1. Know the weather. Concrete behaves differently for each extreme of weather. If it’s going to rain, find something else to do on that day. I have been caught more times than I want to remember pouring when it rained afterwards. No matter how good your finisher is, he can’t do you a good job in the rain, and the concrete strength is going to be lessened because of the dilution by water on the surface. Pouring footings with some chance of rain is not the same as pouring a finished product before a rain. If the temperature is dropping below frost following a pour, it can be done with the use of a drying agent. This cost extra money, and doesn’t always render the desired results. If the weather is extremely hot, the concrete is going to need more water to keep it from setting too fast.

2. Have enough help to do the work. This sounds simple enough, but an extra two men is much better than one man short. I have been caught with too little help and concrete on the job, with nothing to do but put it down and fight. Concrete doesn’t abide by your time, but its own. On the farm we knew that when the corn was ready to pull for eating and putting in the freezer, we had to get it. It wasn’t a job you could allow to go until you had time. Concrete is the same way. At least with the corn, we knew we had two or three days. Based on the weather, concrete can set before you can get a drink of water. Limit the amount of concrete you are pouring to the number of people you have. If you are doing flat work (driveways, sidewalks, decks), three or four people (who know what they are doing) can handle ten to twenty cubic yards easily in moderate to hot weather. If you plan to pour 100 yards, that number would increase to six or eight. My suggestion is to get a reputable concrete contractor for any large pour you might attempt.

3. Be sure the area you are pouring has sufficient compaction to hold the weight of the traffic that will come. Concrete is tough stuff, but won’t last with inferior material beneath. Most residential work makes it cost prohibitive to have compaction tests run for driveways and the like, but, if there is any doubt as to the compaction, it may be necessary to compact with a vibratory roller.

4. Know where the water will go when the concrete is poured. You don’t want a bird bath when it rains. No outside pour should be flat. Use a level, transit level, or laser level to determine which way to turn the water.

5. Order enough concrete to do the work. If you come up short on a pour and have to wait for more, you have a cold joint where the materials will set up differently and cause a weakened area. This is true especially in hot weather. Calculating concrete is based on area x thickness. Most sidewalks are 4” thick, and paving can be 4” to 6” or more. For residential, high traffic areas with heavy loads, I recommend 6”.

6. Don’t skimp on the strength of concrete. To go from a 3,000 psi concrete to a 3,500 psi will cost a few dollars, but it is worth it in the long run. On very critical high traffic areas, 4,000 psi might serve you better. It use to be a requirement for footings to be 2,800 psi, but 3,000 has become the standard for most footings and foot traffic slabs.

7. All large pours of flat work should have control joints. Concrete is going to crack, but you can control the cracks to some extent by saw cutting or tooling in control joints. The idea is to make blocks that are the same dimension in both directions. For instance, a 10′ wide driveway would be tooled every 10′ across. It sounds simple, but every situation isn’t a rectangle, so you can’t always have perfect square areas. If you have a 20′ wide driveway, you might consider a center control joint to keep your squares to 10′ x 10′.

8. Use reinforcement where it’s needed. No matter what strength your concrete might be, given the right weight of a vehicle it can break. Many driveways are poured with no wire, and some hold up okay as long as large trucks don’t cross them. It is always a good idea to use wire where auto traffic occurs.

9. Don’t add more water than is necessary. Concrete masons have a habit of getting the truck driver to add water the minute he drives up, even before they see the consistency of the material. It makes perfect sense to want it thin so it can be moved and placed easier, but that extra water dilutes the strength. Water is the critical factor in every mixture. The best concrete has the minimal amount of water required. As I mentioned earlier, sometimes it is necessary to add water in hot and dry weather, but even that should be done carefully.

That’s my nifty nine tips. Talk to you later.

Unless you are using a pick and shovel to do the footings, it may be best to have a professional do the work. Take it from someone who has dug footings by hand, the cost is worth it to rent equipment or pay someone else.

Width and depth of footings are controlled by varying climates and soil conditions. Your footing should be below the frost line. Here in the south, that is about eight inches and requirements usually call for the shallowest to be twelve inches below finished grade. Another factor is the soil material and compaction. It is great to have your footing sitting on virgin clay, but that may not be possible. We won’t go into those requirements for this down and dirty (catch the pun) calculation. If you are working from approved plans, the requirements should be there.

