The advantages and disadvantages of strip Foundation
Strip Foundation is a monolithic strip of concrete, passes under all bearing and inner walls of a building or buildings. Strip Foundation is used in the following cases:
- For buildings, created from durable, heavy materials – brick, cinder block, concrete etc.
- For buildings, that have a heavy overlap
- On the ground, dominated by inhomogeneous soil
- In that case, when the layout of the building provides underground garage, the basement or ground floor
Advantages of strip Foundation in the following:
- The ability to withstand high weight loading of construction
- The ease of creating a Foundation with his own hands
- High service life of the Foundation
- Difference types of strip Foundation, suitable for different size of the purse
- Special technique can not be applied
Among the main disadvantages of the isolated:
- High volume of work
- Strip Foundation not suitable for all types of soil
- High consumption of materials
The device strip Foundation
Strip Foundation may have a different depth. If it is built for a cottage or other "heavy" buildings, the depth of the Foundation should be more depth of soil freezing on 20-30 cm, this Foundation is also called recessed. For wooden buildings and the inner walls of the Foundation can be within 60 cm deep, and this type of Foundation is called a low-depth.
Strip Foundation is divided into several basic types:
Monolithic, created from reinforcing dressings and concrete solution. This type of strip Foundation is the most durable and long lasting, because. does not consist of designer, similar to precast strip Foundation. The lack of a monolithic strip Foundation is the highest material cost of materials, as well as the complexity of work on pouring the Foundation.
Precast Foundation. Created from cooked plant concrete block, which are delivered to the construction site of a building. Units are installed in the trench close to each other and the joints are smeared with a solution, which serves to strengthen the Foundation and waterproofing material. The precast Foundation it is not recommended to install on pocasi rocks, because. will possible rupture of the joints of the blocks, causing to deform the whole Foundation (will be like a zigzag) and the whole structure can collapse. One more unpleasant nuance precast Foundation it is the increased material costs for special equipment: the crane for lowering blocks. Among the advantages of the units emit an increased rate of establishment of the Foundation and the decrease in expenses for raw materials (blocks cheaper than pouring a solution, in addition, the blocks can be set by leaving voids, and this +20% save).
How to make a concrete solution for the strip Foundation?
From the concrete solution depends on the quality, the strength and durability of strip Foundation, the strip Foundation depends on the durability of buildings. Based on this, it should be noted, that in no case can save on the concrete solution, and even more unfair to put him. Actually because of this it is recommended to create a Foundation with his own hands, because. many firms are trying to make more money, using cheaper cement, pulling at least a deep trench, etc.
The main components of concrete for any Foundation is water, cement, gravel and sand. It is also possible to use various additives, for example, for faster setting mortar.
It should be noted, what are the components of the concrete mix should be of high quality. The water should be clean, without impurities. Cement you need to choose: for lightweight structures will fit the M200, for more permanent structures M300 and above. The sand should be without clay, pebbles and various debris. It is better to use river sand, which additionally need to sift sieve. To rubble no special requirements, the main thing, what would its size was optimum – not too big, but not too small.
As to the ratio of sand/cement/gravel, you must adhere to the following proportions – 3/1/5. Based on this, it should be noted, that gravel should be more than the sand (about 2 times, allowed a little less), and the water should be more cement (60%).
The mixture should be kneaded in the mixer, to be purchased before construction. Her price is inexpensive, and there is also the option of creating your own hands, and quite simple.
There 3 features of mixing concrete and mortar, you need to consider:
- If you pour the Foundation in the cold weather, the water to be heated, so the solution faster grab
- In hot weather, on the contrary use cold water, otherwise, the rapid grasp of the solution can lead to the formation of adverse cracking
- As previously mentioned, that water should be more than cement, you need to consider, the wet sand is full of a certain quantity of water. Many builders forgets about it and the result is a very rare solution.
With a solution sorted out, go to the instructions for the creation of strip Foundation with his own hands.
Technology of creation of strip Foundation with his own hands
Technology of creation of strip Foundation with his own hands is not too complicated, but requires the execution of each stage in good faith. So, let's get to it:
- Create drawing a scheme of the future Foundation with all the exact dimensions. Calculate the required amount of materials.
- Prepare the area: we remove all garden debris, flatten the hills and pits, if possible. The size of the stripped area should exceed the perimeter of the Foundation on 2-3 meter on each side.
- Mark out the area of the future Foundation with the help of pegs and ropes. Strictly adhere to all dimensions and angles.
- Escaping the trench. Its width may be different. If in the future will be a brick wall – at least 50 cm. The depth of the trench is determined depending on the type of construction and the availability of future garage or cellar underground. If such a structure will be present, the Foundation will serve as a wall for him, so it will need to do high. The trench can dig himself by a shovel, and special equipment – mini-escalator.
- Once the trench is dug, carefully stamped the bottom and create a drainage layer. It is necessary to create sand (10 cm layer thickness) and gravel (too 10 cm). First, fill it with sand, fill with water and carefully stamped and align. Further, in the same way to create a pillow from rubble.
- After, as a drainage layer will be created, move on to the waterproofing. It is recommended to use roofing felt. The same roofing material to cover the walls of the trench, that would not prevent the spillage of soil on Foundation.
- Go to the gradual pouring of the Foundation. The first layer (about 10 cm) poured on the drainage layer with waterproofing. Wait for the mortar to grab. This first layer of concrete, in fact, the same is the waterproofing of the underlying soil.
- Next, collect the formwork, which is used to create a strip Foundation. The width of the formwork for the inner walls defines the width of the Foundation. To create formwork choose planed one side boards (internal), wide 3-5 cm. In order, what would the formwork is not crushed by the action of the solution and soil, create special spacers. Formwork height above the earth's surface shall not be less than 30 cm – height plinth.
- Created in the formwork placed reinforcement. The bars placed horizontally and vertically around the perimeter of the Foundation. The rebar is clamped between the wire or prihvatyvaya welding. The spacing of vertical reinforcement rods shall be not less than 10 cm and not more than 25 cm. The purpose of the reinforcement – improving the strength of the structure.
- Formwork concrete solution. This should be done correctly. The solution is poured layers, each of which is not more 20 cm. After each pour,, the concrete compacted, it strikes a metal bar in different places and additionally rattle for external walls formwork. These activities are necessary in order, remove the air, which can be formed in the solution.
- When the strip Foundation will be completely filled, leave it up to the full setting solution. The formwork is recommended to be removed a week after the fill.
- After removal of the formwork, external wall strip Foundation is necessary to protect waterproofing layer. To this end, the Foundation is coated with bitumen mastic, possessing good adhesive properties, and on top of mastic superimposed sheets of roofing material.
- After, as the sheets are securely glued to the Foundation, it is necessary to produce a finishing action – backfill, which is, the space between the ground and the Foundation is backfilled sandy layer, which is wetted and compacted. At this, the final stage, care should be taken, that would not accidentally disrupt the waterproofing layer!
Here are some illustrative video lessons on creating a strip Foundation:
That's actually the whole technology to create a monolithic strip Foundation with his own hands. If you do these steps carefully, not saving on building materials, the Foundation can last you for more than half a century! Do not forget, that Foundation repair is a very time consuming process and also materialozatratnym, remember, that the avaricious pays twice!
We wish you good luck in making garden buildings with their hands!