The process of attaching joists to the foundation
Having completed the installation of the foundation of a house of one type or another, you can begin installing the floors of the first floor. They are based on wooden beams or rounded logs laid horizontally directly on the base of the house. It is possible to do such work with your own hands only after carefully studying all the features of the process.
Floor beams are currently represented by a fairly large list of different products. The simplest option is a timber beam of regular rectangular cross-section, determined based on specific construction conditions.
A more complex type of floor joist, which requires a lengthy manufacturing process, is I-beams with a cross-section in the form of the letter H, placed on one of the sides. They are made from high-quality dried and planed wooden blocks and strips of OSB or high-quality moisture-resistant premium plywood.
The operating principle of I-beams in the form of floor joists involves the distribution of the main forces in the form of bending loads along flat stiffeners. Thanks to this, with a small mass, they are able to withstand very heavy loads. In addition, manufacturing technology and strength make it possible to produce I-beams for openings with a width significantly exceeding the standard 6 meters.
Laying logs on the foundation is carried out according to certain rules, which will be discussed later. Immediately before installing lumber, it is necessary to properly prepare it for further use. You should choose high-quality bars made of oak, aspen or coniferous wood. The main requirements for them are as follows:
Options for attaching joists to the base of the house
An important point is the correct fastening of the logs to the foundation of the house. At the same time, the abundance of base options requires certain installation features for each of them. Let's consider each specific case separately.
A fairly common type is. It is a base up to half a meter wide, raised above the soil by 0.4 - 1 meter. Not all novice builders know how to attach joists to this type of foundation. There are two main ways:
Regardless of the chosen option for laying floor beams, it must be carried out in compliance with a number of mandatory requirements, which should be discussed in more detail.
Before laying logs on the foundation, it is necessary to correctly calculate the required number of beams. They are installed in increments determined based on the expected thickness of the boards used for flooring. Thus, in the case of designing lumber for finishing covering with a section of 20x100, 20x150, the distance at which the logs are installed on the foundation is only 0.3 meters.
Assuming a floor covering made from a standard tongue-and-groove floor board with a thickness of 30-35 mm, the timber installation step can be increased to 0.5-0.6 meters. If you choose 50x150 lumber for the floor, you can safely lay the logs at a distance of 1 meter from each other.
Before laying logs on bricks or wood, it would be a good idea to determine the geometric parameters of the floor beams. For their calculation, the determining value is the width of the overlapped span, that is, the width of the room. So, with a distance from one wall to another of 2 meters, you can use lumber with a section of 110x60, 3 meters - 150x80, 4 meters - 180x100, 5 meters - 150x200, and 6 meters - 180x220 mm.
If the base of the house is manufactured in the form that is recommended, the lags can be attached to the foundation in a way different from those described above, but in compliance with the specified installation parameters. It consists of using dowel nails installed through the timber into pre-drilled holes in the concrete.
The process technology is not complicated and is accessible even to novice builders. To install joists with your own hands on such a concrete floor, you can use a hammer drill or a drill with an impact mechanism. Pre-drill holes in the timber using a wood drill. Then the parts are laid at the installation site and recesses in the concrete of sufficient depth and diameter are made through them.
Fastening joists to a slab base
Dowel-nails with a diameter of at least 12 mm are installed in place and pressed with a half-sledgehammer or a hammer with a striker weighing at least 1 kg flush with the surface of the wooden beams. As a rule, with the correct selection of fastener parameters, installing joists on the foundation in this way ensures high quality of their fastening.
This method is applicable when using logs with a cross-section of at least 150x150 mm. This allows you to lay a sufficient amount of backfill or slab insulation made of mineral wool under the subfloor, since it is impossible to lay the floor on a foundation without high-quality thermal insulation.
When performing work inside a residential building or apartment, the problem of installing joists on a finished concrete floor often arises. This type of work is used if it is necessary to insulate the lower surface of rooms, level it, or lay one or another type of floor covering. In this case, two installation methods can be used.
The first method involves rigidly fixing the bars to the base, which can be done in the same way as fixing the logs to the foundation in the form of a concrete slab. To install the logs in this case, you can use dowel nails or plastic dowels with self-tapping screws of the appropriate length.
