How to avoid dampness under the floors in your home. Wooden floor on joists on the first floor of a private house How to cover the soil under the house
As the famous Ranevskaya liked to repeat, “the weaker sex are rotten boards.” Yes, the situation is actually one of the worst pleasant - a wooden floor has served you faithfully for decades, and at some point they begin to resemble ship planks: in some places they wobble, in others they bend, and in others they even break through... Going through the floor is as easy as shelling pears. But, even if you buy expensive and water-resistant wood, install more solid waterproofing and even hang a hygrometer - this will not save you from repeating the same situation in a few years if you make the same mistakes again during the arrangement. Therefore, let's learn how to solve such problems even before such labor-intensive repairs begin.
First, look at what happens if you don’t do everything wisely in time:
Let’s make a “diagnosis”: why did the floor turn to dust?
But let’s first learn how to “diagnose” rotten floors. So:
- The boards have turned to dust, but you don’t feel any obvious moisture? And does the wood look clean? This is not a rotten floor, but a floor that has been eaten by bark beetles. How to deal with them is in another section of our site.
- The boards are rotten, no moisture is felt, but there is some kind of plaque and something like white foam on the boards themselves? This is a fungus that does not always appear due to dampness; rather, it is introduced with already diseased boards.
- Do the boards turn to dust and even turn black in places? This is a sure sign that your floor is rotting, and it is rotting because of water. And water can get to it in a variety of ways, and this is not necessarily just groundwater from the basement. Everything here is much more complicated, and now we will gradually figure it all out.
- Are the boards rotten and the insulation soaked in water? Well, if moisture comes from the house (for example, the walls are to blame), then this will be noticeable first of all by the wet insulation. In this case, you need to work with the house - at least for the first time by installing a modern dehumidifier.
Have you determined what happened to the boards? Go ahead.
All about the rotting process of wooden floors
The source of rot for any wooden floor is water. Constant access of moisture and air to this material has a detrimental effect on it, especially frequent wet-dry cycles.
To determine the exact cause of rotting floors in the house, you should note the following factors:
- History of construction. What and from what, whether the blocks were dry, for example, how the foundation was waterproofed and what the roof was covered with.
- Weather. How often does it rain, and is there slush?
- Age of the house.
- How is air exchange organized? Eg, In order for the vents to work correctly, the diameter of each of them must be at least 25 cm.
- Were all standards observed when installing the floors?
The first signs of the beginning of floor rot are the swelling of the boards and “playing”. Already at this stage, the floors can be saved - without completely re-laying.
The most common sources of moisture in the underground are rising damp currents from the ground (especially if groundwater is located high) and too wet air from street ventilation. How to understand what exactly you have? Do this simple test:
- Close all vents well.
- Open a hatch in the underground or create a small hole near the wall to establish air communication between the room and the underground space.
- Place heaters in the underground so that the air temperature there becomes the same as in the room. Those. align it.
Now check whether the air in the underground remains as humid - if so, then the source is moisture from the soil. You can isolate it modern materials, laying them on the ground and covering the foundation from moisture. We also note that many of the types of oils that are coated with floorboards before installation also contribute to wood rotting.
The most common causes and solution to the problem
Let's look at the most common options that cause the floor to rot:
Option #1. The products don't do their job
There are too few vents in the house, up to 6, and they are located low to the ground. This makes airflow almost impossible and the environment becomes too humid over time. The joists and floors are rotting.
What to do: instead of insulation in the floor pie, lay a moisture-proof membrane that will control the movement of water. Next, organize a ventilation gap using counter slats across the beams. There should be a gap and ventilation slots on the ventilated baseboard. This will dry out any possible moisture. And, if the vents are not working enough, there should be some other ventilation under the floor. Usually this is a metal corner in the floor with holes - that's enough.
Option #2. The ground is too close
The wooden floor is laid on logs, and underneath there is earth, at a distance of up to 20 cm. Such a floor will deteriorate very quickly. And it’s precisely these kind of constructions that would-be builders often make in private homes – quickly and angrily, as they say. Sometimes, however, instead of earth you can find wet clay there, and the result is the same.
What to do: definitely redo the floor: waterproof it into a pie, raise the floor itself higher to regulate moisture, and protect it well from dampness. Another option is to put geofabric on this soil, and sand with good compaction on it. It will not conduct water upward, even if there were no geofabric (this is prevention) - just like the sand on the seashore is dry, but if you dig deeper, it is wet.
