SECTION 06 13 00

HEAVY TIMBER CONSTRUCTION

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PART 1    GENERAL
1.1	SECTION INCLUDES
A.	Structural design, fabrication, and installation of the following:
1.	Heavy Timber Beams, Columns, and Trusses
2.	Pegs
3.	Heavy Timber Connections
4.	Miscellaneous Hardware
1.2	RELATED SECTIONS
A.	Section 06 10 00 - Rough Carpentry.
1.3	REFERENCES
A.	American Welding Society (AWS):
1.	Code for Arc and Gas Welding in Building Construction.
B.	American Wood Protection Association (AWPA):
1.	Standard M4 - Standard for the Care of Preservative-Treated Wood Products.
2.	Use Category System.
C.	ASTM International (ASTM):
1.	ASTM A36 - Standard Specification for Carbon Structural Steel.
2.	ASTM A53 - Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless.
3.	ASTM A123 - Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products.
4.	ASTM A153 - Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware.
5.	ASTM A575 - Standard Specification for Steel Bars, Carbon, Merchant Quality, M-Grades.
6.	ASTM A1011 - Standard Specification for Steel, Sheet and Strip, Hot-Rolled, Carbon, Structural, High-Strength Low-Alloy, High-Strength Low-Alloy with Improved Formability, and Ultra-High Strength.
D.	Western Wood Products Association (WWPA):
1.	Western Lumber Grading Rules.
1.4	DEFINITIONS
A.	FOHC: Free of Heart Center.
B.	S4S: Surfaced Four Sides.
1.5	SUBMITTALS
A.	Submit under provisions of Section 01 33 00 - Submittal Procedures.
B.	Product Data:
1.	Manufacturer's data sheets on each product to be used including preservative-treated wood products and timber connectors.
2.	Preparation instructions and recommendations.
3.	Storage and handling requirements and recommendations.
4.	Typical installation methods.
C.	Verification Samples: Submit two representative samples not less than 4x12x1 inch(es) of wood species indicated showing the range of variation in appearance, surface texture, and expected color range.
D.	Shop Drawings: Include details of all materials, construction, and finish. Include relationships with adjacent construction. Provide the following:
1.	Small scale plans and elevations showing all truss members, joints and methods of assembly. Include exploded representation drawings for assemblies.
2.	Shop Drawings shall include stress analysis and joint design by a practicing registered professional engineer with structural engineering credentials, licensed to practice in the state of (fill in state). The Shop Drawings shall bear the seal of the registered professional engineer.
3.	Truss design shall provide the required stability and resistance to gravity loads.
4.	No trusses shall be ordered or fabricated prior to the approval of the Shop Drawings by the Architect.
E.	Delegated Design Submittals:
1.	For heavy timber members and assemblies, include shop drawings, analysis and structural design signed and sealed by a qualified professional engineer responsible for their preparation..
F.	Certificates of Inspection: Issued by approved lumber grading agency for exposed timber without grade stamp.
1.6	QUALITY ASSURANCE
A.	Manufacturer Qualifications: Company specializing in manufacturing products specified in this section with a minimum of five years documented experience.
B.	Installer Qualifications: Company specializing in performing Work of this section with minimum two years documented experience with projects of similar scope and complexity.
C.	Source Limitations: Provide each type of product from a single manufacturing source to ensure uniformity.
1.7	PRE-INSTALLATION CONFERENCE
A.	Convene a conference approximately two weeks before scheduled commencement of the Work. Attendees shall include Architect, Contractor, and trades involved. Agenda shall include schedule, responsibilities, critical path items, and approvals.
1.8	DELIVERY, STORAGE, AND HANDLING
A.	Protect trusses and keep under cover in transit and at the job site. Stack to ensure proper ventilation and drainage. Store under cover in a well-ventilated area. Trusses damaged in shipment or at the job site shall be repaired or replaced at no cost to the Owner.
B.	Protect from damage due to weather, excessive temperature, and construction operations.
1.9	PROJECT CONDITIONS
A.	Maintain environmental conditions (temperature, humidity, and ventilation) within limits recommended by manufacturer for optimum results. Do not install products under environmental conditions outside manufacturer's recommended limits.
1.10	WARRANTY
A.	Manufacturer's standard limited warranty unless indicated otherwise.
PART 2    PRODUCTS
2.1	MANUFACTURERS
A.	Acceptable Manufacturer: Vermont Timber Works, Inc., which is located at:<BR />16 Fairbanks Rd.<BR />North Springfield, VT 05150<BR />Tel: 802-886-1917<BR />Fax: 802-886-6188<BR />Email: request info (sales@vermonttimberworks.com);Web: https://www.vermonttimberworks.com 
B.	Substitutions: Not permitted.
2.2	TIMBER
A.	Provide grade compliance certificates in lieu of grade stamps where stamps would be exposed to view or removed during production.
B.	Timber Species and Grade:
1.	Douglas fir, select structural, rough sawn or S4S, FOHC.
2.	Douglas fir, #1 and better, rough sawn or S4S, FOHC.
3.	Douglas fir, #1 and better, rough sawn or S4S
4.	Port Orford Cedar #1 & better.
5.	White, red or mixed oak #2 & better. 
6.	Native hemlock, rough sawn or S4S.
7.	Native white pine, rough sawn or S4S.
C.	Moisture Content: 19 percent maximum at time of fabrication.
2.3	PRESERVATIVE-TREATED WOOD MATERIAL
A.	Cut, drill, surface, and sand members before treatment. When not possible, apply a field-applied preservative treatment in compliance with AWPA M4.
B.	Klear-gard or approved equal. Use a water repellant treatment process.
2.4	HEAVY TIMBER BEAMS, COLUMNS, AND TRUSSES
A.	Timber shall be sized according to engineering requirements. Minimum member sizes as follows:
1.	Joists and Rafters: 4 inches nominal, S4S.
2.	Knee Braces: 4x6 inches nominal, S4S.