Using preliminary markings, or using pre-perforated logs as templates, we drill holes in the floor. Their diameter should allow the fasteners to be tightly installed. Next, we fasten the logs using self-tapping screws or dowel-nails, controlling the horizontalness of the surface of the beams and the overall flatness.
Subsequently, after attaching the logs to the concrete floor with your own hands, you can insulate the base by placing the selected type of insulation in the gap between the bars. Before installation, do not forget to thoroughly treat the wooden parts with antifungal stains and fire retardants, which reduce their flammability.
Wooden floors have been used for many centuries as the main covering for the home; they are also highly environmentally friendly and have a beneficial effect on our health. And laying a wooden floor on joists is possible even for non-professional builders. But in order to lay a wooden floor reliably, you need to know some tricks and features of this process. Below we will look at them in more detail.
But, as a rule, wooden floors are made in a finished version using planed dry boards. In this case, you will not need additional finishing - you will just need to lay the wooden floor.
It is very important to purchase high-quality wood and correctly calculate the amount of material.
You can do this by following simple rules:
Concrete must be cleared of construction debris and all potholes and cracks removed.
Initially, a layer of soil needs to be removed along the entire perimeter of the room, while going deeper below ground level by 20 cm. Next, a layer of crushed stone is poured, and then river sand. 
Each subsequent layer must be moistened with water and compacted. It is also necessary to lay a waterproofing layer to protect the joists and wooden floors from moisture. And after that they immediately begin to install wooden ones.
Laying pipes under the floor Before installation, the logs are treated with a special water-repellent compound and left to dry for several days. The supports for the logs are brick columns, about 40 cm high and 2 bricks wide. They are installed on cement mortar and must be made identical throughout the entire height.
For more accurate control, use a level. There are two outer posts on one lag, and if the board is long, an additional post is placed in the middle.
And the step between adjacent wooden logs is determined by the thickness of the boards being laid, for example:
It is necessary to place the logs perpendicular to the sunlight.
A wooden floor, laid according to all the rules, will serve you for many years and provide a good microclimate throughout the house.
Logs are lathing elements for flooring. They are necessary for the final floor structure to be of high quality: smooth and strong. Strengthening and leveling the floor surface without joists is very problematic. An unreinforced covering will sag under the influence of heavy furniture, and the floor itself will creak and vibrate when walked on it. Floor joists are almost always installed. How is their size selected and installation done?
The main function of the log is to create a flat surface for the following work. But sheathing under the deck also serves other purposes. They promote complete ventilation of the underside of the flooring, which prevents the boards from rotting.
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This function of the timber base is of great importance in those rooms where the floor is laid on the ground and dampness due to groundwater creates serious problems even with a high subfloor.
With the help of joists, a space is formed between the flooring itself and the base of the floor - a kind of buffer that helps improve the soundproofing qualities of the floor. The same space is used for laying a layer of insulation, and, if necessary, utilities.
Installing floor joists allows you to obtain a durable floor even with an uneven base due to support points placed at a certain pitch.
As a base for the flooring, you can use any materials that meet the requirements of strength, evenness and low deformation coefficient under load. These technical characteristics correspond to products made of metal, plastic, reinforced concrete, wood and compounds produced on the basis of synthetic resins. What kind of joists are best to use for the floor? Comparing the cost of all the above materials allows us to identify the favorite - wood. In practice, ordinary wooden beams are used for logs. 
The material for timber is usually coniferous wood. The timber used for floor joists is made from spruce, pine, and fir. But larch is recognized as the best option, since its wood is not only highly durable, but also resistant to rotting.
Spruce and pine are more popular only due to their low cost.
When choosing a material, you can ignore the presence of resin pockets and other minor defects and buy grade 2 or 3 lumber - the functionality of the timber base will not suffer from this.
Beam made of Siberian larch. When choosing logs, you can save on material by replacing larch with spruce, but saving on the moisture content of the beams is not recommended in any case. The moisture content of the timber should not be more than 20%; at higher humidity values, the material will be deformed during the drying process, which will lead to problems with the finished floor.