Here's an example close location the joist to the ground, and during the process of replacing the floor they were raised:
Option #3. Hopelessly damp basement
It will be difficult to remove moisture from it, and it will still (even with good ventilation) reach the floor boards. High groundwater is especially dangerous for floors.
What to do: in this case, it is better to abandon it completely, foam the air and completely fill it with clean river sand. Water each layer generously and compact it well. Lay plastic film and insulation on top of the sand cushion, then plywood, and then the floor itself. And, most importantly, remove the water as much as possible from the house itself - using external drainage. Usually even pipes around the house are enough, but sometimes people build small storage tanks nearby groundwater – deep holes. It’s not even difficult to pump water out of there.
Option number 4. Vapor barrier installed incorrectly
It often happens that specific material it is laid the way the floor was designed, and then the boards suddenly rot. This happens because the person laying the floor did not study the instructions for the vapor barrier itself - different manufacturers for its installation the most different requirements. So, materials of one brand should fit tightly to the insulation, while others should have a ventilation gap between them.
What to do: When changing the floor, you can use the same insulating material, but this time study thoroughly all the information about it. You can take a closer look at everything in this section of our website. And keep in mind that a vapor barrier can be done on the underside of the floor pie when the underground itself does not differ in temperature from the room. But if it is cold, then only the soil itself can be waterproofed, and good ventilation will need to be provided above.
In this photo instruction, the rotten floor in the bathhouse was due to incorrect application of the membrane, and now it has been completely replaced:
Option #5. Always wet insulation
The insulation gets wet, causing the joists and floor boards in contact with it to begin to rot.
What to do: remove the vapor barrier from the bottom of the insulation and attach a membrane in its place. If this does not help, remove this insulation altogether, and instead insulate the base and blind area, completely plugging all vents. There will be no more heat loss, and the problem will be completely solved. And the very first thing to do is determine where the floorboards began to pick up moisture. So, it can come from underground, or from the house itself.
Look at the example of how a rotten floor was replaced and its pie was correctly arranged:
Option number 6. There is a real swamp under the house
For example, today they are actively selling plots with a former swamp for private development. And problems with the floor – already in the first few years. No matter what you cover the floor with, moisture still gets to the boards, and they rot over time. There is only one way out: good vapor barrier from below.
What to do: arrange a special drainage with a separate pump under the floor, and another one - external, without a pump, just with water drainage. The problem will be solved.
A hole for targeted drainage of water in the base of the foundation can be made as follows: either using a reinforced concrete screed with a slope, or simply laying roofing material with an overlap along the edges. In addition, if your underground is damp, under no circumstances should you put laminate or linoleum on a wooden floor. They simply will not allow moisture to pass through, and the floors will begin to rot. When laying a new floor instead of a rotten old one, be sure to treat the boards with an antiseptic at least twice.
Here's how to protect such a floor - this one also rotted from the swamp under the house:
Option No. 7. The floors were insulated too hard
Yes, all the warmth remains in the house, but under the floor will now freeze so much in cold weather that it will thaw all summer - and until the fall. Result: a huge amount of moisture.
What to do: review the insulation design and simplify it a little.
Option No. 8. Excessively humid air inside the house
Let's explain in more detail. If ventilation, namely the exchange of the walls of the house with external environment If it is arranged incorrectly, then in the warm season this is not yet felt. But at the very first fire, internal vaporization increases significantly (moisture is released from the walls and ceiling), warm air goes up, as we know from physics, cold goes down. And condensation forms on the floorboards, and precisely in the coldest place - on the insulation. Pay attention: do your walls get wet where external moisture could not get in? And for accuracy, buy a regular hygrometer and measure the humidity of the air inside the house in winter.
Another clear sign that the air in the house is currently very humid is frost on the walls during the first kindling.
What to do: if the phenomenon is temporary, then open two windows in the house, close the vents, and in this way expel the humid air to the street.
Option number 9. From old age
It happens that the floors rot even in a very old house. This is the property of wood.
What to do: just replace it. Just be careful when using the jack - if the house is made of wood. And carefully examine the logs - if possible, they should also be replaced.
