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CMU concrete block contractor masonry tips

How to Choose the Right CMU Block for Your New England Project

By NE Build Supply Team ·April 29, 2026

Whether you're a seasoned masonry contractor or managing your first commercial build, selecting the right concrete masonry unit (CMU) can make the difference between a structure that stands for decades and one that needs costly repairs within a few years. Here's what our team at New England Building Supply recommends every contractor know before placing an order.

1. Match the Block to the Application

Not all CMUs are created equal. Standard 8x8x16 blocks work well for most above-grade walls, but below-grade and retaining applications call for dense aggregate blocks with higher compressive strength. Load-bearing walls need blocks rated to at least 1,900 PSI — always verify your engineering specs before ordering.

2. Consider the New England Climate

Freeze-thaw cycles are a real concern in our region. Blocks used in exterior applications should meet ASTM C90 Grade N standards for weather resistance. Low-absorption blocks (under 8% by weight) perform significantly better through harsh winters.

3. Plan Your Mortar Joint Accordingly

Face shell bedding is standard for most applications, but full mortar bedding is required for columns and piers under heavy load. We carry a full range of mortar types and can advise on the right mix for your specific project conditions.

4. Don't Overlook Lead Time

Standard gray block is typically available same-week, but specialty sizes, split-face finishes, or architectural block may require 2-3 weeks. For large commercial projects, confirm availability 4-6 weeks ahead of your pour date.

5. Think About Delivery Logistics

A typical pallet holds 90 standard 8x8x16 blocks. Most sites need a boom truck or forklift on site. For tight urban sites, we can arrange staged deliveries to keep work flowing without disruption. Contact our team to discuss your next project.

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