A rather standard footing is 24” wide x 8” deep. If we are building a 40’ square building, the math is 160 x 2 x .67 = 214.40 cu. Ft. Now, divide by 27 (the number of cubic feet in one yard), and we get approximately 8 cubic yards of concrete. Keep in mind, there is a large waste factor with concrete (especially if you do not have uniform ditches). Many people calculate 20 percent more for that, but that is high if you keep your ditches uniform. If you were ordering material for this job, and of course, if the footings were dug uniformly, 9 yards of concrete would probably be what to order. This is more in line with a 10 to 12% waste factor. Never skimp on concrete by ordering less and hoping it will be enough. When the plant has to send another truck out with a half yard, they generally charge you extra.

Steel required in footings will vary for the same reasons as depth and width. You should estimate it based on getting 18’ from a 20’ bar times the number of bars required. Each rod has to be lapped by the next bar and tied with wire, thus you don’t get 20’ of running footage from a bar. Rod chairs, those little wire things that hold the bars of the ground, are figured about every four feet of footing. It is very important to keep the steel in the concrete.

Grade stakes should be driven into the center of the footings about 6 to 8 feet apart. Shoot the top of the grade stakes to make sure they are all the same level. You can buy short pieces of rebar for your stakes, don’t use wood. If you are going to have a block foundation, the top of your grade stakes should be in multiples of 8 inches below the top of your foundation.

Because it is easier to build up mortar under a block than it is to take off part of the block, most contractors will hold their grade stakes down 1/4 to 1/2 inch.

Although footings are not a finished product, it is important to keep them smooth and level for the person working behind. Laying brick and block on rough concrete that is high in some areas and low in others presents obvious problems for the mason.

Talk to you later.

Let’s look at different views on the gravel or sand underlayment. The old time way of placing gravel was done after plumbing, which is the more proper way. Many contractors will put the gravel in after they pin the corners, and even before the ditches are dug. The reasoning is simple, it’s a lot easier to place gravel on a piece of ground before you have forms set and ditches dug, and it takes less time. Usually, the plumbing is not in at this point either, making it harder on the plumbing contractor. He not only has to dig his ditches, but he has to roll the gravel out of the way first, and then put it back, too.

Another way that is a hybrid of the first procedure is to dig the footings, put the plumbing in by measuring off the string lines for the slab, and then add the gravel. This is some better than the first way, but the gravel gets shifted around some during the form setting, and it has to be rechecked before the pour anyway. Also, the plumber is a lot more likely to miss on his layout trying to pull measurements from a string rather than a form board.

The oldest way and, to my way of thinking, the best way is to dig all ditches and set all the forms except for a section large enough to get inside with a backhoe or bobcat. The plumber can dig and place his piping and can pull strings to make sure his floor flanges are at the right height. He can compact his backfill and feel pretty good about all his dimensions.

After the plumbing and any other trades are finished laying their work, bring in the gravel or sand. Some contractors prefer to stay with gravel, but there are several substitutes that work better. Sand is good because it is easy to move and can be graded more accurately. A couple of other materials are available in some areas that are cheaper than gravel and sand. This is dependent upon where you live, but if there is a quarry near you, there are some byproducts left from making the gravels that can be used. These are basically materials that are too small to be classified as stone or gravel, and the materials spread well and stay in place. These materials go by several names, so you just need to ask the truckers that haul materials to find out what is available.

After the underlayment is in and the termite treatment is down, you place the poly and then the steel. If you are using wire, that will go in last.

I suggest checking the grades on the top of the forms just before the pour. It is best done with a laser level, allowing one person to do the checking. If there is much variation (more than 1/4”) adjust all the forms to the lowest place. This can be done carefully with a sledge hammer by bumping down on the stakes. Check for square and dimensions one more time.

Pouring concrete is best started early on a house slab to give finishers plenty of time to get a good finish. The preparations with termite treatment, poly, steel, and wire are best done close to the time of the pour. Nothing is much worse than getting your prep done and then having a torrential downpour right after. You end up pulling steel, wire, and poly out so you can clean out the ditches from the washes. If you have possible rain in the forecast, it’s better to wait about the prep work until the morning of the pour.