This is what a competent complete replacement of a wooden floor due to rotting due to old age looks like:
Option No. 10. No ventilation gap between the floor and the wall
Those. the floors are made close to the walls, which in itself is a violation of all technologies. This design is especially vulnerable in wooden house– will be the first to begin to rot lower crowns, and then the floor itself. The log house itself will not last long without intervention either.
What to do: completely change the floor plan and throw away the rotten boards (not all of them could have gone bad). It is advisable to replace everything with a good concrete floor, especially if we're talking about about the bathhouse. So, for a Russian steam room, use the following floor pie:
- Sand pillow.
- Crushed stone.
- The screed is 3 cm thick.
- Waterproofing film.
- EPPS.
- The same film.
- Reinforced screed 10 cm thick.
Why film? It is needed both below and above, because there will be a washing room or steam room above the floor, and this is especially wet areas. Secondly, it will not let cement laitance into the insulation during the process of pouring the screed.
Option No. 11. Only the beams rotted
If you find that only the beams are rotting and the floor is not touched, most likely the foundation freezes heavily during the cold season, and condensation accumulates on it from the inside. Beams are the first to be distributed, of course.
What to do: here it is necessary to dismantle the old beams. Next, where the boards come into contact with the base of the foundation or the walls of the house, waterproof them with rubemast or glass insulation in several layers.
Using a geomembrane as waterproofing under the floor should generally be done during construction, as an axiom. Glue its edges to the foundation with double-sided bitumen tape, and forget about underground dampness. If you also change the joists, make them with a slight slope to the side - so that the condensation that appears no longer lingers on them, but flows down. And for this water to escape, it is also advisable to make a drain under the foundation.
Option No. 12. The floors are rotten in the apartment
This is a sure sign that they lack ventilation.
What to do: organizing the necessary holes is not difficult - you need one under the battery and one on the opposite side.
Products: necessity or evil?
By the way, in Lately The underground is increasingly being built without ventilation. Thus, the masters call this “a Russian tradition - first driving humid air underground, and then actively expelling it from there.” Therefore, today, more and more often, the foundation and floor are simply well insulated - and that’s all. This way the floor will never rot. What does this design solve?
Let's take a closer look at this point. For example, in the spring the air outside is much warmer than underground, and besides, it is also humid (the snow is melting). And this warm and moisture-saturated air penetrates through the vents under your floor and immediately settles in the form of condensation on the cold boards. And they spend a lot of time in this dampness - until the summer. Is it any wonder that wooden floors completely rot within a few years? And through the same vents, rodents sneak into the house in hordes in the fall. That is why today others are actively used Constructive decisions, and ventilation is carried out in a slightly different way - through the house itself.
Such an underground is called closed air-conditioned, i.e. mechanically ventilated. The fact of the matter is that if the temperature of the underground and the room does not differ much, then condensation on the floorboards will not occur. On the other hand, if your underground is and will be ventilated with vents, the movement of air from it through the floor must then be completely blocked.
These are the solutions to this problem - everything is actually very simple.
Good afternoon We built a house from 150/150 timber, the size of the house is 9/10. The foundation is strip, the height from the ground is 75 cm. There is just dirt under the house. I want to cover it with expanded clay, but I don’t know how to do it correctly, and is expanded clay needed under the house at all?
Oleg, Moscow.
Hello, Oleg from Moscow!
If you have nowhere to put the money, then you can fill the ground under the log house with expanded clay. But this is tantamount to heating the street with a fire made of bucks, but do you need it?
Let's think theoretically. You want the floors in your house to be cool. Cold from below the floor can come in two main directions - from the ground and from the foundation base.
Since your address is Moscow (or the surrounding areas, and not the Arctic, where there is permafrost), the cold from the surface of the earth is minimal. And from the side of the foundation plinth - maximum. Hence the conclusion - it is not the ground of the underground space that should be insulated, but strip foundation.
In old houses and village houses they did and still do the so-called zavalinki. That is, around the entire house along its perimeter, earth is poured at a distance of up to half a meter from its walls. And up to the height of the second crown of the log house. Alternatively, a box was made or poles were driven in, and between it and the base of the hut, instead of earth, there could be peat, turf, straw, reeds, sawdust, etc. Boards were laid on top, on which the residents of the house and their neighbors whiled away their time in the evenings. And the rest of the time, the boards served as a drainage system for rain running down from the roof and away from the walls.
