Casting a Patio

THE PATIO SLAB should be an integral part of the over-all plan for house and grounds. Many things affect decisions con­cerning size, shape and placement. How important is privacy? (Do you occasionally want to use the patio for sunbathing?) How about prevailing winds? A breeze constantly blowing across your favorite outdoor lounging chair can be very annoying. How about your gardening interests? Do you want a picture-book effect with bor­ders of colorful annuals, or do you want to spend more time just sitting? (In this case you may prefer a perimeter planting of ever­green shrubs or a low brick wall!)

Enjoy outdoor living? The patio can be an extension of your home

Imagine the patio as outdoor living space, not just as a place where you clean mud off your shoes or as a convenience area for haphazard deposits of bicycles, toys, garden tools and the family cat. Most patios today—if governing factors are favorable—are planned as extensions of a living room or family room with sliding glass doors between. This sort of arrangement provides a physical connection so that even when you are indoors you can enjoy the patio; just a few steps put you in one place or the other.

A very small patio slab is seldom satisfactory. Plan one of ade­quate size even if the project must be completed over a longer period of time. The important thing is to arrive at a good design by making simple sketches on paper and work toward it in small steps, if necessary. Sooner than you would expect, the job that looked so big will actually be accomplished, and you'll take a lot more pride in the results.

Why Poured Concrete?

The most common type of patio con­struction is poured concrete. This doesn't mean that you can't use brick, nags, or even soil-cement or loose aggregates. But con­crete is a pretty good step-at-a-time ma­terial for a patio slab because the slab is usually in the form of grids. To make the grids, a pattern of headers is set down and, consequently, you don't have to pour more concrete at one time than one of the grid shapes will take. If the grids are square— 3 or 4 ft.—two to three good wheelbarrows of concrete will fill each, and this is not too much for any amateur concrete man to handle.

Concrete is durable, fluid enough so that it can be cast in curves, flexible in surface texture and coloring. If you want a smooth patio for dancing, a steel trowel finish is called for. A surface to provide traction for footing? Simply finish the concrete with a wood float. Something along deco­rator lines? Washing with a strong stream of water from a hose just before the con­crete sets will expose the aggregates. You can get flagstone effects with a grooving tool or striated effects with a broom.

Gridded concrete patio is not difficult for home crafts­man, adds much to value of house and to living enjoy­ment. Leave a few open squares in patio for shrubs.

Before: This was the view (below) before completion of attractive patio. Over­all plan made it possible to integrate brick veneer­ing, brick planter wall and cast concrete patio in a harmonious project. At this point, concrete footings have been poured for ve­neer and low planter wall.

Hand mixing can be avoided by ordering a load of ready-mix, but be sure to have help on hand when the truck arrives. If you wish, skip the concrete end of the job entirely; you'll still save about 50 per cent by doing the layout and putting in forms. Often, you can save money by working as a helper when you call in a professional mason to do the pouring and finishing.

Grid-pattern headers are usually 2x4s, either s4s (lumber that has been surfaced on four sides) or special lumber which has been planed on one edge only.' Since that finished edge will be the only exposed one, the rough surface on the other three sides doesn't matter. Grid lumber should be fairly good stock; straight, sound, stud-like pieces will be easier to install. Sometimes the headers are sliced in half lengthwise to get two 2x2s out of each 2x4. The 2x2s are set out just as if they were full size (the concrete thickness must still be the minimum 4 in.). There is a saving in ma­terial when 2x2s are used, but small size stock can create problems unless the pieces are amply studded with galvanized nails to keep them from popping up after the pour has hardened a while and shrunk some. The amateur may find that the convenience of working with full-size stock more than makes up for the saving in lumber.

Placing the Headers

Lay out the long pieces first, placing them along lines established with stretched string. Allow for a slight pitch (away from the house) for water runoff. Most often, if excavating is necessary, it pays to dig nar­row grooves for the headers first. Then, after the gridwork is established, shovel out the dirt between down to the full width of the headers.

A patio that will provide years of outdoor enjoyment, this slab was located to give morning sun, after­noon shade. Cover, screen are the Diamond-Rib aluminum panels.

Various header patterns for a patio are shown below. Construct­ing a patio in grids is easy, since each section can be poured in­dividually over a period of time.

The crosspieces, when they are in line, can be end-nailed at one end and angle-nailed at the other. Use 16-penny galvan­ized nails for any toenailing that's done— 20-penny nails for surface nailing. For studding of headers so that the grids will be securely tied to the concrete, use 16-penny galvanized nails.

Where a form board must be curved, substitute 1/2-in. stock which is easy to bend around all but the sharpest curves. The 1/2-in. stock should be doubled. Set one piece first, attaching it firmly with stakes.

Mold the second piece to conform to the curve of the first one and attach it by driving 12-penny nails right through and clinching them over on the side that will be hidden by the concrete.

If your patio project includes things like post lights, a convenience outlet, a cover, a bench or other, similar accessories, plan for them before you start work. Burial cable for electrical accessories can be buried directly under the concrete. Studs for posts can be imbedded in the concrete. A conduit for a convenience outlet or for low mushroom lights can be set in place to bring the cable back above ground. Legs for a permanent bench can be installed before the concrete pour.

Dig trenches for long headers; set in straight, following stretched line. Header braces are cut off below top of header before pouring. Redwood is an ideal header lumber for a gridded patio.

Many patios end up as semi-indoor rooms. Roof, half-walls are of translucent Filon plastic panels.

Underpinnings for permanent bench can be set in patio concrete. When patio abuts house, think of using planters between the slab and house wall.

Braces are hammered solidly into ground, nailed to headers, then cut off at least 1 in. below header surface. For the braces, 3/4-in. redwood is O.K.

Check levelness between headers with straight 2x4 (left). Straighten bowed headers with plane. Headers should end up flush with concrete surface.

Crosspiece is end-nailed through a long header             Form curved edges with flexible ½-in. stock, sur-(photograph below). Use two 20-penny nails for        face-nailing board to header ends. Nail second piece each joint; they should be as tight as possible to first, clinching nails on the patio side.

Narrow headers can be formed with 3/4-in. stock (left). Studding the grìdwork with galvanized nails insures good bond between wood and concrete.

Patio boundary wall can be poured, then slab (leaving joint for expansion), or the footing for a wall to be added later can be poured with slab.

If help is handy, you can buy a load of ready-mix. Everything at site should be ready for pour. Shovel or rake the concrete around to fill grids.

Strike across the grids with straight 2x4. using a slight back and forth motion as you draw the strike board toward you. Wear throw-away boots.

The finishing here is only to level the concrete and fill air holes. The surface will later be broomed and washed for an exposed aggregate effect.

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