You should always put your name in the hat a day earlier to get concrete on the day you need it. Do this before you prep the slab because concrete companies sometimes get booked up and won’t be able to delivery the day you want. Tell the plant you want to be on “will call” for a certain time, and then you don’t run the risk of having concrete show up before you are ready for it. Of course, you will have to call the day of the pour to give the the go ahead or cancel the pour.

Have anchor bolts ready to place along the perimeter walls after the concrete is poured. When you pour a monolithic slab, you have the advantage of marking the forms where you have exterior doors so you don’t put an anchor bolt in the middle of a door (and, believe me, it will happen). If you really want to get the anchors in the right places, you can layout your stud framing on the forms so that every bolt should not be under a framing stud, tee, or corner.

We’ll talk more on concrete work later.

There are two important things to do before you set any forms. First, you should double check all your dimensions and the squareness of your layout, along with setting up your transit and making sure the top of your batter boards are still level. No matter how careful you are when you lay out your building, things have a tendency to move. If you pull strings one day and come back the next to dig and set forms, there is a possibility that some knot head may have monkeyed with your stuff.

The second thing to do is tighten the string lines because they will stretch and sag.

Rip 1/2” rigid insulation boards length wise wide enough to go from the bottom of the ditch to above the bottom of the form. This is primarily to keep concrete from going around the stakes, making it impossible to get them out later. It also acts as an insulator to keep the heat in that is radiated from the slab. When the slab is being poured, one person needs to be on the outside pushing dirt behind this insulation as the concrete goes in the footing to keep the board from breaking through. Some people use plywood for this, but that is something else that is hard to wreck out after the pour, and you do not want to leave wood in the ground to draw termites.

If you’ve ever tried wrecking forms without the barrier, you know how important this insulation board is. Stakes that have concrete all around them are almost impossible to get out after the concrete sets. Some people pull the stakes out while the concrete is setting, leaving the form with nothing to hold it in place. I don’t like this because people stepping on the form may push it down and create dips in the slab on the edge.

If your bottom of footing to top of slab is 20″ and your form is 12″ high, you should be able to make your insulation board about 10″ wide to give you enough to come up past your bottom 2″ x 6″ and fit between the stake and the form.

As I mentioned in part one of this article, you will need three stakes to hold a form that is 8′ long. If you do not have the form with the brick ledge, you will need four stakes because there is more give in a 2″ x 10″ than the brick ledge form.

The width of your form determines where you drive your stakes. If you have a form that is 6″ wide, add 1/2″ to that for the thickness of your insulation board and that will be the measurement from the string to the inside edge of your stake. Some people put a level on the stake to be sure that it is plumb, and this is a good idea as it helps to keep your forms straight and accurate. Tack the insulation board to the stakes after they are driven in and you’re ready to set forms

Setting forms is best done with two people, as I mentioned before, but can be accomplished by one. I prefer to use double headed nails to attach the stake to the form. This makes it easier to wreck the forms. Use the gauge to make sure you are 1/2” below the building string. Put a nail in the top 2” x 6” and also the bottom one. The form may not line up exactly with the string, but we will handle that when we brace it off. It is better for the inside edge of the form to be a little outside of the line, rather than to the inside at this point. Because you have an extra 1/2″ between the stake and the lower 2″ x 6″, you may need to put a scrap piece of the insulation board between the stake and the upper 2″ x 6″.

Another item you might use at this point is the laser level. If you have access to one, it simplifies the process of getting the top of your form to where you want it. Instead of gauging from the string, you have a more accurate leveling process with the rod and target. If you have never used the laser level, it is very simple and easy to operate after you set it up.

After you complete a wall from one corner to the other with forms that are nailed off, go back and line the forms to the string by driving a short stob on the outside and cutting a kicker to go from the ground at the stob to the top of the stake holding the form. Angle a nail at the bottom of the kicker back into the stob, and then push the form in line with the string and nail it to the stake. Be sure the stob is far enough from the ditch that it doesn’t cave in when the stob is driven. The form may not be exactly plumb because stakes have a tendency to shift when you drive them into the dirt. This is not critical as long as the variance is minimal.

Set the other forms around the building in the same manner.