Nowadays, piles are rare, and they prefer to insulate the basement in a slightly different way - from inside the underground.
If I were making a house for myself, I would do in the following way. First of all, sand was poured over the entire underground area in a layer of 5 - 10 centimeters. Then, glass insulation was laid in one layer, with each row of sheets overlapping 5 centimeters. This will achieve the cutoff of soil moisture from the underground space.
After which, along the entire perimeter of the base, the height of those 75 centimeters that you are talking about, the concrete walls are impregnated (coated) bitumen mastic/sold in tin cans/. To increase the fluidity of the mastic, it is diluted with gasoline and mixed thoroughly. The base is covered with rollers or a kvoch (a sponge on a stick).
Then formwork is constructed from antiseptic stakes and boards, which are installed at a distance of 15 - 20 centimeters from the base inside the underground. The space between the base and the formwork is filled with expanded clay. All. Warm, dry.
Instead of expanded clay, penoplex slabs 5 centimeters thick can be used. Their standard size 0.6/1.2 meters. They are fastened with dowels with a wide round plastic head. Using a hammer drill to drill holes in concrete for dowels. The cost of one slab is a little more than one and a half hundred rubles.
The foundation base must have at least 2 ventilation holes per wall. And with a diameter of 100, or better yet 150 millimeters, protected from rodents by bars. IN summer period the ventilation holes are open, and in the winter they are closed (or plugged). You can use foam rubber 100 millimeters thick (the closure is made of a sheet or sponge).
That is, in the summer the space under the floor is ventilated, but in the winter it does not cool down.
If you have already closed the underground and it is difficult to penetrate there to carry out these activities, then use your wits. Either insulate the base from the outside, or make a hatch in the floor. In short, show elements of fantasy.
Well, if anyone recommends more practical options, then don’t dismiss them either.
Ask a question to Semenych (author of materials)
Our website is regularly updated with interesting and unique materials and articles on the subject of lumber, building materials and works, the author’s opinion and knowledge of a real coven with more than 15 years of experience are given. There is a section - funny stories shabashnikov. If you would like to receive information about this, subscribe to our website's newsletter. We guarantee that your address will not be shared with third parties.
Initially, the soil in its own way physical properties under the floor of any building is a constant source of moisture. With slight deepening it is dry appearance the underground soil “opens up” moisture and bad smell rotten. All the negative impacts caused to structures and people from a damp underground will not be described in this article. Let's look at how you can deal with moisture under the floors of buildings.
What are the sources of excess dampness and moisture?
The first way
In the absence of a good blind area (cement-sand mixture, asphalt concrete mixture with hot bitumen), water from the roof of the structure will certainly begin to accumulate under the floor through foundation cracks.
The height of water rise through capillaries (cracks in foundations) is from 300 mm to 500 mm, which forces vertical insulation (a layer of roofing material is glued with hot mastic to the wall of the house and to cement screed before laying the outer part of the blind area, at an angle of 90 degrees). Later you will finish the plinth decorative materials, and the roofing material will remain inside, as your insurance against external water.
The second way
Groundwater is located high. Especially in the autumn and spring periods. The movement of water will be along the path of least resistance, namely under your floor. The solution is additional drainage (see below).
Properly carried out drainage work, along with joint landscaping storm system, are guaranteed to ensure the absence of moisture not only in the underground and in the house, but also in the adjacent territory, which in turn has a beneficial effect on the lawn, shrubs and trees.
The third way
Warm and humid air penetrates through the vents into the underground. On cold walls it condenses and settles in the form of dew.
In a dysfunctional underground, humidity can reach 80 percent. However, humidity up to 50 percent is considered normal, and 30-50 percent is ideal.
The problem of damp underground is solved as follows
First way
Sealing foundation walls with inside. Additional high-quality concreting followed by gluing the walls and floor of the underground with polyethylene reinforced film. The main difficulty in performing such work is sealing the film joints until they are airtight, especially in the corners. It is necessary to use special sealants and mastics. The film is secured to the top of the wall using plastic dowels.
To protect against mechanical damage An additional layer of concrete is placed on top of the film. Of course, doing this on the floor is easy, but you will have to tinker when placing the film on the walls. It is possible that concrete will not hold up over a large area of walls, in which case they are covered with bricks in one row or protected with plastic sheets.
