminate voids. Avoid damaging void formers by over-vibrating, or direct contact of vibrators with void formers. 
2.	Second Concrete Layer:
a.	Place second concrete layer after initial setting of first layer. 
b.	Immediately prior to placing second layer, verify surface of first layer is clean and free of contaminants or deleterious materials. 
c.	Depending on Project requirements and Engineering Specifications, saturated surface dry conditions with water or apply bonding agent. 
d.	Use concrete with the same specified slump, mix design, and strength as the first layer, unless otherwise indicated on the Structural Drawings. 
e.	Place second layer to final slab thickness. 
f.	Vibrate second layer to ensure proper consolidation without affecting first layer. 
g.	Finish concrete surface according to Project specifications immediately following consolidation. 
3.4	FIELD QUALITY CONTROL
A.	Field Inspection: Coordinate field inspection in accordance with appropriate sections in Division 01.
B.	Distributor's Services: Coordinate distributor's services in accordance with appropriate sections in Division 01.
C.	Distributor's representative will visit Project site prior to, or during initial placement of void formers before first placement of concrete. 
D.	Conduct pre-placement inspections to verify correct placement and securing void formers and Omega bars. 
E.	Monitor concrete slump, temperature and air content during placement. 
F.	Perform concrete strength tests, such as cylinder breaks, at specified intervals.
G.	Visually inspect consolidated concrete for honeycombing, voids or segregation atter stripping forms. 
H.	Maintain detailed records of all inspections, tests and any deviations or corrective actions taken. 

END OF SECTION