Next time we’ll talk about the last preparations and the pour.

From a cost and time standpoint, the monolithic slab is a good way to go. Because you don’t need a block mason, you have one less contractor to bother with.

Usually the footings for a monolithic slab are narrower than for the conventional. Some designs call for a 12” wide footing. If the pad is graded level, most footings only measure 20- 24” from the top of the slab to the bottom of the ditch. Your building plans should specify this.

Monolithic slabs require carpentry skills to build forms and set them to grade. Some of the concrete subcontractors are highly capable of doing this work, but it is usually best to get carpenters involved. If you plan to do the work yourself, that is why I wrote this article. If you are setting forms yourself, it is much easier to do it with at least one person to help. I have set them on my own, but it is difficult and slow.

If you are bricking the outside of your building, a form has to be built to allow the concrete to go under and past the line of the exterior wall for a footing for the brick. The usual way to do this is to make a form that is at least 8” high and 5” wide. It is best to build with the brick ledge added, even if you have no intentions of bricking the building. It is much harder to add a footing at a later time, should you decide to add brick veneer later.

If you want to forgo the brick ledge, the forms can consist of 2″ x 8″s or 2″ x 10″s. This saves about a cubic yard of concrete for every 54 feet of exterior wall.

NOW, let me tell you how I prefer to do it.

If the building will have masonry veneer, or if there is a chance it might have sometime in the future, dig the footings 16” to 18” wide. The person digging the footing should center the ditch under the string that is for the building line. The reason for the ditch being wider than the plans may call for is two fold. First, when the forms are set in place, it is much easier to put the rebar in the ditches. Secondly, there is more room for error if the ditch isn’t completely accurate. If you are not putting the brick ledge in, typical designs call for a 12″ wide footing. Digging the footer wider just gives you more room to work when driving stakes.

Build the forms to be 12” high. Using 2 – 2” x 6” with 9” long blocks between them. Then, put 7/16” OSB on one side that will face the interior of the slab. If the forms are made 8’ long, they are easy to handle and set in place. Blocks at each end and one in the middle are sufficient to hold the concrete. Some people prefer the forms to be only 8” high. I prefer 12” because that generally ensures that your brick will start below finished grade, and the concrete beneath will not be seen. You will need enough forms to completely go around your slab.

With ditches dug and building lines pulled, you are ready to set forms. Before you do that, let’s consider a few things. The best way to make sure that forms do not touch building line strings and cause them to be inaccurate is to gauge the forms below the strings. A small piece of ½” plywood works well for the gauge, as it can be dropped in your tool apron and retrieved each time you are ready to nail your stake to the form.

Your building strings should be to the outside of your exterior walls, so the forms will line up with the strings and be set to the outside of the building. It will take three stakes to hold up a form. If you are building on firm ground, an 8’ 2” x 4” will yield 3 stakes 32” long. Cut sharp points on one end of each.
Your stakes should be located strategically so that the two on the ends will measure 8’ from center to center. This is done so that the next form that abuts can be nailed to the same stake. Turn the 3½” side of the stake parallel to the string line. Measure 6½” from the string line to the outside of the building and drive the stake plumb into the ground. (Please, don’t call it level. Level is horizontal. Plumb is vertical.) Be sure not to drive the stake below the top of your form.

Next time we will look at setting the forms.

If the grade is extreme, the slab is not cost feasible. You should consider the wood floor over a crawl space. With the wood floor system, you have the added area under the house to put things. (Usually, things you will forget and never see again.) Also, from a termite control standpoint, it is easier to retreat later with a crawl space.

Plumbing is also easier to maintain with a crawl space. With slabs, plumbing pipes are sometimes bumped and moved during the pour. Those mistakes have to be dealt with after the concrete has set. With a wood floor, the majority of the rough plumbing goes in after framing assuring less chance of error.

Disadvantages to wood floors are the inevitable creaks and pops caused by curing, changing temperatures, moisture and gremlins. If you have a water leak that you are not aware of, as in a slow leak, the wood may rot. Even with plastic on the ground under the house, temperature variations can allow condensation and decay, especially in areas with high ground water.

