Putting Up Posts

THERE ARE many jobs around a house that involve posts of one kind or another. Posts for a wooden fence are the keystones of the project; weakness here and the fence will eventually lean, sag or just fall. A cover over the patio slab (you will surely want to erect one some day to provide shade) requires sturdy posts for support. You need posts for tetherball, a swing, clotheslines, a volleyball net, a driveway light and so on.

Need posts for lights, patio roof or clothesline? Here's how to do it

Patio roof (above) was built after slab; holes were drilled in concrete slab with carbide-tipped bit so L-haped clips which hold posts could be bolted down. Other methods are shown in drawings opposite.
Construct post lights as shown on page 50; use burial cable and check your local regulations.

Regardless of the types of posts you build or install, masonry materials play an important part in providing a strong foundation.

How do you install posts on concrete, a patio slab for example? The method used here will depend largely on whether you plan for the posts before you pour the slab or decide to put them up after the concrete work is done. You can provide an adequate foundation for a post that must bear a heavy load by digging a footing for it (see sketch) as you prepare the ground for the slab pour. The foundation hole should be about 1 ft. square and 1 ft. deep. The form for the concrete is provided by the earth itself, which should be well tampered and cut vertically on the sides. If anything, the sides should slope outward toward the bottom of the hole. Since the post footing will have more weight than adjacent slab areas, you can guard against cracks by using reinforcing steel, bent 90 degrees, to tie footing and slab together. The post can be tied down with masonry fasteners, or by setting a piece of steel vertically in the center of the footing before the pour so that it projects about 3-4 in. Drill a matching hole in the bottom of the post, and set the post over the steel.

Methods of erecting posts on slab. Work must be done before pour unless L-clips are used.

Another method of providing a post foundation is to precast footings and set them solidly in place before the pour. Here, you can use ready-made piers which are available for use in crawl spaces and foundations.

Still another way of erecting a post is to use strap steel bent into a U-shape (or two pieces tied together with steel to form a U) which is imbedded in the slab pour so that the arms project about 5-6 in. After the slab sets, the post is placed between the arms and secured with bolts or lag screws. You must be careful about the dis­tance between the legs of the "U"; use a scrap piece of post to establish the dimen­sion.
Where the slab is already in, you can use any number of masonry fasteners to secure posts. More information will be found in the chapter on this subject.

Holes for fence posts should be 5 to 6 in deeper than the depth the posts will be buried. This is so the bottom of the foot­ings can be lined with gravel or small stones. Most fence posts are 4x4s, so the diameter of each hole should be a mini­mum of 6 in. Digging is easy if you work with a "clam" post hole digger or with a powered auger. There's nothing wrong with digging larger holes except that it involves unnecessary labor and you'll need more concrete fill. If you must work with a shovel, select a scoop type with a small blade and long handle.

After each hole is dug and the bottom 6 in. filled, set the post in place and use a level to see that it's plumb. If you use a stiff concrete mix, it's possible to keep the post plumb without further juggling. If you should have trouble, however, set up temporary braces to keep the post in place until the concrete hardens. Use a short length of 2x4 to tamp the concrete and slope the top to provide a runoff for water. Some professionals will dig all holes and actually construct the fence before cementing the posts on the basis that the fence assembly will keep the posts plumb and in alignment without temporary bracing.

Wrought iron posts have preformed mounting brackets. Matching holes are drilled in concrete, or mounting bolts placed in concrete before pour.

Two ways of making wire hole in post are shown above. Run deep dado in post and partially fill, or put together two 2x4s, each with shallow dado.

Sturdy fence posts are made as at left. For 4x4 post 6 in. diameter hole is minimum; 8 in. is better. Treat the buried section with preservative.

For a post light, you can form a center hole for wires in one of two ways. Run a deep dado (a rectangular groove) down the center of the post and partially fill it with a strip of wood. The opening that re­mains should be at least 1/2 in. square. The other method is to use two 2x4s to make a 4x4 post. Run a 1/2-in. dado down the cen­ter of each post and glue and nail the halves together.

Removable and Portable Posts

To make a post that you can remove, a tetherball or a clothesline post, for ex­ample, use a 5-gal. drum as a form and a length of pipe to serve as a sleeve. The drum is buried a little below grade level and the pipe centered in the concrete used to fill it. Put the post in the sleeve pipe when you pour the concrete—this will make it easy to keep the sleeve plumb. Use a wooden plug in the pipe to keep it from filling with dirt or water when the post is not being used. Be sure the plug doesn't project above grade for people to trip over.

A post permanently imbedded, yet pos­sible to move from place to place, can be constructed in a similar manner. Again, use a 5-gal. drum, but set the post directly in the concrete. The drum can sit above ground or it can heburied. Another method is to use an old automobile tire as a permanent form. Tire posts are good for tetherball and volleyball and badminton nets, especially when the back yard will not permit a permanent installation. Rest the tire on firm, level ground or on a piece of plywood and center a sleeve in the con­crete that you pour to fill the tire. A post constructed this way has ample rigidity yet is easy to move since you can tip it over and roll it about on the tire.

Posts can be constructed of brick, masonry units or stone using the same construction techniques you would employ in building a wall. Posts of this type are, of course, more time consuming, but time is on the home craftsman's side since he doesn't have to pay for his own labor.

"Portable" post (left). Post and base can be left above ground or reburied in new location. Re­movable post (right) is handy for game nets. etc.
Ideas for brick posts: method of casting top; hollow post for light wiring; large post with rub­ble center; solid post; post to take fence rails.

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