3.	Timbers: 6 inches nominal, S4S.
B.	Unless otherwise noted, all timber shall be per "Western Lumber Grading Rules" by the Western Wood Products Association. Records of grade marks and certificates indicating conformance with the Specifications shall be maintained by the Contractor.
C.	Edge Details: As indicated on Drawings. Wane requirements as follows:
1.	Douglas Fir: Pencil wane is acceptable.
2.	Native Species: 1-1/4 inches maximum.
D.	Finish: Pre-finish all surfaces and joints with one coat of Vermont Natural Coatings, or equal.
2.5	PEGS
A.	Peg Materials: Use straight grained, all heartwood, knot free, and reaction free from birch or oak.
2.6	HEAVY TIMBER CONNECTIONS
A.	Traditional Joinery or metal timber connections can be used as required by the structural and aesthetic design. When traditional joinery is used, metal connections must be concealed and held at an absolute minimum, meeting the Architect's approval.
B.	Steel Timber Connectors: 
1.	Materials: Unless otherwise indicated, use the following:
a.	Hot-rolled Steel Sheet: ASTM A1011, Structural Steel, Type SS, Grade 33.
b.	Round Steel Bars: ASTM A575, Grade M 1020.
c.	Structural Steel Shapes, Plates, and Flat Bars: ASTM A36.
2.	Finishes:
a.	Steel components: Rust-inhibiting primer finish, 2 mil minimum dry film thickness.
b.	Steel components: Hot-dipped galvanized finish after fabrication complying with ASTM A123 or ASTM A153. 
3.	Design: As indicated on Structural Drawings.
C.	Workmanship: High quality as indicated in the Drawings or Shop Drawings and subject to the Architect's review and approval.
2.7	MISCELLANEOUS HARDWARE
A.	Furnish and install all necessary hardware and metal shapes required for assembly and erection of the trusses.
B.	All steel shapes, plates, and tubes, unless otherwise specified, shall conform to ASTM A36, as amended to date. Steel pipe shall conform to ASTM A53, Grade B.
C.	Where welding is called for, it shall be by the electric arc process in accordance with the American Welding Society's Code for Arc and Gas Welding in Building Construction.
D.	All other steel shapes, plates, tubes, etc. shall be thoroughly cleaned and given one heavy shop coat of an approved red lead primer (black), well worked into all joints and open spaces. After erection, touch-up as required. Surfaces which are not accessible for field painting shall have one shop coat of black paint before leaving the shop.
E.	Bolts shall be zinc/galvanized with zinc/galvanized washers and nuts.
2.8	FABRICATION
A.	Shop Fabrication: Cut and finish exposed surfaces to match specified surfacing. Finish exposed surfaces to remove surface marks and provide a finish equivalent to machine sanding with No. 100 grit sandpaper.
B.	Seal Coat: Provide a water based factory penetrating sealer on all surfaces of heavy timber products after fabrication. Exclude preservative-treated wood materials which include a water repellent.
C.	Coat crosscuts with end sealer.
PART 3    EXECUTION
3.1	EXAMINATION
A.	Do not begin installation until the substrates have been properly constructed and prepared.
B.	If substrate preparation is the responsibility of another installer, notify Architect in writing of unsatisfactory preparation before proceeding.
3.2	PREPARATION
A.	Provide sufficient clear working space for materials, labor, and equipment prior to the start of work.
B.	Prepare surfaces using the methods recommended by the manufacturer for achieving the best result for the substrate under the project conditions.
3.3	MEASUREMENTS
A.	General Contractor to obtain and verify all measurements and conditions at building as required for the proper installation of the work. Heavy timber contractor to be responsible for accuracy and fit of various parts of their work and proper building-in of same according measurements provided in the project drawings and field measurements.
3.4	INSTALLATION
A.	Installation of trusses shall be in accordance with the details and notes on the Drawings, the approved Shop Drawings, code requirements, and the best trade practices.
B.	Install heavy timber framing members true and plumb.
C.	Provide temporary bracing until permanent elements are installed.
3.5	JOINERY
A.	Joinery shall be in the best of the early English and early American traditions, designed for strength, shrinkage, checking, and twisting.
B.	All joinery shall be accurately cut so as to make a neat, snug fit.
C.	Pre-drill fastener holes in the factory to the greatest extent possible.
3.6	ERECTION
A.	Truss components and assemblies must be checked for dimensions and anchorage accuracy before erection.
B.	Temporary bracing and guy lines shall be provided to adequately protect all persons and property and to insure proper alignment.
C.	Padding or non-marking slings shall be used, and corners shall be protected with blocking.
D.	The assembled trusses shall be reasonably straight, plumb, level and square. Portions of the structure not adequately braced by design shall have temporary braces until the decking is applied.
E.	All joints shall be reasonably tight.
F.	All joints that require pegging shall have pegs driven until snug or flush. Pegs shall protrude 1 to 2 inches on both sides of truss except where they should be flush as directed above. Broken pegs shall be removed and replaced. Pegs with a mushroomed head shall be cut off below that portion
G.	Tools used to drive or pull joints together shall not permanently mar the finished surfaces of the trusses.
3.7	FIELD QUALITY CONTROL
A.	Field Inspection: Coordinate field inspection in accordance with appropriate sections in Division 01.
B.	Manufacturer's Services: Coordinate manufacturer's services in accordance with appropriate sections in Division 01.
3.8	CLEANING AND PROTECTION
A.	Clean products in accordance with the manufacturers recommendations. 
B.	Touch-up, repair or replace damaged products before Substantial Completion to the satisfaction of the Architect.

END OF SECTION