If you have a level grade, slabs are the usual choice because of cost. Floors don’t squeak. One thing that I like is the close proximity to the outside elevation. If you have to jump out a window, it’s not that far to the ground. When we get to the point in life that we can’t get around as easily as we would like, climbing a lot of steps just to get in the house becomes a challenge.

In a traditional slab, the blocks are lain on a footing the same way as you would with a wood floor system. The only difference would be the final block course which would be a header (or form) block. Inside the foundation, the ground should be approximately 8” below the top of the header blocks and compacted to about 95%.

Depending on how the building will be framed, cross ditches may need to be dug for grade beams beneath interior walls. If you are working from plans, these will be indicated. Also, they need rebar and rod chairs the same as the footings. This will need to be done after termite treatment and 6 mil poly have been installed.

After plumbing is roughed in, along with any electrical or HVAC that may be necessary, 4” of gravel or sand should be placed over the whole interior. All plumbing lines should be at least 12” below the top of the block work to allow for cross ditches. If gravel is used for the fill below the concrete, it just has to be placed and graded to 4” below grade. If sand is used, it should be tamped with a plate tamper.

Always have your slab treated for termites, unless it is going to be a very small temporary structure. Everyone tells me that the current chemicals used are not very good. However, if you don’t treat it’s the same as yelling “supper time” for the little varmints. Prior to digging footings, you should remove any tree stumps and other wood materials that attract the termites. After the pre-treat, you should not disturb the material below the slab again.

Place 6 mil polyethylene over the entire area, lapping the edges by at least 12″.Holes that are cut for plumbing pipes should not be excessive.
Now the decision comes for reinforcing wire or the use of fiber in the concrete. I have done both, but probably prefer the wire. If you are planning on the fiber at least use wire where you will have exposed concrete, such as porches and garages. The hairy fiberglass that sticks out of the concrete is difficult to get rid of, and is obtrusive. I have actually gotten the stuff in my foot by walking over it barefoot.

Place any other steel for cross ditches, and you are ready to pour.

Watch the weather, and plan the pour. Be sure to have enough finishers to do the work.

During the pour, you will need to place anchor bolts around the perimeter to attach the rat sill (or bottom plate) of your outside wall. How often they are placed is determined by your area. Other than actual bolts, there are some other alternatives that work well. Simpson tie makes straps that are poured into the concrete and wrapped over the bottom plates.

Talk to you later.

Fortunately, in all my years in construction, I have never been in a situation where anyone was seriously injured. But, one wrong move and that can change.

Here are my top safety tips for you:

1. Take care of your equipment. Frayed electrical lines, dull saw blades, worn ladders, etc. are generally the things that will get you hurt. Every construction worker should realize that a part of every work day has to be devoted to making sure all tools and equipment are in good shape.

2. Work in a clean environment. You may not sweep the floors every day, but you can make sure that any materials to be reused are put in a designated place. Boards with nails protruding are one of the largest causes of injuries for carpenters. Every trade that works on your job should clean up HIS mess on a daily basis. It is one of the hardest lessons to teach, as I have seen on large projects and small.

3. If you are digging, be sure to have all buried utilities located first. It is a free service in our area, but you have to give them 72 hours after your call. This delay is probably the best one you’ll ever have in construction.

4. When working up high, take proper measures not to fall. Why do you think roofers pay such high insurance rates? If you are working on a roof, tie yourself off or pay the dough for a lanyard and line. A fall from twenty feet or so can be deadly. With scaffolds, most do it your selfers are going to use wooden boards to walk on. Be sure that those boards don’t have large knots in them. Use handrails for those dangerous heights.

5. If you don’t know how to do it, learn about it before trying. I’ve never felt you could read a book and suddenly know all the answers to doing anything. You may not even know what problems you can have until you are involved in the task. You should be able to determine what the primary safety issues are before starting. If it is dangerous and you don’t think you can do it, don’t.

These are, by no means, the only safety concerns you should have. Most of safety is common sense. Think about safety every day you work in construction, just as you should each time you drive a car. We all make mistakes. The fewer you make in construction, the more fingers you keep.

