How to Form Building Footings

You should be able after reading this, to performfooting including corners. Lapping in and out all the
simple forming methods for linear footings and pierway around. Now start your inside form. Stand the
footings for a basic foundation. I will cover optionalboard 24" away from the outside form board and
ways to form foundation walls as well. Along thehold it in place with either a 28" piece of the 1" x3"
way I will leave you hints that will either be ways tolumber scrap keeping a minimum of 24" between the
save money, safety items or perhaps a reference orforms. The building inspector will check this dimension.
two for you to go to for more information if youHe/she does not care if it's slightly larger but he/she
need it.will fail it, if it's less than 24". Again work all the way
Linear Footing Formwork- Linear footings is a fancyaround your footing until you have a full rectangle
word for strip footings that you may have seenwith a form board for both the inside and outside of
being placed under a new house or garage. They areyour footing in place.
the first basic piece in the foundation system you willNow is the time to begin making your forms strong
need for your project. Linear footings may form aenough to hold the weight of the concrete. Starting
square, a circle, an arc or perhaps just a projectionin one corner, add enough wood stakes, nailing each
sticking out from the main building that will support aone as you go to the formwork with 10 penny
knee wall or a retaining wall.duplex nails. Steel stakes have pre-drilled holes in
Observe therewill be several men involved as well asthem so you simply insert the nail in a hole and drive
the use of wheelbarrows to haul the concrete andit in. Continue this until one side is secured soundly.
place it in the footing forms. Also note the smallNow stand the inside forms making sure you maintain
squares in the center of the excavation are for athe minimum width required by your drawings. Install
pier footing that may support a column later on. The"spreaders" made of scrap lumber across the top of
concrete is placed and leveled off flush with top ofthe forms to hold them apart and help hold them
forms.from tipping over when the concrete is placed inside.
Materials: Materials for footings can range fromContinue on all the way around the footings until all
dimensional lumber such as a 2" x 12" or 2' x10" toforms are nailed and staked. NOTE: As you proceed
plywood, scrap lumber pieces, or any other woodwith the formwork, using your level and tripod, make
you have laying around. Typically, footing lumber cansure the forms are LEVEL! They are of no use if
be used over and over again to save money. 12they weave up and down and will make installation of
penny,10 penny and 8 penny common nails, somethe foundation itself, nearly impossible. If you
string line, pencils, level, ruler or measuring tape and aencounter rock or other obstruction, ask your building
tripod and bubble level. A tripod and level can beinspector how he/she wants to see the footing
rented by the day from most Rental centers. Theyformed at that location. They may allow you to pin
will show you how to set it up and use it if you needthe rebar to the rock, ask that some of the rock be
help. A string line bubble level is approximately $2.00removed to provide a level surface and so on. Now
at most home hardware stores.install the rebar. Just slide the long lengths under your
Tools-Long handled pointed shovels, short handledspreaders making bends at the corners. Using tie
square shovel, hammers, pick, 12 pound sledgewire, hang the bars from the spreaders so the rebar
hammer, tie wire, and a chalk line box.is located within the bottom 1/3 of the footing height.
Reinforcement- In most parts of the country steel12" high footing? Hang the bars 3-4" above the
reinforcement is required in foundation footings. Itground. This will help provide the strongest footing
could be 2-#5 bars continuous or 2-#6's and thisyou can make. When all rebar is complete, call for
information will be shown on your building drawings.inspection and take a rest.
Reinforcement bar sizes are based on 1/8"Placing the concrete-When pouring a large footing or
increments of 1". So #5vbar is 5/8" thick, #6 bar is 6foundation, you will most likely purchase the concrete
8 or ¾" thick and so on. Bars range from #3 tofrom a Redi-mix concrete supplier. They will want to
##24 but will never see anything larger than a #7 inknow, how many yards you need, what strength
any typical house footing. Rebar (for short) isconcrete and what time of day you would like it to
available at home centers, lumberyards and if yoube on site. Have your information ready. Order two
have a local steel supplier in the phone book, theydays before you need it and check again on the day
may deliver as well. Rebar comes in 20' or 30'lengthsit is supposed to be delivered to make sure there will
with 20' lengths which are easier to handle and arenot be any delays. Weather, plant breakdowns and
preferable. You can bend a #3, 4 or 5 in a simple jigeven manpower can sometimes delay truck delivery
made of stacked cement blocks or a trailer hitch ontimes. They will get there as closely to the hour you
a pickup truck. It will take some effort but thererequested as possible. BE READY! When the truck
aren't that many to bend.shows up is not the time to find out you have a flat
Cutting rebar may be done with a demolition saw oron the wheelbarrow or can't find the shovels. Have
a skill saw with a carbide blade although that is muchyour tools and manpower ready. Most companies
slower. WEAR SAFETY GLASSES AT ALL TIMES!allow up to 1 hour on site for unloading. After that
Flying debris from the saw blade and sparks canyou pay additional time charges for the truck and the
cause serious eye injuries. Watch the sparks as well.driver. It can get costly! Unless you are superhuman
Be aware of where you're working and have a firmand very well experienced do not try and unload
footing when doing this work. Make sure no one is10yds of concrete with only 2 people. You most likely
standing in the path of the cutting debris or sparks.will spill more than you use, the concrete will get hard
Rebar installed in a pier footing. Many footings have 2before you finish it and rushing around can cause an
or 3 continuous bars tied together end to end forinjury. Be prepared with sufficient manpower.