Second way
Creating effective ventilation. If supply and exhaust ventilation does not cope with its functions, a forced one is installed.
However, it is still desirable for natural supply and exhaust ventilation to work.
An influx will flow through the vents fresh air, and exit through a pipe of quite impressive diameter (up to 0.5 m). Moreover, the bottom of the pipe, which acts as an exhaust hood, should start almost from the bottom of the underground, thus, the cold air located below will tend to rise.
Under bottom part exhaust pipe, you can place a lit candle under the exhaust pipe for a while. Warmth, created by candles, will be enough to speed up air exchange by creating additional draft. Thus, the underground can be dried relatively quickly.
Third way
Performing groundwater drainage. To perform such foundation drainage, grooves are made along the perimeter of the underground foundation at a slope towards one of the corners of the building. Water through a pipe from this corner enters a sealed drainage well located outside the house. From time to time, water from the well will have to be pumped out.
Fourth method
Option at your discretion. During the cold season, close the vents with foam plastic plugs.
The fact is that warm outside air can contain much more moisture than cold air.
As a result, it creates additional dampness due to condensation on the underground walls.
Flaws this method: what to do in case of sudden temperature changes?
In the underground, as a result of the lack of ventilation, the processes of mold formation and rotting can be significantly activated. However, this method is worth a try because it is very easy to implement.
Fifth method
The easiest, but quite effective method eliminating dampness in places where it is impossible to reach - cover the ground under the floor of the building with one of the waterproofing materials: plastic film, roofing felt, etc. However, it is better to do this during the construction period, before starting the subfloor. Or tear up and re-lay the floors. Moisture will not be able to rise up from the ground, which means it will not penetrate through the waterproofing material. Press down the film in several places. So that the film cannot move for any reason (omnipresent moles, drafts through vents, etc.).
It should be noted that there are other methods of dealing with dampness in the underground. We hope the options described will give you some ideas and help you solve the problems of dealing with high humidity under the floor of your home!
IN general design The extension was such that everything was done on metal posts dug in and concreted with spots in the ground. The frame and the walls themselves were attached to these columns, but there was no foundation as such. The floor used to lie there on parole - somewhere there were pieces of iron, somewhere there were pebbles, bricks were placed under the joists. More precisely, there weren’t even logs there, but they were cobbled together from what was there - somewhere a healthy beam, somewhere a wide board, somewhere completely empty and everything fell through. In general, everything has rotted for a long time and is being dismantled quietly. As it was, I don’t want to do it anyway. I haven’t decided yet which one is correct.
In general, there were two long rails and a pipe as supports. The plan is not just to lay them on the ground, but to place them on brick pillars or small areas filled with concrete. And then these platforms are somehow adjusted in height to one level by laying bricks or pieces of wood of the required thickness.
Lay these rails parallel to them, and then lay the logs across them.
Only at first I found on one site that for the floor you need timber 150 by 100, preferably, and then boards for it. And I planned to lay these bars in 1 meter increments
On another site yesterday I read about laying a plywood floor. And they write there that optimal size log 40 by 100 mm. And they are placed in increments of 40-50 cm.
Well, 40 cm may be too thick, but now I’m thinking about this option, to take thinner bars like theirs, and place them more often, in increments of 50 cm.
But they lay their floors on concrete slab. And there is support over almost the entire surface of the floor, and I have only three points - the ends of the beams on the rails, and a 4-meter round pipe in the middle, as a third point, so that the logs do not sag too much. Will such a section be enough for me, given that the distance between the points will be a little more than 2 meters?
Or don’t bother with these rails and make more columns?
How did who do it?
And the second question, since there is bare ground there, and the wind is whistling, blowing everything through, we need to somehow waterproof it.
In general, now I decided to start by pouring a small strip of “foundation” already under existing walls. It’s not very deep there down to the sand - about 20-30 centimeters deep - it’s easy to remove the layer of earth down to the sand, and cast such a narrow strip - about only 10-15 cm wide - right under the wall, so that rainwater from the street, from the roof, does not flow under the house, under this floor. And then I’ll start to think something inside. Maybe the roofing felt should be laid on the ground? Or will it be dry anyway if the cracks from the street are closed on all sides with this tape?