The lectures were good.  The displays were great.  It was a well thought out and put together series of meetings.  After several warm up speakers, we were introduced to the featured speaker.  His credentials were impeccable.  He worked as safety administrator for a large Alabama construction company.  He had many stories of horror about the carelessness of workers in the industry.  Stories of maim and death.  All of this made me realize that I had personally taken risks with my own well being over the years.  It made me want to go back to my company and fire personnel up to be more careful, not only for themselves, but for the ones who subcontracted or worked under them.

It was either day two or three, and I was driving to the meeting place in the morning.  As I cruised along I kept watch on the parking lot across from the building where the conference was being held for a parking space.  At that time an individual decided it was important to cross the street against the light in front of me.  Being as careful as I was, I quickly slowed to prevent an accident.  I thought of the things we had been learning and how that probably caused me to be more wary of the situation.  Then I looked to get a better view of the jaywalker.  And, yes, it was the featured speaker!

Don’t just preach it, practice it, too.

Talk to you later.

If you have 40 pallets sitting on a job, the mason’s helpers who take the brick from the pallet to the mason are going to grab the bricks that are closer. It’s a natural tendency for a person to do the least work necessary. If 40 pallets are broken open and you only need 30 to do the job, you have quite a lot of bricks left.

The brick company will pick up left over full pallets and give you credit for them, they won’t pick up broken pallets. It’s a double expense to you because you will buy more brick than you need, and you will have to pay someone to move the leftover brick.

It takes approximately seven modular brick to cover one square foot of wall space. Brick salesmen generally ask you to figure seven and one half, but I’ve found that, if the brick aren’t damaged extensively on the pallet, seven is enough. Another contributing factor to the amount needed is the person laying the bricks. If you are paying for the work, make sure you pay for bricks lain, not how many disappeared from the stack.

Simple math for the estimate goes like this; length x height x seven. For instance, if you have a square building that is 40 feet on each side and the measurement from the footing to the point where you will stop laying is 10 feet, the total square footage is 1600(40 x 4 x 10). Next, take out square feet of space in the wall for windows, doors, and other areas that will not receive brick. Subtract that amount from your total and multiply by 7. This gives you the net amount for calculating mortar and sand.

Rule of thumb is 7-8 bags of mortar per one thousand brick, and one yard of sand for three thousand brick. Wall ties are calculated at one hundred per one thousand brick. All of these are simple calculations, and should be very close to the quantities you will need.

If the brick you use are not modular, everything changes. Keep in mind that a modular brick covers a space of 2.67 inches x 8 inches. If your brick is larger, that has to be taken into consideration. When choosing brick, keep in mind that most masons charge more for bonus or queen size brick.

Because larger brick do not have a standard, it’s a little harder to calculate quantities. The amount of mortar and sand goes down some, and the brick usually are figured at 5.5 per square foot.

When you have estimated your job and are ready to order materials, it is a good idea to not bring in all the brick at once, if it is going to take more than one trip with the brick truck. The same goes true for mortar. You must asked your brick company how many brick they deliver at one time.

As I said before, too much stuff on the job will only lead to more waste. You may find wheelbarrow loads of mortar dumped out at the end of a day’s work because the mason had too much made up. Brick are sometime covered up with dirt, and if you don’t count what is in the wall, you may pay for more than you have lain.

None of this is to say that people are corrupt, things have a way of getting out of hand without some supervision of the work. This is true with any construction project. When you are paying for something, you have every right to keep tabs on it.

Before the mason runs out of brick and mortar, do another calculation of what is remaining to lay and subtract the brick you have on hand. This should be done when the mason and crew are not on the job so you can get an accurate count. If you do this, you may find your earlier calculations were off some. You may need less brick to finish than you estimated, and you want have too many brick shipped on the last load. If you need more than you estimated, you can make sure that the extra is added to that shipment. Brick companies usually reserve more brick than a project will take, to cover miscalculations.

Cost for masonry work varies from one location to another. If you are hiring the work, get three prices for comparison. Also, see some of the work that has been done by each mason, because there can be a wide range of acceptable masonry work.

Masons don’t always do their own cleaning, but they usually know who you can call to do the work. Some people don’t want their brick cleaned because they prefer the rough look. If you intend to clean yours, have it done as soon as the work is finished. The longer mortar stays on the face of bricks, the harder it is to get off.

You may want to lay your own brick. If you are not accustomed to hard work, I recommend against it.

Talk to you later.