If you have chosen spruce or pine as the material for the sheathing, then you should take care of waterproofing the beams when laying them. The joists can be laid on different floors; depending on the characteristics of the base, the waterproofing work will also differ. If the beams are mounted on reinforced concrete floor slabs, then you first need to lay a layer of foamed polyethylene. In the case when the logs are attached to brick columns, polyethylene is laid between the soil and the column itself, as well as between the column and the beam. For the layer between brick and wood, roofing felt is suitable instead of polyethylene.
Foamed polypropylene. Floor joists, regardless of the type of wood, are recommended to be treated with an antiseptic before installation. Such precautions are most relevant in wooden private houses, where woodworms can become a big problem for the owner of the house, as they pose a threat to the durability of the entire structure.
The reliability of the entire floor structure depends on how correctly the size of the lag is selected. Before purchasing beams, you should calculate their required length and thickness.
There are usually no problems with the length of the lag: depending on the direction of installation, it should be equal to the length or width of the room where the floor is being made. The best option is the length of the timber 2.5-3 cm less than this distance. This ratio of two values, when the length of the log is slightly less than the length of the room, allows you to avoid deformation of the structure due to temperature changes.
The length of the beam should be 2-3 cm shorter than the width of the room. It is advisable to make floor joists from whole lumber, but this is only possible when the size of the timber matches the parameters of the room. If the length of the bar is not enough, then splicing two elements is used. The work is carried out in half a tree, sometimes using galvanized overlays.
It is not difficult to splice two bars, but in order for the structure to be strong, two rules must be strictly followed:
Failure to comply with these requirements entails the risk of low floor rigidity at the junction of the timber.
Methods for splicing lags. Adjacent floor joists should be spliced with an offset of one meter. This parameter affects the size of the original bars, which should also be taken into account when purchasing them.
If everything is quite simple with the length of the beam, then determining the parameters of the lag section is more difficult. What it is? The cross-section of the log is its thickness, which depends both on the material of the beam and on the design characteristics of the future floor.
The cross-section of the joists for the flooring is calculated based on the maximum possible load on the floor and the size of the spans between the support points of the beams. The generally accepted maximum load value is 300 kg/m2 - this parameter is applicable to residential premises.
When determining the size of the joists based on this load level, the length of the span between adjacent beams is taken into account. How are the distance between floor joists and their thickness related? For this, there is a special table of sizes used by specialists. In the most common cases, the correspondence looks like this: with a span length of 2 m, a beam of 110x60 mm is used, with a span length of 3 m - 150x80 mm, with a span length of 4 m - 180x100 mm. The larger the span, the thicker the timber from which the logs are made should be.
The cross-section of the timber is usually rectangular. In order for the logs to withstand pressure, the rectangular beam is laid “on edge”. This feature of installing the base for the future floor ensures the maximum level of timber rigidity with a minimum volume of lumber.
The thickness of the joists used for flooring may be greater than the specified parameters. Installing logs from timber of greater thickness is not prohibited, and sometimes it is simply necessary.
Sometimes increasing the cross-sectional dimensions of the timber is necessary to lay a thick layer of insulation.
When choosing joists for a new floor, you should also take into account that if you are going to install the floor in a non-residential area, the load on the structure may exceed 300 kg/m2. This parameter will have to be calculated by calculation, and then, based on the data obtained, logs with suitable section parameters will have to be selected.
The size of a metal beam may be smaller than a wooden beam. If you decide to use metal or reinforced concrete beams instead of wooden beams, their thickness may be less. This is explained by the fact that they have a higher resistance to deflection compared to wood.
The size of the joists is determined by the size of the span between them, which in turn depends on the thickness of the board used to lay the wooden floor. Here you should be guided by the following rule: the thicker the flooring, the larger the step you can take. There is a completely logical explanation for this, because the thicker the board, the less susceptible it is to sagging under the influence of gravity.
The ratios are as follows: with a board thickness of 2 cm, you can take steps up to 30 cm, with a thickness of 2.5 cm - up to 40 cm, with a thickness of 3 cm - up to 50 cm. In order to calculate the possible span length for a larger board thickness, you can use the formula: increasing the thickness of the flooring board by 0.5 cm increases the possible length of the joist step by 10 cm. 
