See Tables 1 and 2 for visually graded lumber species and lumber species combinations and assigned specific gravity per the National Design Specification (NDS) for Wood Construction. Assigned specific gravity in the NDS is an average property based on weight and volume when oven-dry. Bold entries are commonly available lumber species combinations used in International…
A list of lumber grading rules writing organizations certified by the American Lumber Standards Committee (ALSC) is provided below. NELMA. Standard Grading Rules for Northeastern Lumber; published by the Northeast Lumber Manufacturers Association (NELMA), 272 Tuttle Road, P.O. Box 87A, Cumberland Center, ME 04021; 207.829.6901; 207.829.4293 (fax); e-mail [email protected] RIS. Standard Specifications for Grades of…
With few exceptions, lumber species or lumber species combination (usually in abbreviated form) is a standard component of lumber grade stamps per the American Lumber Softwood Lumber Standard – PS20. These grade mark components are illustrated below for Visually Graded Lumber. An example grade stamp for S-P-F (or Spruce-Pine-Fir) lumber species combination is shown below: …
Where can I obtain information on designing post frame structures (sometimes referred to as pole buildings or pole barns)? 1. Design values for poles (smaller at the top and buried) and piles (smaller at the bottom and driven) are in the 2005 NDS Chapter 6. Design values for poles and piles were moved to the NDS Supplement: Design Values…
The Southern Forest Products Association (SFPA) publishes the Permanent Wood Foundations Design and Construction Guide. Download the document here. AWC’s PWF Design Fabrication Installation (DFI) Manual and Technical Report #7, Permanent Wood Foundation System Basic Requirements (TR7) have both been discontinued and are out of print. ANSI / AWC PWF – Permanent Wood Foundation Design Specification replaces TR7 and has been adopted in the 2009/2012 International…
Designing Retaining Walls, Bulkheads and Seawalls of Treated Timber. Author: American Wood Preservers Institute, 1966 Earth Retaining Structures. Author: W.D. Keeney, AWPI Improved Standard Designs Pressure-Treated Timber Crib Walls. AWPI, 1969. Available upon e-mail request: [email protected].
Guidance for this issue can be found in the commentary to the Permanent Wood Foundation Design Specification. The PWF commentary states in C5.4.5: Since nominal unit shear capacities for shear walls and diaphragms published in the Special Design Provisions for Wind and Seismic (SDPWS) Specification are based on short-term load duration, it is necessary to multiply…
Anchor bolt connections designed per SDPWS 4.3.6.4.3 are designed for the shear load in the sill plate. If the shear capacity of a double-sided shear wall is twice that of a single-sided shear wall, the anchor bolt spacing derived based on the anchor bolt shear capacity for a double-sided shear wall would be half the spacing of…
The National Design Specification® (NDS®) Supplement tables list design values for 2x and larger decking. The American Lumber Standards Committee (ALSC) provides a Policy for Evaluation of Recommended Spans for Span Rated Decking Products. Here’s more information on their website: https://alsc.org/lumber-recommended-spans-for-decking/ You will need to contact the specific grading agencies to obtain their span ratings for various species. A…
AWC’s Special Design Provisions for Wind and Seismic, Table 4.2D contains shear capacities for lumber sheathing attached straight and diagonally. Table 4.3D contains shear wall capacities for straight and diagonal lumber sheathing as well. AWC also publishes Plank and Beam Framing for Residential Buildings (WCD-4) (T14). It shows how this floor and roof framing system, traditionally used in…