Replace the YouTube link above with your Division 04 study video.

• Check whether the project uses standard or split-face CMU — it affects material and cost.
• Mortar type (S, N, M) is crucial to structural integrity — verify in specs.
• Wall reinforcement and joint reinforcements are often missed in takeoffs.
• Flashing and weep holes are typically detailed under Division 07 but referenced here.
• Understand tolerance limits for coursing and joint alignment — inspectors do!

1. What’s the difference between standard and split-face CMU?
   Answer: Split-face CMU has a rough, textured surface for visual walls and costs more than standard block.
2. Why does mortar type (S, N, M) matter?
   Answer: It affects compressive strength and bonding — the wrong type can lead to wall failure.
3. What reinforcement is typically called out for masonry walls?
   Answer: Horizontal joint reinforcement and vertical rebar in grouted cells.
4. Where are flashing and weep holes typically detailed?
   Answer: Usually under Division 07 but must be referenced in Division 04 to coordinate layout.
5. What should you know about coursing and joint tolerances?
   Answer: Specs define how much deviation is allowed in alignment — inspectors use this to approve or reject work.

Division 04: Masonry

🔹 Key Teaching Points

1️⃣ Know Your CMU Type

• Check if the project uses standard or split-face CMU — it affects cost and aesthetics.
• Split-face is often used for exterior visual walls and costs more.

2️⃣ Mortar Type Affects Strength

• Mortar types S, N, and M serve different purposes based on compressive strength.
• Verify the correct type in the spec to meet structural needs.

3️⃣ Don’t Skip Reinforcement

• Horizontal joint reinforcement and wall rebar are critical to wall performance.
• Often missed in estimating — confirm with structural drawings and specs.

4️⃣ Flashing and Weep Holes are Critical

• Division 07 often covers waterproofing, but Division 04 should reference weeps and flashing details.
• These are key to long-term durability and water resistance.

5️⃣ Know Your Tolerances

• Specs usually state allowable deviations for coursing and alignment.
• Inspectors will measure joint consistency — don't leave it to chance.

✅ Wrap-Up Summary

• Masonry specs affect appearance, structure, and waterproofing.
• Take time to review material type, installation method, and QC measures.
• Missing a single weep hole or bar can lead to failure or failed inspection.