What to do if the floor has rotted: we put a “diagnosis” and determine the repair path

As the famous Ranevskaya liked to repeat, "the weaker sex is rotten boards." Yes, the situation itself is one of the mostnotPryatnyh - the wooden floor has served you faithfully for more than a dozen years, and at some point they begin to resemble ship boards: somewhere they stagger, somewhere they bend, and somewhere they break completely ... Going through the floor is easy. But, even if you get expensive and waterproof wood, put a more solid waterproofing and even hang a hygrometer - this will not save you from repeating the same situation after a few years, if you make the same mistakes again when arranging. Therefore, let's learn how to solve such problems even before the start of such a laborious repair.

To begin with, look at what happens if you don’t do everything wisely on time:

We make a "diagnosis": why did the floor turn into dust?

But first, let's learn how to make a “diagnosis” of rotten floors. So:

1. Boards turned into dust, but at the same time you do not feel obvious humidity? And is the wood seemingly clean? This is not a rotten floor, but the floor eaten by bark beetles. How to deal with them - in another section of our site.
2. The boards are rotten, moisture is not felt, but on the boards themselves there is some kind of plaque and something like white foam? This is a fungus that does not always appear due to dampness; rather, it is brought in with already diseased boards.
3. Boards turn into dust and even blackened in places? This is a sure sign that your floor rots, and it rots due to water.And water can be selected for it in a variety of ways, and this is not necessarily just groundwater from the basement. Everything is much more complicated here, and now we will gradually sort this out.
4. Boards rotted, and insulation - in water? Well, if moisture comes from the house (for example, the walls are to blame), then this will be noticeable primarily on wet insulation. In this case, you need to work with the house - at least for the first time installing a modern air dryer.

Determined what happened to the boards? Move on.

All about the process of rotting wooden floors

One source of rotting of any wooden floor is water. The constant access of moisture and air to this material has a detrimental effect on it, especially the frequent wetting-drying cycles.

To determine the exact cause of rotting floors in the house, you should note the following factors for yourself:

1. The history of construction. What and what, whether the blocks were dry, for example, how the foundation was waterproofed and what the roof was overlapping with.
2. Weather. How often it rains, and is there slush.
3. Age at home.
4. How is air exchange organized? For example,for the products to work correctly, the diameter of each of them must be at least 25 cm.
5. Have all the rules been observed when installing floors.

The first signs of the beginning of rotting the floor - this is the expansion of the boards and the "game".Already at this stage, the floors can be saved - without a complete overhaul.

The most common sources of moisture in the underground are ascending moist flows from the ground (especially if the groundwater is high) and too humid air from outdoor ventilation. How to understand what exactly you have? Perform this simple test:

1. Well plug all vents.
2. Open the hatch in the underground or arrange a small hole against the wall to allow air communication between the room and the underground space.
3. Underfloor heaters so that the air temperature there becomes the same as in the room. Those. align her.

Now check to see if the underground air remains as humid - if so, then the moisture from the ground is the source. It can be isolated with modern materials, laying them on the ground and covering the foundation with moisture. We also note that many of the types of oils that the floorboards are coated with before installation also contribute to wood decay.

The most common causes and solutions

Let's look at the most common options, because of which the floor begins to rot:

Option number 1. The souls cannot do their job

There are too few vents in the house, up to 6, and they are organized low to the ground. Because of this, blowing is almost impossible, and the medium becomes too wet over time. Rotting logs and floors.

What to do: instead of a heater, lay a moisture-proof membrane in the floor cake, which will control the movement of water. Next, arrange the ventilation gap with the help of counter-rails across the beams. The clearance and slots of the purge must be a ventilated baseboard. So possible moisture will be drained. And, if the ventilation does not work enough, there should be any other ventilation under the floor. Usually this is a metal corner in the floor with holes - it is enough.

Option number 2. The ground is too close

The wooden floor is laid on the logs, and under it is the earth, at a distance of 20 cm. Such a floor will deteriorate very quickly. And it is precisely such constructions that mountain builders often make in private homes - quickly and angrily, as they say. Sometimes, however, instead of earth, wet clay can be found there, and the result is the same.

What to do: unambiguously remodel the floor: waterproof the pie into a pie, raise the floor itself higher with adjustable moisture, and protect it well from dampness. Another option is to put a geofabric on this land, and sand with good tamping on it. He will not carry water upward, even if there was no geological fabric (this is prevention) - as on the seashore, sand is dry, if you dig deeper - wet.

Here is an example of the proximity of the lag to the ground, and in the process of replacing the floor they were raised:

Option number 3. Hopelessly Raw 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 completely abandon it, foam the products and completely fall asleep with clean river sand. At the same time, water every layer abundantly and tamp it well. Lay a plastic wrap and insulation on top of the sand cushion, then plywood, and the floor itself is already on it. And, most importantly, remove water from the house as much as possible - using external drainage. Usually even pipes around the house are enough, but sometimes the townsfolk build nearby small reservoirs of groundwater - deep holes. From there, it is not difficult to even pump out water.

Option number 4. The vapor barrier is not properly installed.

It often happens that a certain material is laid as the floor cake was thought out, and then the boards suddenly rot. This is because the laying floor has not studied the instructions for the vapor barrier itself - different manufacturers have very different requirements for its installation. So, materials of one brand should fit snugly against the insulation, others should have a ventilation gap between them.

What to do: changing the floor, you can use the same insulating material, but this time well study all the information about it.You can consider everything more carefully in the same section of our site. And note that vapor barrier on the bottom of the floor cake can be done 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 above it will be necessary to equip good ventilation.