If plywood or OSB is used instead of flooring boards, then the calculations are slightly modified. These materials are more rigid in bending, so their thickness is smaller. With a material thickness of 1.5-1.8 cm, you can plan a lag step within 40 cm, with a thickness of 2.2-2.4 cm - within 60 cm.
When using plywood or OSB, sheets of material must be attached to the joists in three places. Floor joists should be positioned so that the fastenings are at the edges of the sheet and in the middle. In this case, the edge of the sheet is not laid across the entire width of the beam, but only up to half.
Wooden logs can be attached to any base, the main thing is to follow the installation rules. To carry out the work of laying sheathing from logs, you will need the beams themselves, a jigsaw, a level, a screwdriver and fasteners. A jigsaw can be replaced with a hand saw. 
Attaching joists to a concrete floor involves the use of various structures, which are divided into simple and adjustable. Adjustable elements have screws in their design, with which you can align the logs.
Special anchors or screws are usually used as fastening. Theoretically, it is possible not to secure the joist bars at all, but then there is a risk of destruction of the floor structure due to the joist moving to the side.
In addition to the tools listed, additional devices may be required. Do-it-yourself installation of floor joists on concrete or soil requires additional fixation using a manual hammer drill.
Adjustable logs. Laying the logs on the ground is done as follows. First, the support pillars are installed. To do this, dig holes about 10 cm deep, fill them with sand and spill them with water for good shrinkage. A plastic film is laid on the sand, on top of which a brick column is erected on the mortar. Its length and width are usually equal to the edge of the brick. The finished columns are covered with roofing felt. Timber is laid on them without fixation, then the logs are hemmed to the walls with galvanized corners.
How to lay logs for the future floor if the base is wooden beams? The order of work depends on how the timber is laid on the beams: across them or along them. If the beam is placed across the beams, then the logs are attached to the beams with ordinary self-tapping screws of suitable length.
In this case, it is important not only to treat the logs with an antiseptic, but also to drill holes, otherwise the risk of the beam splitting will be very high.
If you decide to attach the timber along the beams, then to compensate for the difference in their height, the logs can be attached not only on top, but also hemmed on the sides. Having completed all the work correctly, you will be able to level the floor with minimal loss of room height.
Attaching the joists to the concrete floor is done as follows. If you are installing a floor on the ground floor of a building, then the ceiling should be waterproofed with plastic film. You can use foamed polyethylene with a foil layer. This material will not only waterproof the wood, but also reduce heat loss during further use of the room.
The beam is laid out in accordance with the previously determined lag pitch and set according to the level. To level the base for flooring, pads made of plywood and the bars themselves are used. After this, the logs are fixed to the floor. The best option is to use screwdriver-mounted anchors. There is an alternative way of laying timber on a concrete floor using stands. The stands are attached to the floor slab, and the logs themselves are attached to them with self-tapping screws. 
When preparing to install the floor, it is important to correctly calculate the length and cross-section of the joists, and also think about what distance will need to be laid between the floor joists. If all the parameters are determined correctly, then by using high-quality timber and responsibly carrying out all the work on its installation, your floor will be smooth and beautiful, and will not sag under the weight of furniture or creak when walking.
The service life of both the rough and final coating depends on how well the base for the future floor is prepared. Many new technologies have appeared on the modern construction market, with enormous advantages that provide a lot of opportunities for realizing the most intricate design ideas. But the old, time-tested method, which uses floor joists, is still very popular. In this article we will look at what logs are, why they are so good and how to properly lay a wooden floor on them.
Logs are wooden or polymer blocks of various shapes and sizes located under the finishing coating. The main advantages of using this method:
The logs can be laid both on an earthen foundation and on wooden or reinforced concrete floors of buildings.
Logs are carefully dried wooden blocks that serve as the basis for a finished floor covering.
Wooden floors
If the floors are wooden, then most often their beams are not very even, and when laying joists directly on them it is very difficult to achieve a flat horizontal surface. In this case, the logs should be attached to the sides of the beams.
The main advantage of this method is that you do not need to use pads to adjust the height of the joists. Fastening is carried out using partial screws, and their length must be at least 2.5 times longer than the width of the log, and their diameter must be at least 6 mm.
