Worth it for contractors who need structural-grade mortar that handles Montana’s freeze-thaw abuse. The 1800 psi compressive strength at 28 days and ASTM C270 compliance make it suitable for load-bearing walls above and below grade. Each 80 lb bag yields approximately 37 standard bricks or 13 standard 8x8x16 concrete blocks.
Skip it if you’re just pointing up a chimney or laying veneer stone. Type N mortar costs less and works fine for non-structural applications above grade.
Yield and Coverage Math That Actually Matters
Each bag lays 37 standard bricks or 13 standard 8x8x16 CMU blocks. Those numbers assume a standard 3/8-inch mortar joint and typical waste. Real-world coverage depends on your mason’s technique and the actual size of your units.
Water demand runs approximately 5 quarts per bag, with a maximum of 7 quarts. Start with 5 quarts. The mix should be stiff enough to support the weight of masonry units without sagging but workable enough to achieve full bed coverage. Too much water weakens the mortar and increases shrinkage cracking.
For estimating purposes on a typical block foundation:
- 100 blocks = 8 bags (rounded up from 7.7)
- 500 blocks = 39 bags
- 1000 blocks = 77 bags
Always order 10% extra. Between dropped blocks, contaminated batches, and the inevitable need for three more courses, there’s always more usage than calculated.
Type S Classification and Montana Applications
Type S mortar delivers a minimum 1800 psi compressive strength at 28 days. That strength rating puts it between Type N (750 psi) and Type M (2500 psi), making it the go-to choice for structural masonry that needs more muscle than Type N but doesn’t require the overkill of Type M.
| Mortar Type | Compressive Strength | Montana Applications |
|---|---|---|
| Type S (This Product) | 1800 psi | Structural, load-bearing, below-grade |
| Type N | 750 psi | Non-structural, above-grade only |
| Type M | 2500 psi | Highest strength, retaining walls, heavy loads |
Below-grade capability matters in Montana where frost lines run 36-48 inches deep. The product includes “foundation walls” and “below-grade use” in its applications list. Type S handles the lateral pressure from backfill and the freeze-thaw cycling that destroys weaker mortars.
Compliance with ASTM C270 and C1714 means it meets industry standards for both traditional field-mixed mortar (C270) and pre-blended mortar (C1714). Not every bagged mortar meets both standards.
Pre-blended Convenience vs Old-School Site Mixing
This pre-blended mixture of masonry sand and Type S cement requires no on-site sand or lime addition. That’s the entire point. No sand pile. No lime bags. No guessing proportions. No weather-damaged materials.
The labor math favors pre-blended every time:
- Site-mixed: Source sand, store it dry, measure proportions, hope your laborer doesn’t mess up the recipe
- Pre-blended: Open bag, add water, mix minimum 5 minutes, start laying
Consistent mix and workability beats site-mixed mortar where every batch depends on whoever’s running the mixer that day. When mason labor time matters, wasting time on material prep doesn’t make sense.
Pre-blended costs more per bag than buying cement and sand separately. But factor in delivery charges for bulk sand, storage requirements, weather protection, and labor time — pre-blended usually wins on total cost for anything under 1000 blocks.
Installation and Mixing
Surface must be clean, dry, and free of loose material before starting. Add approximately 5 quarts of clean water to the container, then add mix and blend for 5 minutes. Don’t dump the powder first — you’ll get unmixed pockets at the bottom.
Apply 1/2 to 3/4 inch mortar bed, then press units into place and twist slightly. That twist motion ensures full contact between mortar and masonry unit. Tool joints when thumb-print hard for a smooth, watertight finish.
Mist with water in hot or dry conditions to prevent rapid moisture loss. Montana’s low humidity and high elevation can suck moisture out of fresh mortar faster than you’d expect, especially in summer. Keep a spray bottle handy.
The product is compatible with QUIKRETE Liquid Cement Color (No. 1317) for colored mortar joints. Most contractors stick with natural gray, but colored mortar can hide repairs or match existing work.
The Contractor’s Verdict
At 4.3 stars average rating across retailers with review counts showing 690 at Master Wholesale and 1,265 at Home Depot, it’s regarded as highly rated for strength and consistency and an industry standard for structural masonry.
Type S hits the sweet spot for Montana masonry work. Strong enough for structural applications and below-grade placement, but not so strong it becomes brittle like Type M. The pre-blended consistency saves labor time and eliminates mix variations between batches.
The 80-pound bags aren’t fun to handle, but they’re the industry standard. Store them dry — even with “weather-resistant” packaging, moisture will eventually find its way in and you’ll have 80-pound rocks instead of mortar.
For foundation walls, structural columns, and any masonry going below grade in Montana’s freeze-thaw climate, Quikrete Type S delivers the strength and durability the job demands. Just remember: this is structural mortar. Don’t waste it on decorative work where Type N would do the job for less money.
Frequently Asked Questions
Q: How many bricks or blocks will one 80 lb bag of Quikrete Type S Mortar cover?
One 80 lb bag yields approximately 37 standard bricks or 13 standard 8x8x16 concrete blocks (CMU). These coverage numbers assume a standard 3/8-inch mortar joint and typical waste factors.
Q: What’s the difference between Type S and Type N mortar?
Quikrete Type S delivers 1800 psi compressive strength at 28 days and is suitable for structural, load-bearing, and below-grade applications. Type N mortar only provides 750 psi strength and is limited to non-structural, above-grade use only.
Q: How much water should be added per bag of Quikrete Type S?
Mix approximately 5 quarts (4.7 L) of clean water per 80 lb bag, with a maximum of 7 quarts (6.6 L). Start with 5 quarts and adjust for workability — too much water weakens the mortar and increases shrinkage cracking.
Q: Is Quikrete Type S suitable for foundation walls below grade?
Yes, Quikrete Type S is specifically designed for below-grade applications including foundation walls and structural columns. Its 1800 psi strength and ASTM C270 compliance make it suitable for masonry that needs to handle lateral pressure from backfill and freeze-thaw cycling.
Q: Does Quikrete Type S require adding sand or lime?
No, this is a pre-blended mixture of masonry sand and Type S cement that requires no on-site sand or lime addition. Just add water, mix for a minimum of 5 minutes, and it’s ready to use.
Q: What kind of masonry units work with Quikrete Type S?
Quikrete Type S is compatible with brick, CMU blocks, and natural stone for laying, tuck-pointing, and repair work. The mortar meets both ASTM C270 and C1714 standards for structural masonry applications.
Ready to Get Started?
Our building materials specialists can help you find the right Quikrete products for your project.
More from Quikrete
Explore All Quikrete Products
We carry Quikrete across all 11 Montana and Idaho stores.