I need the cheapest one economical option, but also so that you don’t have to redo it in 5-10 years, and don’t regret that everything is already screwed in, the partitions are there, and you need to dismantle the floor of the house in order to redo these floors.
it blows everything away
most cheap option- lay foundation blocks and make a floor on them
think about it, if there is air exchange under the floor, is it necessary to do anything there at all....
but if you cover the vents with tape, don’t forget to make ventilation holes
the cheapest option is to lay foundation blocks and build a floor on them
Therefore, I am inclined to the option of casting these platforms on site. It will be the same concrete. I'll somehow be able to handle it with a shovel. Before this I filled in small volumes.
Well, foundation blocks are both expensive and very heavy. Here you either need equipment, or 10 healthy men who will help move them. And with delivery too headache. And no one there will really help me. Either one person will do everything, or a brother will come up with something heavy for a day at most and help drag it.
Therefore, I am inclined to the option of casting these platforms on site. It will be the same concrete. I'll somehow be able to handle it with a shovel. Before this I filled in small volumes.
you're not thinking about that)))
a 20*20*40 block weighs about 30 kg.
you're not thinking about that)))
a 20*20*40 block weighs about 30 kg.
And I don’t know what thickness of reinforcement to use either. I'll probably take 8 mm.
Well, if they are like that... We need to see how much they cost on average. And then I still have to cover up the joints between them. Water will flow through these joints 100 percent, and then this design will be of little use. It won't save you from the frost, only from the wind?
And the earth also has this property - it moves when it freezes and unfreezes. I think that these blocks, without their reinforcement, will rise and fall on their own. The result will be trouble, not a foundation.
I want to take long reinforcement along the length of the entire wall of the house, and put two rods of them into this strip. This way, at least she will walk entirely, and not in parts. Although I really want two rods, how many are needed, I don’t know for sure. Maybe one is enough there.
And I don’t know what thickness of reinforcement to use either. I'll probably take 8 mm.
seal the base with a flat shiver
They probably cost 50-60 rubles per piece.
I meant to use these blocks as linings for the joists, and not to lay down tape from them...
under the blocks it is natural to pre-prepare the place - remove the soil, and make a sand and gravel cushion, roofing felt on the block, and logs on the roofing felt
seal the base with a flat shiver
And with what step are the logs themselves laid?
Understood. There will be crushed stone anyway, there is sand there. We need to see how much they cost. So you can stick it in like a column, put it on the end? Or are they placed horizontally?
Well, this is not the biggest problem - I can’t find these blocks - they can be cast on site. But at what distance should we place them? If, as I planned, at the beginning, at the end of the room and in the middle, then the distance between the supports will be 4.7 in half = 2.35 meters. This is fine? Or do we need to install more of them? What cross-section should the beam be at such a distance so that it doesn’t break, and I don’t need a large supply - I don’t plan to keep elephants there. The maximum will be big heavy cabinets with all sorts of junk, a sofa. The internal partitions will also be hanging on supports, that is, they will not be tied to the floor.
And with what step are the logs themselves laid?
but this depends primarily on what the floor will be made of and what load will be on it...
Well, you didn’t write the floor area))
I am a supporter of using lag 50*150 every 60-70 cm.
but this depends primarily on what the floor will be made of and what load will be on it...
It’s just that ideally I would make two fulcrum points and that’s it. The middle columns, after all, can also rise and fall over time from winter to summer, and the floor will either sag or bulge into a hump. Or simply the log will not rest on all points.
50 to 150... And as I understand it, they are placed edge-on? Or flat? (with the narrow part standing or lying down?) I just watched one video - they did everything the other way around. After that I was completely confused.
How many supports do you have under these joists? How long were they?
It’s just that ideally I would make two fulcrum points and that’s it. The middle columns, after all, can also rise and fall over time from winter to summer, and the floor will either sag or bulge into a hump. Or simply the log will not rest on all points.
room dimensions?
under each block, as I already wrote, make a pillow to minimize heaving
room dimensions?
naturally the log is placed on its side, I try to have support points every 2 meters, sometimes 1.5
under each block, as I already wrote, make a pillow to minimize heaving
The total length of the room is 4.7 meters (the logs are planned to be this long) the width is different everywhere - it starts at 5.5 meters, then narrows to 3.5
I would put 4 blocks under the log
So that's probably what I'll do.