Tip: to avoid splitting the wood, before fastening it is recommended to drill a hole in the joists and beams with a diameter 2.5 mm less than the diameter of the screw.
If the beams are located at a large distance from each other, then it is necessary to lay the second syllable of the log perpendicular to the first, but at a closer distance. Another way to remedy this situation is to use thicker finishing boards.
Concrete floors
When laying joists on concrete floors, you need to take into account that in such a situation the entire floor structure will look a little different:
For logs, you should not take boards shorter than two meters. If the selected length is still not enough, then the parts are joined end to end.
Important: when connecting lags to each other, you must ensure that the joints in adjacent rows are offset by at least half a meter relative to each other.
The logs are laid on the floor screed. If this is not possible, then the surface of the base must at least have waterproofing.
Before laying the logs, concrete floors must be waterproofed so that the wood does not attract moisture.
But it is categorically not recommended to lay lags on soft insulation; in this case, they will float, which will lead to the gradual destruction of the final finish. If heat and sound insulation allows installation with sheets of a certain width, then the logs on the base are positioned in such a way that the insulating material is located strictly between them.
Advice: if it is not possible to arrange the logs to fit the width of the roll insulation, then you should select such a distance between the logs so that the last cells can be filled with scraps with minimal waste of material.
Laying logs on an earthen base
If the floor on joists is located directly on the ground, then you first need to remove all the turf, scatter approximately 50 mm of gravel over the surface, compact it thoroughly and fill it with a five-centimeter layer of lean concrete. Next, we proceed as with a concrete base, that is, we put waterproofing, insulation and screed.
Tip: when laying the floor on an earthen base, the thermal insulation layer and screed can be replaced with polystyrene concrete.
A little higher we touched on the concept of “distance between lags”. I think many will be interested in how to correctly calculate this value, because in order to achieve optimal load distribution, the logs must be laid at the most equal distance from each other. Usually the distance between them ranges from 350-400 cm.
Let's assume that the room in which the floor joists are being installed has a length of 8.5 meters. The door is in one of the short walls, and the window opposite it is in the far wall. We will place the logs perpendicular to the long side, and the finishing board at a right angle to the logs. This is done so that the finishing coating is located parallel to the light rays entering the room from the window.
Let the width of the bars we prepared for the logs be 0.09 m. Typically, the first and last logs must be 30 mm away from the walls. Let's take the number of lags as y, then their total width will be equal to 0.09*y. The average distance between the logs is 0.375 m and there will be y-1 such distances, then the total distance between all the bars will be 0.375 * (y-1). Knowing the recommended distance to the walls, 0.03*5=0.15, we obtain the equation:
0.15+0.375(y-1)+0.09y=8.5,
solving which we determine that we will need 18.96 lag. Since their number must be a whole number, we round to the nearest value. That is, for this room we need 19 logs. Now we find the sum of all distances between the lags:
8,5-(19*0,09)-0,06=6,73,
and since there are 19-1=18 such distances, we get the exact width between the joists
6.73/18=0.374, not 0.375 as we first assumed.
After laying, the surface of the lag is checked using the rule (long level)
New technologies have also affected such an old method as installing floors using joists. Modern beams already have ready-made threaded holes, adding reliability to the connections.
The height of the adjustable joists is changed by rotating special bolts
In addition, such logs can be adjusted by rotating special bolts, allowing you to quickly and effortlessly change their height. After completing the adjustment, the excess bolts are simply cut off.
Experience shows that wood is an almost ideal material for flooring.
A properly laid wooden floor has a long service life, it is beautiful, environmentally friendly and does not require complex maintenance. Let's consider the main advantages of such a foundation:
If you use coniferous wood when laying the floor, the result will not only be a beautiful and durable coating, but also a wonderful healthy microclimate in the house. So,
What is needed to lay a wooden floor on joists?
The logs are laid at a pre-calculated distance from each other on soundproofing material. When laying, it is necessary to use a level to ensure that the surface is even. The logs are attached to the concrete base with anchor bolts, and to all others - with dowels.
Tip: calculate the length of the anchor bolt by adding 6 cm to the height of the log.
