Column foundation - one of the types of foundations, which is a good alternative, and sometimes the only option for building a house. It is a foundation that is built on buried pillars made of various materials. In some cases, this foundation is much more economical than a strip foundation, moreover, it can be used on "difficult" soils with high humidity, subject to heaving.
The columnar foundation is well suited for individual construction, has sufficient bearing capacity, and allows you to build houses of wood, frame and panel structures without a basement.
Why choose a columnar foundation:
Its cost is, as a rule, no more than 18% of the cost of the entire house (for comparison, the cost of other types of foundations can reach 30%).
Column foundation is not recommended to be installed:
Supports for columnar foundations can be made of various materials that differ in their strength and cost. The choice of this or that material should be determined, first of all, by the construction of the house (its mass and number of storeys).
Add 30 cm to this value and get the installation depth of the supports.
2. The preparatory stage includes clearing the construction site and removing the vegetation layer of the earth (this is about 30 cm of the top soil layer). At this stage, the construction site is also cleared of foreign objects and leveled.
If the soil under the cut layer mainly consists of sand, then additional filling is not required. On clay soils, you need to equip a sand cushion.
4. The next stage begins the breakdown of the columnar foundation, when the house project is transferred to the area. Supports are placed around the perimeter of the house, at the joints of the walls and in places of greatest load.
When marking the future foundation, it is important to control the angles of intersection of the threads, at the corners they should be exactly 90 °. The meta of the installation of the pillars is noted, it is important that they are located at a distance of no more than 3 m from each other.
Then we proceed to actually dig holes for future supports. If the depth of the pits does not exceed 1 m, then strengthening their walls will not be required. At greater depths of the holes, it is necessary to install a spill protection.
The depth of the pits should be made taking into account the fact that the bottom of the pit under the columnar foundation is filled with a layer of sand at least 10 cm thick. The width of the pit is 20-40 cm larger than the width of the foundation itself.
The sand pillow at the bottom of the pit is compacted and lined with roofing felt or polyethylene to prevent water from leaving the concrete poured into the pit.
At the next stage, we proceed to the arrangement of the formwork. It is made of boards or metal.
If the edges of the pit do not collapse, then instead of formwork, polyethylene or roofing material can be used. Also, the function of formwork can be performed by pipes made of iron, asbestos or ceramic.
The most preferable formwork is for a columnar foundation made of raw narrow wooden boards. To preserve the binding properties of concrete and prevent the release of water from the mixture, dry boards are pre-soaked.
The height of the posts is adjustable at the same height.
Depending on the selected technology, a monolithic, prefabricated or prefabricated monolithic grillage is distinguished.
When installing a monolithic grillage, you can be sure of the rigidity and durability of the foundation being erected. Before pouring the concrete mixture, it is necessary to install the reinforcement cage and connect all the jumpers of the supports of the column foundation to it by wire twisting or welding.
Further along the entire perimeter of the foundation, the formwork is mounted and the concrete mixture is poured. After pouring, the concrete grillage is insulated in order to avoid atmospheric influences, and left to gain strength for up to 28 days.
After that, they begin to install floor slabs and actually build a house, this foundation is perfect for a frame house, while this foundation is easily made by hand.
Since in many regions the underground space of the house needs additional insulation, when erecting a building on a columnar foundation, one should not forget about the device stage zabirki - the enclosing wall between the posts.
The zabirka is designed to protect the space under the house from litter, precipitation, etc. It it is laid on its own base of concrete screed and made at least 40 cm high and depends on the height of the building's basement. The pick-up is not associated with the pillars.
An important step is the waterproofing of the columnar foundation. It is carried out using two layers of roofing material overlaid with bitumen, or cement mortar with sand.
( 2 marks, average 4.5 out of 5 )
Posted By: Work Style |04, Nov 2020
Posted By: Work Style |04, Nov 2020
Posted By: Work Style |05, Nov 2020
Posted By: Work Style |09, Nov 2020