If you have a high water table or it has just rained, you may find that your footing holes have flooded with water. This is not usually a problem. Water can be bailed or pumped out, and the soil at the base of the hole can be compacted. The concrete you pour into the hole will displace […]
The weight of your deck might surprise you. Once finished, with a group of people gathered on it for a party or a cookout, a deck could weigh thousands of pounds. Most homes have several continuous foundation walls to spread out the weight of the house on the ground, but your deck may only have […]
Save Accurately transferring the deck post layout from your plan to the job site is critical. Learn how to use stakes and string to pinpoint the deck footings and establish the correct deck post spacing below. Why is Deck Footing Spacing Important? Footings support a deck’s posts and beams and must be spaced and sized […]
Hand digging your footings. Take your time and invest in a post hole digger, which will work better than a shovel to scoop out dirt. You will need to dig and remove soil until you reach the necessary size and depth specified on your approved plans. If you run into large rocks, this can become a very strenuous process. Using a 6′ steel pry bar will help. When the holes are finished, you will want to clean them out by removing any loose dirt and tamping down the base and sides so that they are solid. You can use a shovel and a post hole digger to excavate your footings by hand. The size of your footing will be determined by the amount of weight or load the footing will need to support and the type of soil in your yard. You will need to dig the footings to a depth below the frost line. For example, the footing depth in Atlanta is 24″ deep, NJ is 36″ and Minneapolis is 42″. To be safe, always call your utility providers before you dig. Have your gas, electric, water and other utilities marked before excavating. This service is free and usually requires about two days notice. Cable TV lines and sprinkler lines will have to be marked separately. You may want to create a bell at the base; you can do this by expanding the bottom to the required size. Once the holes are ready, you will want to protect them from collapse until after you have had your footing inspected and can fill them in with concrete. Depending on how you plan to finish your footings, you may need to haul away the excess dirt. Plan for this or you may end up killing a great deal of your grass. Mechanized Excavation Most contractors use front-end loaders equipped with a hydraulic auger to dig footings. You can also rent a one or two person gas powered auger to save you considerable time and effort. With these machines, you can even dig through ice, snow and frozen soil during the winter. You will need to have yard access to drive the machine into position. Fences and certain kinds of landscaping may make this impossible. If you are going to use a machine that you are not familiar with, make sure to read the operating instructions and take proper safety precautions to prevent an accident. Be aware that driving and excavating through grass can cause yard damage. To reduce this damage, you may want to have a couple of helpers lay plywood under the vehicle’s tires or use a track unit. Try to avoid driving on extremely wet yards and/or up steep hills. Even after using a mechanical auger you will still need to use a post hole digger or shovel to finish the job by cleaning out the holes and tamping down the bottom and sides. A solid base of soil will prevent the footings from sinking.
Concrete is, in fact, the most used material for construction in the world and has been in use since the age of the Roman Empire. Concrete is a mixture of aggregate (sand and gravel) combined with water and cement. Depending on the ratio of these parts, the concrete can be stronger or weaker. Concrete hardens in a process known as hydration, which is caused by the reaction between water and cement. Adding too much water can weaken the concrete. For most deck projects, it is practical to buy bags of premixed concrete that are prepared by adding water and mixing. You can use a wheelbarrow and mix with a hoe to a consistency that is able to move and fill voids, but is not too wet and soupy. Hoes work better for mixing concrete than shovels. Renting a mixer can reduce your labor time by half. Be sure to follow the instructions listed on the packaging. It is possible to make your own concrete mix by combining 3 parts gravel, 2 parts sand and 1 part cement, but this requires more knowledge and skill than using premixed bags. Your footing should be at least as thick as it is wide at its base. The ideal temperature for pouring concrete is between 50-90 degrees F.
Save Before you dig your frost footings, you will want to make sure the soil is properly compacted to support the deck load. Often when new houses are built, the process of digging the foundation disrupts the soil and leaves the yard unsettled. This means the entire yard will slowly drop in elevation relative to […]
In order to determine the proper size for your footings, you will need to establish how much total weight they are going to have to support and what kind of soil they are covering. To calculate the load, you should use 40lbs per square foot for live loads (these are variable loads that are dynamic such as the weight of people and furniture) and 15 lbs per square foot for dead loads (this is the weight of the materials used for the construction of the deck) for a total load weight of 55 lbs per square foot.
Your deck footing depth is controlled by two things. First and foremost, you need to have good soil conditions that can support the concentrated load placed on each deck pier. You then must consult a frost depth map or reach out to your local building inspector to find out how far you need to dig down to get below the frost line depth in your town or city. You may wonder how deep the frost line is. It can vary wildly. In the coldest climates in the USA, the frost depth can be deeper than eight feet. In warmer parts of the country, the frost depth may be less than one foot.
Before you can calculate the size of your footings, you will need to know what kind of soil is present in your yard. Most soils can be classified into three categories: gravel, sand and clay. Gravel: This type is primarily composed of small stone pebbles that you can see easily with the naked eye. Gravel feels rocky. You cannot roll this soil into a ball. Gravel will drain water very easily and can support the greatest amount of load (3000 lbs/sq ft). Sand: Sand is composed of tiny particles that are difficult to see with the naked eye. Most sand is tan or white in color. Sand has a rough gritty texture. If you try to roll sand into a ball, it will not hold its shape. If you add water to sand, it will run through very quickly. Sand can support a load of 2000 lbs/sq ft. Clay: You cannot see clay particles without a strong magnification. Clay feels sticky and can easily be rolled into a ball. It doesn’t drain water very easily. Clay can be many different colors depending on what other minerals it is mixed with. It is the weakest common soil type supporting a load of 1500 lbs/sq ft. If you are unsure what soil type you will be working with, always use the worst case scenario, which is clay, to make your calculations.
If your deck will be built above a concrete patio, it is always best to have the deck footings in place before the patio is installed. However, if the patio exists, you will need to cut openings in the patio in order to install your frost footings. Using a sledge hammer or jack hammer can break up the patio, but will leave a broken edge and will likely crack the entire slab.