In the gaps formed by adjacent joists, thermal insulation is laid, for example, expanded polystyrene, isospan or basalt fiber. It is more convenient to use roll insulation. Expanded clay can also be used as a heat-insulating layer.
Insulation is laid on top of the waterproofing between the joists.
The installation of a wooden floor along the joists begins from the corner of the room. We place the first row of boards with a tongue and groove against the wall, leaving a small gap between the wall and the boards of up to 10 mm, necessary to compensate for the deformation of the wood as a result of changes in the environment.
The next row is laid offset relative to the previous one by approximately two logs. A tight fit of the boards to each other is achieved by lightly tapping with a hammer on a piece of wood attached to the end of the adjacent board.
The boards are laid in such a way that each subsequent row is offset by approximately two joists
When attaching boards along the walls, it is allowed to place the screws on top, since their heads will still be masked by the baseboard, but in all subsequent rows the covering should be attached only to the bottom wall of the groove, driving the screw heads inside the board.
After laying all the boards, you can begin to close the expansion joints using plinths. In addition, this will protect the walls from contamination.
Tip: for greater reliability, before fastening the boards with nails, it is better to tighten the boards together with construction staples using a stapler.
The base of the floor in old houses is almost never smooth and even. Differences in its height can reach 20 cm and it is very difficult to adjust such a surface. But the use of concrete screed is not always permissible, since not all beams in old housing are able to withstand heavy loads. This is where the use of adjustable joists will help. Let's take a closer look at the installation process:
But laying the floor on joists is far from the end of the floor installation. Next you need to get rid of roughness and altitude differences. To do this, it is convenient to use a small grinding or sanding machine. We begin sanding with coarse sandpaper, which quickly removes all irregularities, and then polish the surface with fine-grained sandpaper.
First you need to determine the places where the floor wobbles and sag greatly. Now here you need to remove the loose nails and screw the screws in their place. Using old nails, you can easily determine the location of the joists under the finished base; these are the places that should be reinforced with additional self-tapping screws so that the head completely fits into the wood. After eliminating the squeak, all these places are puttied, and the floor covering is completely renewed.
We hope that our article will help you decide on the type of flooring and handle the wood flooring yourself.
The vast majority of floors in both private and apartment buildings are made of wood. The support for a multi-layer, pie-like wood structure is most often logs. Logs are long bars made of wood (less often metal and reinforced concrete) laid transversely to the finishing flooring, serving as its solid foundation. This structure is installed both on a monolithic concrete floor and on supporting posts and beams. Installing floors on wooden joists is very profitable due to the relatively low price of materials and ease of installation.
Logs installed as a support on a wooden floor are very functional. In addition to their direct responsibilities, they also:
In addition, individual joist bars can be easily replaced if necessary, without spending money on large-scale renovations in the house.
The installation of a finished wooden floor on joists is somewhat reminiscent of a multi-layer cake, in which it is necessary to lay boards, joists, a waterproofing layer, insulation, and a finishing floor covering over the floor in layers.
Installing a floor on joists involves laying waterproofing and insulation Moreover, regardless of the type of flooring, the insulated floor pie includes additional elements:
This design of floors on joists is relevant for the first floors of private houses. All subsequent floors do not need such serious insulation; installation of a waterproofing layer of the pie in this case is only necessary in direct contact with concrete and brick.
It is necessary to insulate the floors of the first floors and concrete or brick foundations Logs can be purchased at the store, or you can make them yourself. The second option will be relatively cheaper. Wood with a moisture content of no more than 15-17%, 2nd or 3rd grade, is best suited for these purposes. Logs can be made from pine, fir, spruce, aspen and larch.
If you make the logs yourself, keep in mind that the cross-section of the beam should be rectangular. The height is approximately twice the width. The required size is determined based on the parameters of the room, to be more precise: based on the exact distance between the links of the timber frame.
The size of the bars depends on the distance between the strapping links In addition, it is necessary to take into account the thickness of the insulating layer and the size of the spans. In the illustration you can see approximate calculations with laying lags at a distance of 70 cm from each other.
If your room has an intermediate size between the indicated values, you should take a larger value as a basis. This way you will have a certain supply of material, which will allow you to lay it without gaps and make the structure more durable.