In this photo instruction, the rotten floor in the bath was due to improper use of the membrane, and now it has been completely replaced:

Option number 5. Forever wet insulation

The insulation gets wet, which is why the logs and floor boards in contact with it begin to rot.

What to do: remove the vapor barrier from the bottom of the insulation and fix the membrane in its place. If this does not help, remove this insulation altogether, and insulate the base and the blind area instead, completely plugging all the vents. Heat losses will be no more, and the problem will be completely solved. And first of all, determine where the floorboards began to gain moisture. So, she can go from the underground, or from the house itself.

Look at an example of how a rotten floor was replaced and its cake was properly arranged:

Option number 6. Under the house - a real swamp

For example, today they began to actively sell plots with the former swamp for private development. And gender problems already in the first few years. Whatever the floor is covered 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: equip a special drainage with a separate pump under the floor, and one more - external, without a pump, simply with water drainage. The problem will be solved.

The hole for the purposeful drainage of water in the basement base can be done this way: either with the help of a concrete reinforced screed with a slope, or simply laying a ruberoid with an overlap at the edges. In addition, if your underground is damp - in no case do not put laminate or linoleum on the wooden floor. They simply will not let moisture in, and the floors will begin to rot. When laying a new floor instead of a rotten old one, be sure to at least twice treat the boards with an antiseptic.

Here's how to protect such a floor - this one also rotted from a swamp under the house:

Option number 7. The floors were insulated too hard

Yes, everything is warm - it remains in the house, but now it will freeze under the floor in cold weather so much that it will thaw all summer - and until autumn. Bottom line: a huge amount of moisture.

What to do: revise the design of insulation and simplify it a little.

Option number 8. Excessively humid air inside the house

Let's explain in more detail. If ventilation, namely the exchange of walls of the house with the external environment, is not arranged correctly, then in the warm season this is not yet felt. But at the very first furnace, internal vaporization is significantly enhanced (moisture is given away by walls and ceiling), warm air goes up, as we know from physics, cold air goes down. And condensation forms on the floorboards, and it is in the coldest place - on the insulation. Please note: do your walls get wet where external moisture could not get in? And for accuracy, get a regular hygrometer and measure the air humidity inside the house in winter.

Another striking sign that 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 air vents in the house, close the vents, and in this way drive the humid air into the street.

Option number 9. From old age

It happens that the floors rot and just in a very old house. Such a property of wood.

What to do: just replace. Only work carefully with a jack - if the house is wooden to everything. And carefully consider the lags - if possible, they also need to be replaced.

Here's what a competent complete replacement of a wooden floor looks like due to rotting in old age:

Option number 10. Lack of ventilation between floor and wall

Those. the floors are made close to the walls, which in itself is a violation of all technologies.Such a construction is especially vulnerable in a wooden house - the lower crowns will begin to rot first, and then the floor itself. The log house itself will not live long without intervention.

What to do: completely change the floor cake and throw out rotten boards (not all could have deteriorated). It is advisable to replace everything with a good concrete floor, especially when it comes to the bath. So, for a Russian steam room, apply this floor cake:

1. Sand pillow.
2. Rubble.
3. Screed in 3 cm thick.
4. Waterproofing film.
5. EPSP.
6. The same film.
7. Reinforced screed 10 cm thick.

Why film? It is needed both from below and from above, because above the floor there will be a washing or steam room, and these are especially humid rooms. Secondly, she will not pass cement milk into the insulation during pouring screeds.

Option number 11. Only beams rotted

If you find that only the beams rot and the floor is not touched, most likely the foundation freezes very much in the cold season, and condensate accumulates on it from the inside. Beams are the first to deal, of course.

What to do: it requires the dismantling of old beams. Further, where the boards are in contact with the basement or with the walls of the house, waterproof them with rubemast or glassizol, in several layers.

Use a geomembrane as a waterproofing under the floor - this should generally be during construction, like an axiom. Glue its edges to the foundation with a double-sided bitumen tape, and forget about the underground moisture. If you change the lags, make them with a slight bias to the side - so that the condensation that appears does not linger on them anymore, but flows down. And for the release of this water, it is also advisable to make a drain under the foundation.

Option number 12. The floors rotted in the apartment

This is a sure sign that they lacked ventilation.

What to do: It’s not difficult to organize the necessary holes - you need one under the battery and one on the opposite side.

Reason: necessity or evil?

By the way, in recent years, the underground has been increasingly being built without thinking. So, the masters call those “Russian tradition - first to drive humid air underground, and then actively drive it out”. Therefore, today, more and more often, the foundation is just well insulated, the floor is all. So the floor will never rot. What does this design solve?

Let's take a closer look at this point. For example, in spring, the air in the street is much warmer than underground, and besides, it is also humid (snow is melting). And this warm and moisture-saturated air penetrates through the air under your floor and immediately settles in the form of condensate on cold boards. And they spend a lot of time in this dampness - until the summer. Is it any wonder that in several years, wooden floors are completely rotten? And through the same vents, hordes in the autumn rodents make their way into the house. That is why today other structural solutions are already actively used, and ventilation is carried out in a slightly different way - through the house itself.

Such an underground is called indoor air-conditioned, i.e. mechanically ventilated. The fact of the matter is that if the temperature of the underground and the rooms do not differ much, then condensation will not occur on the floorboards. On the other hand, if your underground is still ventilated and will be ventilated by air, then the movement of air from it through the floor must be completely blocked.

These are the solutions to this problem - everything is actually very simple.

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