added strength of the footing. Walls may have justAfter the concrete is placed in your forms and
vertical bars or both vertical and horizontal bars inroughly troweled off to the top of the forms, take a
them.few minutes break. The concrete will start to setup
Installation: Here's the fun part where you actuallyand if your plans call for vertical bars in the footings
see something getting done. Once you havefor the new foundation walls, this is the time to install
performed the layout of the building lines, you arethose. They should all be pre-made and laid out
ready to start installing the formwork. Remember,roughly where they are to go in the footings. Again,
this is not cabinet or finished work that will be seenplan ahead. You may "stab" these rebar into the wet
later on. It is simply a temporary form to hold theconcrete, wiggling them around slightly to get the
concrete in shape until it dries. When your concrete isconcrete to fill in around the hole you made. Your
hardened, YOU RIP ALL THE FORMS BACK OUT!plans will tell you if the bars go on the inside or
While we are here, when you have finished andoutside "face" pf the wall or in the center and how
poured your footings, remove ALL wood fromfar apart they are to be. "Inside" and "Outside" face
around the work. Leaving wood in place and buryingsimply means the inside or outside of the new all.
it will draw insects and especially termites. They justMost times the bars are to be placed 2" away from
love damp wood. This will be a serious problem laterthe face. Your drawings will tell you this information.
on. Take your time to clean it all out. Start in oneStarting in one corner, install one bar in intersection of
corner of your foundation (we will for now assume itthe corner and then measure whatever dimension
is a rectangle) and start laying out the longest lengthsthe drawing shows for centers. 32" on center (O.C.).
of lumber you have to use. Your drawings will tell youJust measure over 32" and install the next bar and so
if your footing is 20" wide and 10"' deep or 24" wideon. When you come to the next corner, make sure
and 12" deep and so on. The first number given suchone bar is at the corner intersection center again.
as 24" x12" typically means the width of the footingYou can add extra bars of you have a question, just
is 24", and the depth is 12". Typical means this is thedon't add too few.
size used everywhere unless the architect shows aNext day. Now that you found the muscles you
different size in a specific place. If your footing is 24"never knew you had (just a little sore?) it is time to
x 12", you would be using 2" x12" x 12' or 10'strip all the formwork off the footings. Yes all that
dimensional lumber marked as SPF. (Spruce, Pine, Fir).great form work you did is now just scarp lumber
In different areas of the country, faming lumberpile material. Take ALL wood out of the foundation
could be Southern Yellow Pine, white pine or otherarea. Rotting wood underground draws termites and
most common and cheapest wood available.other nasty insects! Footings are complete.
Remember, this is not structural framing lumber soFoundation forms completed and filled with concrete.
there is no reason to buy the highest priced woodNot child's play!
for this work. Buy the Cheapest!Foundation walls: Walls may be constructed of
OK so you worked your way all around the buildingconcrete block units (Masonry or CMU), poured
and find out the building doesn't fit your lumberconcrete, pressure treated wood and today even
lengths. Amazing! Say the building is 42' long. byStyrofoam foundation blocks are available. Whatever
lapping your forms one foot each, you will only getthe type you are using, if you did a good job on
39' from 4 10' pieces and you need 42'. Now you areyour footings and they are nice and level, the walls
allowed to cut some pieces to fit the corners. Try toare going to be easy to install. If your foundation is
keep the cutting to a minimum so you can save yourmasonry, your work is done. Your mason will now
lumber for another project. OK, now we have lumberlayout the wall locations, lay the CMU, pour the CMU
laid out all the way around the foundation. Holding thecells that have the rebar in them and install the straps
lumber in place can be done by several methods andfor the sill plate for the house, shed, garage, etc.
all are fine.Make sure his contract includes all this work and
Formwork can be held in place by using woodenmaterials. If the foundation is concrete, the concrete
stakes, steel stakes, perforated strapping steel tape,contractor will bring all the forms with him. Again,
or wood spreaders. Steel stakes are quicker but aremake sure all the formwork, wall ties, rebar required,
expensive to buy. If you can rent a box of 24 or 48,windows and other accessories are included in his
do so as they greatly speed up the work. If you arecontract. It is possible for a homeowner to form and
using wood stakes you have to purchase some 1" xpour a foundation but it is not child's play. For rentals,
3" x12' lumber for cutting of stakes. If your ground isrebar installation for the walls, actual placement of
very soft or wet, the stakes may have to bethe concrete, how to use the trucks properly and
30"-36" long, if the ground is firm 24" long stakes willpossibly the use of a concrete pump are all best left
do. Cut a point on each stake and make a couple ofto the pros. Concrete is extremely heavy when wet.
dozen of them to start. Stand your first footing formImproperly constructed wall forms can result in a
directly under you layout line and drive a stake"blow-out" of the formwork and serious injury or
alongside on the outside! You have to be able todeath can result.
remove them later. Now keeping the form underFootings are the basic and first building block of your
your layout line, move along the board and placeproject. Sheds may sit only on 4 solid concrete
another stake at the other end keeping the entireblocks but those are the footings. They too must be
length of the board under the string line. Make suresolid and level to provide a good footing for your
your form is in line with the foundation footing layoutshed. Take your time and do it right and the rest of
line. Place your second form alongside the first on theyour building will be easier to keep plumb and level.
outside and lap it 1" over the first. Drive a 16 pennyHopefully this has given you lots of ideas and
duplex nail in the lap to hold it while you work along.information on the right and wrong ways to install
Third form; place it to the inside of the 2nd board,footings. Whether it is a large or small project, the
lapping it one foot as well. Nail these together fromtheory is the same. Take your time to read your
the outside! Continue on around the footing until youdrawings, always use safety glasses when using a
have stood forms for the entire exterior of thepower tool or placing concrete.