To make a wooden floor with your own hands, you can use both edged and tongue-and-groove boards. The second option is much preferable, because its design involves a groove and a tenon, therefore, installing a fine finishing coating is no longer so relevant.
It is preferable to use tongue and groove boards due to the tongue-and-groove system You can use floorboards made of cedar, larch, spruce, aspen and pine. The most expensive and durable materials are solid oak and pine: provided that the installation is carried out correctly, they will last for several decades. In turn, larch is excellent for rooms with high humidity, because it is not susceptible to rotting, and healthy aspen and alder boards are great for sleeping areas.
Oak and pine boards will last a long time If you purchase first-grade floorboards, you don’t have to spend money on the final flooring, and at the final stage simply sand the boards and varnish them.
The main thing is that before laying, be sure to treat the boards with antiseptic antifungal preparations and impregnate them with a water-repellent composition.
If you are installing a wooden floor with your own hands, be careful when choosing wood: the boards should be dry, but not overdried. Wet wood, after drying and under the pressure of furniture, can become deformed. Always buy boards with a margin of 15-20% in case of need for trimming, errors and defects.
When you install a floor on logs, use the rule: the thicker the floor board, the wider the installation and the farther apart the logs are located.
For example, for a board whose size is 5 cm, you can make a step (the distance between the lags) of one and a half meters.
If you use thin boards, you can take small steps so that the board does not sag. The most common step length between joists is 50-70 cm.
The distance between the lags is most often 50-70 cm Also keep in mind that you will need additional space to make it convenient to lay the insulation inside. If the size of the base does not correspond to the values in the table, then it is calculated upward.
When installing logs yourself, you should strictly follow the following rules:
Wood is a flooring proven by time and centuries of experience. When laid correctly, it can serve for decades without losing its visual appeal. In addition, this is the most environmentally friendly, “breathable” floor, guaranteeing a high degree of heat and sound insulation of the premises of both a private and apartment building.
Wooden floor construction with joists To make laying a wooden floor on joists quick and comfortable, you will need the following tools: level, hammer drill, saw and axe, hammer, nail puller, drill, screwdriver and keys. And also the following materials: floorboards (sometimes the role of the subfloor is given to plywood boards), logs, insulating material, fasteners (anchor bolts, screws and nails).
If all the necessary materials for installation are available, you can begin laying the logs on top of the soundproofing material. As already mentioned, the surface must be leveled, checking its horizontalness with a building level. The boards are attached to the joists using dowels.
Now it’s worth taking a closer look at the entire technology of installing floors on joists in a private house.
The first step is marking the work area and preparing the base. First, you should compact the soil and secure the formwork with ten-centimeter sides. A reinforced mesh is placed at the bottom and then the concrete mixture is poured. You need to wait a couple of days for the concrete to dry. After this, a waterproofing polyethylene film is laid on top of the concrete floor, and then supporting structures are constructed.
If the floor is cold, the space that remains under it after its construction must be filled with sand or expanded clay (do not fill it to the top, you need to leave about 5 cm of free space).
You can insulate the floor using expanded clay The second step will be to ensure normal ventilation of the space under the floors. For these purposes, small holes are made along the perimeter of the plinth (for every 15 sq.m.), which, in order to prevent mice from entering the house, are covered with a non-ferrous metal mesh.
The next step is insulating the floor. Expanded polystyrene, isospan or thermal insulation roll material are perfect for these purposes. This material is laid on a waterproofing layer of isolon, which is attached to the joists in advance using an industrial stapler.
After laying the insulation, you can begin laying the plank covering over the joists.. Installation must begin from the corner of the room. The boards are screwed directly to the joists using self-tapping screws.
Scheme of a wooden floor If the boards are processed and well sanded, they can play the role of finishing, finishing flooring. If a layer of finishing coating is expected (laminate, parquet, linoleum, etc.), you can begin laying it immediately after finishing the work with attaching the boards to the joists.
Thus, installing a floor on wooden joists has many advantages over laying the floor directly on top of a concrete or soil floor. In addition to the fact that it smoothes out all the unevenness of the floors and distributes the load evenly, it also perfectly insulates the home and promotes sound absorption.
