A Guide to Masonry Skills: Mixing and Using Cement | North Salem NY Real Estate

The world’s strongest foundations, footings and masonry walls are made with concrete or mortar—mud as it’s called here in MOTHER’s neck of the woods. But many newcomers to country life shy away from working the stuff, perhaps because the chemistry of it seems alien to the more natural lifestyle they’re seeking.

It isn’t, really. The cement that is the heart of all mudwork comes from good and natural things like limestone, oyster shells and iron ore, which are fused in a kiln, then ground from hard clinkers into a fine powder. Mixed with varying amounts of sand, gravel or crushed stone aggregate, this forms the dry base for concrete, the plastic mix that hardens into bridges and garden walks, or—with the addition of lime—mortar that’s used to bond brick, stone and precast concrete blocks.

When water is added to the dry base, it combines chemically with the cement in a process called hydration. The resulting paste solidifies within the hour, binding in the aggregates for now and always. Over a period of three days it cures and hardens to nearly half its finished strength, and in a month or more returns to rock.

A Trial Cement Mix 

The best way to learn about any skill is to do it, and working mud is no exception. Buy an 80-pound bag of packaged concrete mix, and with it get a 9 inch or 10 inch brick or pointing trowel (Figure 1), a hoe and a pair of leather work gloves. For what it’s worth, a real mortar hoe has a pair of holes in the blade to make mixing easier; my old garden hoe has no holes, but carries a rind of dry cement on the shaft anyway. As for the gloves, masons rarely use them, but wet concrete and mortar are somewhat caustic and can dry the skin and burn the eyes. Cement also makes a great bleaching agent, so don’t work mud wearing your best jeans.

Professionals always make a trial mix of any new combination of materials to determine the best proportions for the job at hand; so do I, and so should you. To see what mud should and shouldn’t look like, clean out a steel barrow or make up a mortar box (Figure 2); or use an old 4 foot by 8 foot sheet of plywood to serve as an even simpler mortar-mixing board. Mound the dry mix, and scrape out a dent in the center to make a doughnut shape. Add water, and use your hoe to push the inner edge of the doughnut out away from the puddle and then to pull dry mix from the outer perimeter back and into the water. Don’t let the round dam of mix break, or all your liquid and much of the cement will flow off from the gravel and sand.