High School

The use of bridging is only required by code when joists are deeper than what dimension?

A. 2x6
B. 2x8
C. 2x10
D. 2x12

Answer :

Sure! When you're dealing with construction and building codes, one important aspect to consider for floor joists is whether you need to use bridging. Bridging helps to prevent joists from twisting, which improves stability and support.

According to the most common building codes, bridging is required when the depth of the joists exceeds a certain size. Here's a step-by-step explanation:

1. Understand the Options: You have the following joist dimensions to choose from:
- 2x6
- 2x8
- 2x10
- 2x12

2. Identify the Depths: Let's assign approximate depth values:
- A 2x6 joist is about 5.5 inches deep.
- A 2x8 joist is about 7.25 inches deep.
- A 2x10 joist is about 9.25 inches deep.
- A 2x12 joist is about 11.25 inches deep.

3. Determine Bridging Requirement: The building code typically requires that bridging is used for joists deeper than 2x10. This is because deeper joists are more likely to twist or deflect, so they need the additional support provided by bridging.

4. Final Decision: Since we're looking for the depth beyond which bridging is required, joists deeper than 2x10 need bridging.

Therefore, bridging is only required by code when joists are deeper than 2x10.