When a steel column base plate or a machine anchor has to sit dead level and stay there under load, ordinary sand mix simply will not do the job. Quikrete non shrink grout is a precision, cement-based product engineered to flow into tight gaps and cure without the shrinkage that leaves conventional grout cracked and hollow underneath. It is a structural material, not a tile grout, and confusing the two is the most common mistake homeowners make. This guide covers exactly where it belongs, how to mix it to the right consistency, and how to place it so it performs the way the spec sheet promises.
What Non Shrink Grout Actually Is
Despite the shared brand name, this product has nothing to do with the colored grout you push between ceramic tiles. Quikrete Non-Shrink Precision Grout (product No. 1585) is a blend of Portland cement, graded sand, and additives that compensate for the natural volume loss of curing concrete. Where a standard mix pulls away from the edges of a pour, non-shrink grout holds its dimension or expands slightly, so it maintains full contact and transfers load evenly.
That property is why engineers specify it for load-bearing applications. It typically reaches around 5,000 psi compressive strength at 7 days and can exceed 8,000 psi at 28 days, far beyond what a general-purpose concrete mix delivers.
Where to Use It
The right applications share a common theme: a precise, load-carrying gap that must be filled completely. Common uses include:
- Setting steel column base plates and leveling structural steel
- Grouting anchor bolts and dowels into cored or drilled holes
- Bedding machine bases and equipment that must resist vibration
- Filling gaps beneath precast panels and bearing plates
- Structural repairs and patching where high early strength matters
It is not the product for a tile floor, a shower pan, or a decorative joint. For those, you want a sanded or unsanded tile grout instead. Using structural grout on tile leaves you with a surface that is nearly impossible to tool cleanly and far too hard to remove later.
Consistency Options: Plastic, Flowable, and Fluid
One of the strengths of this grout is that a single bag mixes to three working consistencies simply by changing the water. Choose based on how the grout has to travel.
Plastic (Dry-Pack)
Using the least water gives you a stiff, packable mix ideal for dry-packing under a base plate by hand and rodding it into place. This consistency holds its shape and is used where you cannot form a dam for pouring.
Flowable
A medium water dose produces a pourable grout that self-consolidates into moderate gaps. This is the most common choice for base plate grouting where you can build a form on three sides.
Fluid
The maximum recommended water yields a fluid grout that flows into tight clearances and around congested anchor bolts. Never exceed the manufacturer’s stated water limit chasing more flow; over-watering slashes strength and can reintroduce shrinkage.
How to Mix Quikrete Non Shrink Grout
Accurate mixing separates a durable pour from a weak one. Work in a clean mortar tub or use a paddle mixer on a low-speed drill for anything more than a partial bag.
- Start with roughly 80 to 90 percent of your target water in the tub.
- Add the dry grout gradually while mixing to avoid dry pockets and lumps.
- Blend for 3 to 5 minutes until uniform, then add the remaining water in small amounts to dial in the consistency you need.
- Mix only what you can place in about 15 minutes; working time is short and shrinks further in hot weather.
A 50-pound bag yields approximately 0.45 cubic feet of grout, so calculate your gap volume first and mix full bags rather than eyeballing partial batches, which makes consistent water ratios difficult.
Placement and Curing
Preparation of the surface matters as much as the mix. The concrete beneath should be clean, sound, and pre-wetted to a saturated surface-dry condition so it does not pull water out of the fresh grout. For base plates, build a tight form on the sides you are not pouring from, and place from one side only so the grout pushes air ahead of it and fills the entire cavity without voids.
Once placed, protect the grout from rapid drying. Cover it with wet burlap or plastic and keep it damp for at least three days, or apply a curing compound. Skipping this step in direct sun or wind causes surface cracking and undercuts the very shrinkage control you paid for. Do not place structural grout when temperatures are below 40°F unless you take cold-weather precautions, and keep it out of the hottest part of the day when possible.
Non Shrink Grout vs. Standard Concrete Mix
Homeowners often ask why they cannot just use a bag of sand mix or general-purpose concrete for a base plate, and the answer comes down to what happens as the material cures. Standard concrete and mortar shrink as they lose water, pulling away from the edges of a pour and leaving voids beneath a plate. Under load, those voids concentrate stress and can crack the bearing surface or let a machine base rock and vibrate loose.
Non-shrink grout is engineered to hold its volume, so it stays in full contact with both the concrete below and the steel above. It also develops far higher early strength, reaching roughly 5,000 psi in a week where a general mix might need a month to approach that figure. For anything decorative or non-structural, standard concrete is fine and cheaper. But the moment a connection has to carry load and stay level, the precision grout earns its higher price several times over.
Common Application Mistakes
A few repeat errors undermine otherwise sound pours. Watch for these:
- Over-watering the mix to make it flow better, which slashes strength and reinvites the shrinkage you are paying to avoid.
- Pouring from two sides at once, which traps air in the middle and leaves voids under the plate.
- Failing to pre-wet the concrete, so the dry slab pulls water out of the grout and weakens the bond.
- Skipping the wet cure, which lets the surface dry too fast and crack in the sun or wind.
- Mixing more than you can place in the short 15-minute working window, leaving you with stiff, unusable material.
Avoiding these keeps the grout performing exactly the way the engineer specified, and it takes only a little planning rather than any extra material.
Coverage, Cost, and Safety
Budgeting is straightforward once you know your gap volume. A 50-pound bag runs roughly $18 to $30 at most home centers and covers about 0.45 cubic feet, so a base plate with a 1-inch grout bed under a 2-foot-square plate needs only a fraction of a bag. Buy at least one extra bag for congested anchor pours where waste is unavoidable.
Wear waterproof gloves and eye protection; wet cement is caustic and can burn skin on prolonged contact. Mix in a ventilated area and avoid inhaling the dry silica dust, and rinse any skin contact promptly with plenty of water.
Store unopened bags off the ground and out of humidity, since even a small amount of absorbed moisture can cause premature setting and clumping that ruins the grout before you ever open it. Check the date on the bag and use older stock first. Used correctly, Quikrete non shrink grout gives you a rock-solid, full-contact bearing surface that keeps steel and equipment level for the life of the structure, which is exactly the reliability a critical load connection demands. For a modest material cost and a little care in mixing and curing, it delivers structural performance that no general-purpose concrete can match.
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