Flat slate is of course also an option - to close the base. But I don’t know how long it will last. I've never seen anyone seal the bottom with it. And then I looked at the dimensions - 1.5 meters is the maximum length. Again, the pieces need to be put together somehow. Or overlap it in two layers so that water does not leak.
What is the best way to insulate? I read that they pour expanded clay. But the minimum layer thickness should be 10-15 centimeters. If we take my area, it comes out, according to the most conservative calculations, 5.5 * 4.7 * 0.1 = 2.5 cubic meters. 1 cube of expanded clay seems to be 1800 rubles = 4650 rubles - just pour it on the ground anywhere. It will be painfully fatty. We need to come up with something more economical and effective. The premises are planned as heated residential premises. Gas is carried there. And no one will allow the street to be flooded. (this is why I again think that slate is not a very good option)
The main thing about the logs is the height. The span length (from support to support) for 150mm is no more than 2.5 meters. Well, 3, but they will already play a little. That is, for 4.7 - two spans, three pillars (stones, curbs).
Or you can knock down two 100x150 (to save on the vertical, you can take 50x150) with the letter T upside down. According to the loads, it should be enough for 5 meters (I don’t remember exactly, I need to raise the formula, see the indicated sites). Place two supports at a distance of 4-4.2 meters (the overhang near the wall, taking into account the thickness of the pillar, will not play a role). The lower beam can just be used as a shelf for the subfloor. Place such logs at a distance of 70-80 cm (between planes). Here you can use expanded clay between the subfloor and the finishing floor.
Again, as an option, put a normal concrete strip foundation on sand cushion just below the frame (to compensate for random movements) with a protrusion inward. And put logs 250 mm high on it (the same prefabricated ones).
There are many descriptions of flooring options, joists, foundations, etc.
You can lay 50x150 logs on the edge. Or make packages. Or "channel". Depends on the span length, available materials, floor coverings.
You can use fragments of curbs as linings. A couple of years ago there was a lot along the edge of the ravine behind Stroydepo and to the right after the cafe. People from all over the city flocked there. Accordingly, enterprising people recruited for themselves. Maybe there will be one now.
Stones under the joists can be poured directly into the level into the formwork made of boards and/or plywood using a hose with water. Well, or just make the formwork level and pour it along the edges.
The main thing about the logs is the height. The span length (from support to support) for 150mm is no more than 2.5 meters. Well, 3, but they will already play a little.
The foundation can be made from piles of flat slate and sand. About half a meter will be good. The slate here is just a limiter. Insulation - sand. Products, for example, from sewer pipe. Through two sheets of slate and sand.
If everything around is flooded with water, then without normal drainage it is all useless. We need to start with him. Either divert horizontally or drill drainage wells.
I also think so - cast the columns straight into the formwork level, so as not to have to worry too much about fitting. There was a lot of stress with the boards - all the good ones went into action, but I don’t want to leave rot in the ground, and I don’t know if there will be the required number of boards for the formwork. But the old slate taken from the roof was piled up. I think it will be suitable for formwork, so that it can be left there without removing it? I’ve just never tried sawing. I want to try sawing it to size with a grinder. Well, if it hurts, you’ll have to give up this idea.
at 30.4.2014, 15:15
Answer
3-4 vertical rods 8-12 mm in diameter. Very desirable from defrosting.
You can drill holes and stick round ventilation ducts (150mm) into them as formwork. The columns will be just a sight for sore eyes. But more expensive, of course.
Read the rules for cutting slate on the Internet. There it is necessary to wet the saw line. And there are still nuances.
Oh... I remembered, I also have an asbestos pipe. (about 20 cm in diameter) True, small. It won't be enough for many columns. But that's an idea. I saw this. Pour it in and that’s it. But again, it probably doesn’t cut well, just like slate. Need to try.
Why is there essentially fittings inside the pipe? It seems to me that it will be strong. Well, if there are any scraps left, of course I’ll put them in. And for such a small diameter, 4 rods are probably too much. One or two is enough.
