Practice shows that when erecting any structure, about 1/3 of all construction costs are spent on mounting the base. Considering that this stage is the most expensive, the right choice of the type of foundation and methods of its arrangement allows to significantly adjust the estimate in the direction of cost reduction. If the conversation is about such a construction as a bath, then this task is further simplified.
This object is different from a number of other buildings, first of all, a small weight. And although some wealthy owners of suburban areas prefer to build a "complex", when in the same building, except for the bath, there are laundry, garage, attic floor and a number of other rooms, this is not the rule. Therefore, it will be just about building a foundation for a bath in the usual sense.
A small load created by building on the ground, allows you to choose the type of foundation "ribbon shallow".What does it give?
- Compared with the traditional option, which is laid on the depth of freezing of the soil, this solution allows you to reduce construction costs by a minimum of 2.5 times.
- A shallow base can be arranged on almost any soil. In addition, its design allows you to equip a small basement room. How to use it, a good boss will always come up.
- Taking into account the reduction in the amount of work( first of all, earthwork) the deadline for the complete readiness of the facility is significantly reduced.
Someone can say that it is much simpler and cheaper to install an unfinished foundation under a bath. But this design has a number of limitations in the application. Firstly, it can be mounted for a structure if none of the sections of the bathhouse's foundation are 6 m in length. Secondly, baths are usually made of wood, and this material( as well as a number of others) gives a significant shrinkage.
The unfinished foundation does not have enough "rigidity" and it is likely that in one or more places the tape may burst with time. That is why it is believed that the optimal option for a bath is the bottom shallow.
We will bore the reader with a description of the individual stages of construction, and pay attention only to certain points.
When marking the territory, it is necessary to take into account the requirements that are imposed on the layout of the plots. And in the first place - on the distance of objects from each other, from fences, roads and so on. More information about all this can be found here.
The durability of any structure depends on the correct choice of components, compliance with the preparation and placement of concrete mortar. It is necessary to use the appropriate grade of cement, specify the required type and characteristics of the aggregate, the optimal proportion of ingredients for the preparation of the mixture.
How to mount the foundation
Preparation of the trench
All parameters of the
For a shallow base its depth is approximately 40 - 50 cm( taking into account the elevation above the ground of at least 30 cm).With an average width of 40 to 60 cm, this is quite enough for a bath. These data can be used for preliminary calculation of the required amount of materials( sand, cement, aggregate, reinforcing bar).
The bottom is covered with a so-called "pillow".For this purpose, a smooth layer of coarse-grained sand( of the order of 30 cm) is poured, which is wetted with water for a greater compaction, and then it is compacted by hand. Such a backfill evenly distributes loads arising from soil movements, thereby ensuring the integrity of the entire belt. In fact, such a "cushion" compensates for all mechanical impacts on the foundation even on the pitted soil - read here in detail.
On abrasive soils instead of sand it is desirable to use crushed rock of fine fractions.
And one more thing. Too "high" foundation is not worth doing. Its depth is determined on the basis of the specifics of the site. But how much to raise, is solved arbitrarily. Experienced masters do not recommend making a foundation with a total height of more than half a meter. Such a design loses its "flexibility", which can lead to its destruction if the soil is subjected to high pressure.
Therefore, if you want to "raise" the base( for example, for the basement equipment), it is better to do this by brickwork, rather than by pouring the concrete solution into the higher frame. As an option, the installation of a second reinforced concrete tape, with a preliminary horizontal insulation between them.
Formwork Formwork
As a rule, either low-grade( used) board or plywood sheets are used for this. Based on the construction features, in order to ensure that the geometry of the carcass does not change under the weight of the mortar, elements such as supports, wedges and so on are used.
Reinforcement
Any structure is called reinforced concrete, if it has a metal "skeleton".The concrete itself does not have sufficient strength, so the next step is the installation of the reinforcing cage. How to choose the cross-section of bars, design features, "knitting" elements and installation in place - all this can be learned from the link.
It is worth recalling that the outer rods should not extend to the surface of the foundation( from either side) closer than 5 cm. This is due to the fact that direct contact of the metal with the liquid is avoided. First, the concrete crumbles with time, and the bars can be "bared".Secondly, it is impossible not to take into account the capillary penetration of moisture into the structure of the material( concrete).
Filling the solution
Given the overall height of the tape( and this figure, we determined, approximately 0.6 m), this work is carried out in several stages. It should be understood that the strength of the solidified mass largely depends on the presence of voids( air bubbles) in the structure, and the rate of drying - on the degree of moisture. Therefore, the main task of the master is to "drive" out of the filled solution more air and water.
To make this easier, it is recommended to lay the layers no more than 25 cm, then to produce a mass seal. This can be done with the help of rebar, scrap, shovel - to whom as it is more convenient.
It should be noted that the break between the laying of the next layers should not be large. Otherwise, the solution will firmly "grasp", and between them a kind of "seam" is formed, which will negatively affect the strength. Therefore, all the work on its pouring is desirable to be done in a day. This is not difficult, given the small size of the foundation of the bath.
Further turn of additional measures, which include:
- waterproofing structure;
- insulation( if necessary);
- construction of a perimeter drainage system( if appropriate);
- equipping the blind area.
What to look for
- Soil characteristics.
- Groundwater occurrence.
- Intensity of precipitation in the place of residence, an approximate layer of snow in the winter.
- The presence of a drainage system on the site.
- The material from which the walls are built( and their height), the type of roof. This will determine the approximate load on the foundation.
Accounting for all these factors will allow you to select the optimal dimensions of the foundation and exclude unmotivated financial expenses.
