Connections Tutorial 3 – Screw Lap Splice (Canadian)

Connections Tutorial 3 – Screw Lap Splice (Canadian) 3.1 Introduction This tutorial goes over the design of a screw lap splice connection between OSB and a solid sawn member. The problem is the same as example 1 on page 256 of the 2015 edition of the Canadian Wood Council Wood Design Manual. See explanation on page 257 of the WDM. Due to the lack of screw penetration into the third member in the splice, the problem must be considered as a single shear connection. Click here to download the connections file (.des) which will be created by going through this tutorial.

3.2 Connection Type 1. Click the New button on the toolbar. 2. Select the connection type Lapped Shear, wood-to-wood, Splice two-member. 3. Select Wood Screws.

Connections Tutorial 3 – Selecting Screw Splice Connection

3.3 Connection Details Main Member 1. 2. 3. 4. 5.

Specify Material to Lumber joist. Specify Species as S-P-F. Specify Grade as No.1/No.2. Specify Thickness as 38 mm. Specify Width as 140 mm.

Connections Tutorial 3 – Main Member Details

Side Member 1. 2. 3. 4. 5. 6.

Specify Material to OSB. Specify Species as all. Specify Thickness as 11 mm. Specify Width as 140 mm. Specify End Type as Unknown. Specify a Force of 8 kN.

Connections Tutorial 3 – Side Member Details

Screw Details 1. 2. 3. 4.

Specify a Screw Gauge Number of 6. Specify a Wood Screw Length of 1-3/4. Select the box Add Staggered Screws Between Rows. Click Run Design.

Connections Tutorial 3 – Screw Details

3.4 Review and Accept Design Results Once the design has been run, it is possible to review the Diagram, Results and Accept the design. For this example, 18 1-¾ inch screws were found to be adequate in resisting the specified load. Both the Diagram and Results can quickly be printed using the Print icon. Click here download a pdf of the diagram. Click here to download a pdf of the results.

Connections Tutorial 3 – Screw Splice Results