Insulate the soil under a heated house – extra waste effort and resources, since the cold mainly penetrates into the underground space through the basement of the building. Therefore, for floor insulation wooden house First of all, it is necessary to arrange insulation of the basement part of the foundation. Then cold air will not penetrate under the floor and cool it. Please note that our ancestors in the villages did not insulate the floors, but walked around the house barefoot or in socks. This is because the houses had rubble, which were needed not only for sitting on them and husking seeds. In addition, to insulate the base, and therefore the floors, you can add soil or slag from the inside of the foundation. This insulating bedding is made along the outer walls under the floor to a width of up to one meter and a layer thickness of 250-300 mm.
During reconstruction floor insulation It must be borne in mind that the height of the underground must be at least 500 mm. Ventilation of underground space in summer time year is carried out through vents in the walls of the basement measuring 200-250 mm, which are located at a distance of 4000-5000 mm from each other on all sides. Wetting of the water supply pipe and the wall from it indicates that the ventilation of the underground is not at the proper height, which is why the temperature and humidity conditions in it are disturbed. And when high humidity air in the underground, moisture vapor settles in the form of condensation on cold pipe. In the cold autumn-spring period of the year, vents should be closed, or rather, plugged with a plug made of heat-insulating materials.
For wet soils, it is necessary to install a waterproofing layer in the underground, which can be made of crumpled clay, concrete, polyethylene film and other materials, and the surface level of this layer must not be lower than the ground level outside the building. In this case, the upper surface of the soil in the underground must be freed from the plant layer and cleared of debris.
For floor insulation inner space fill between the beams thermal insulation material, for which it is best to use non-flammable insulation based on mineral wool from glass or basalt fibers. Typically, for this purpose, products are used in the form of mats, which are laid on top of the rough flooring.
The use of polystyrene foam and similar materials on the inside of premises as insulation must be approached with caution. Almost all of them, if they do not burn, then support combustion, releasing toxic substances, which is fraught with extreme situations death or loss of health.
Of course, you can choose something from local inexpensive materials: such as dry coarse sand, sawdust or slag. You just need to take into account that they must first be prepared: treated with an antiseptic, dried and mixed with fluff lime to protect the backfill from breeding rodents in it. In this case, it should be at least 10% of the volume of material for backfilling. The mixture is thoroughly mixed until the composition is completely homogeneous. For more uniform mixing of organic materials with fluffed lime, all components are poured onto a wooden or metal shield and turned over with shovels until completely mixed.
When insulating a floor structure with local materials, the subfloor is lubricated with clay lubricant with a layer thickness of 15-20 mm, onto which, after drying, dry coarse sand, sawdust or fine slag is poured to a height slightly higher than half the beams. Sand or slag is poured with a centimeter layer of liquid lime mortar, dried well, and only after that the clean floor boards are laid.
Using for backfilling local materials, attention should be paid to their toxicity. If these materials are not tested for toxicity, then it may turn out that you, without knowing it, are placing an environmental bomb in the structure of your home, which can subsequently affect the health of family members. To prevent this from happening, it is best to use proven insulating materials, the quality and safety of which are guaranteed by appropriate certificates.
A vapor barrier layer is laid on top of the insulation to protect it from moisture vapor. It should be noted that it is necessary to leave an air gap on top of the vapor barrier layer, and provide ventilation openings covered with grilles in the corners of the rooms. In small rooms, the holes should be in two corners diagonally, and in large rooms - in each corner. In addition, along the top of the beams, every 500-600 mm, you need to make several cuts with a depth of no more than 20 mm. This should be done to ensure free air circulation in the underground space. Instead of ventilation holes You can use special skirting boards with gratings, and leave a gap of 15-25 mm between the floorboards and the walls. In addition, this gap is necessary for soundproofing the flooring.
All wooden structures The floor is made of dry wood, the humidity of which should not exceed 18%. In addition, when installing plank floors, measures must be taken to prevent wood from becoming infected with wood-boring beetles, house fungus, rot and mold. Therefore, the floorboards on the back side, and the subfloor boards, the lower crowns of the house, beams and joists on all sides, must be treated with antiseptic compounds. The retail chain has both ready-to-use protective equipment and “semi-finished products”, which should be prepared strictly according to the instructions included with the packaging.
Added: 05/29/2012 20:38
Discussion of the issue on the forum:
Is it possible to put insulation and waterproofing directly on the ground, and then not put anything on the floors at all? The ventilation in the underground-basement seems to be normal, but the wall near the water pipe and the water pipe itself are always wet in the summer.