The better to fix the board with a dowel or a nail. Wooden or metal dowel. Ready houses from a bar
This deeply specific question - why can't nails be used instead of wooden dowels? - is answered by someone who has seen a lot of things in wooden construction Grigoriev S.P.
In my opinion, when I see that some young builders use metal nails when assembling wooden log structures, this is not just a violation of all building codes, but a gross deviation and violation of the main rule of construction wooden structures, especially the walls. Why is it still impossible to use nails instead of wooden dowels? Yes, the thing is that iron nails will not later allow the wooden log walls of the log house to sit properly, which should happen as a result of the drying of the log walls wooden frame. Proper shrinkage - shrinkage of wooden walls in a log house is possible only if wooden birch or oak dowels are installed in a log wall in a checkerboard pattern. Metal iron nails “tightly” fasten the logs together, which later leads, when the log house shrinks, to warp the walls and form huge gaps between the logs. Thus, when using metal nails - a metal dowel, in the walls of the log house in a year - one and a half, giant gaps form between the logs, through which the log house is blown through like a sieve. In this case, no interventional insulation can help save precious heat in the log house and the building will always be cold and blown by all the winds.
Many builders recommend assembling houses from profiled timber on wooden dowels. What is a wooden dowel? The old proven method for bonding modern materials? Yes, there are a lot of reviews on the Internet that the timber assembled on the nails did not sit down and there were through cracks. But cracks are formed not because of nails, but from crooked builders or economical customers, as often happens recently. The brigades believe that if the house is an economy class and the salary is small, then it is necessary to collect them as quickly as possible in order to a short time Complete multiple objects and earn a normal salary.
When we assemble a profiled timber for nails, we must drown the nail head by 1 - 2 cm. If the nail is not drowned, then after the wood has dried, the nail begins to stick out a little and does not allow the next timber to sit in place, because of this, cracks are obtained.
We also had orders for exterior decoration of 10-15 year old log houses. All of them were assembled on pins, and the walls of all of them were in a wave.
Because of what the timber walls assembled on the dowels bend.
In the old days, in order to fasten two logs with a diameter of 30 to 50 cm, nails were required at least 80 cm long. Such nails do not even exist today. Instead, wooden dowels with a diameter of approximately 30 mm were used, the holes for them were drilled 5 mm smaller than the diameter of the dowel, so that the dowel would clog very tightly and after the wood had dried out, the log would not go into different sides, which can lead to deformation of the frame. Because of this technology, a log cabin shrinks into place in at least 5 to 10 years.
Wooden round dowels with a diameter of 3-4 cm are used only for thick wooden walls, such as a log or cylinder. If you use a dowel in a profiled beam, the following happens - the thickness of prof. timber 14 cm. The dowel is drilled in the middle, leaving the thickness of the wall from the outer edge to the dowel no more than 5 cm. Because of this, the initially dry dowel absorbs moisture very well in autumn and spring, and when dried (in summer) in places where the timber did not sit down, it begins bend. And if the beam starts to bend the dowel will not hold it, it will simply bend like a beam and after drying it will remain so. The minimum thickness of the beam for such a dowel is 200mm. Plus, the installation of dowels should be done in a checkerboard pattern, which increases rigidity and reduces the bending of the walls.
A thin profiled timber does not have sufficient weight, the lower crowns fit well, they are pressed by the entire weight of the log house. But the upper veins on the dowels weigh for years, the own weight of the beam is not enough to settle, all the same, this is not a log. Tops fit easier on nails.
Now for the best shrinkage of a bar there is a modern spring knot "POWER". True, while this is an expensive pleasure, approximate cost installation of a node for a house of 6x6 m. will be 46,000 rubles.
Any calculations will show that during repair, construction or reconstruction - the share of fasteners, in comparison with other materials, accounts for negligible costs. However, if the choice is wrong or if misuse these components, we risk the reliability and functionality of the entire facility.
Therefore, there is an unwritten rule: "you can not save on fasteners and consumables." But interestingly, sometimes the most affordable and inexpensive solution can be the most successful. This happened with pins - special parts for assembling log cabins, which can be made of wood, polymers or metal. Which option is better and why, let's try to figure it out.
Tasks that are solved by nagel
It has always been believed that traditional wooden architecture in Russia they managed "without a single nail." But even hereditary masters of aerobatics use something. This is a nagel.
To be more precise, dowels, which are also called "dowels" - this is not quite fasteners in the traditional sense. The thing is that the dowel works differently than, for example, a nail, screw or pin.
To install it in each element of the assembled wooden wall after 1.5-2 meters, holes are drilled that are comparable in diameter to the cross section of the dowels (so that the dowel enters without undue effort). Drilling is carried out strictly vertically and strictly along the axis of the wall.
These holes pass through the newly installed beam (or log) and almost completely through the beam / log, which is located below. It should be noted that there is a technology when not two, but three crowns are stitched.
Then the dowels are driven into these holes and the dowel is sunk 3-5 centimeters so that as the house shrinks, the dowels do not rest against the higher beam / log.
The dowel installed in its place does not fasten or tighten the logs or beams together. It serves as a mortgage element that prevents the crowns from moving relative to each other. Logs are prone to horizontal shift and “turning out” during the shrinkage of the log house, since when moisture is lost, the wood begins to warp. That is, the dowel allows you to keep the wall even, but at the same time it should not interfere with the free vertical movement of the wall elements so that the crowns do not hang, and subsequently no gaps form between the crowns.
We emphasize once again: one of the most important conditions correct operation pin is a clear correspondence between the diameter of the fastener and the diameter of the drilled seat.
What is a wooden dowel
Nagels, which can be bought at numerous outlets in our country, in most cases are wooden. These are whips from one to one and a half meters long, with round section. In some cases, builders use an edged bar as a dowel, but it, resting against the walls of the nest only with its edges, can become very loose over time. Besides total area its cross section (and hence its strength) will be significantly less than if a round dowel was driven into the same hole.
The diameter of standard dowels is either 30 or 25 mm. The choice is made depending on the dimensions of the wall materials used. The defining threshold is considered to be 150 mm. If the diameter of the log is less than this value, then it is worth ordering a dowel with a section of 25 mm, and if more, then dowels of 30 mm are better suited.
If we talk about the types of wood used, then the best option is expected to be an expensive oak or beech, since their wood is the most resistant to mechanical stress. In turn, spruce, pine and aspen are at the other extreme - products made from them are inexpensive, but will be too soft for use for these purposes. The golden mean is birch. Turned birch pins, even in the presence of knots, can cope well with the tasks.
The advantages of birch dowels include profitable price and availability. If they have the same moisture content as the material of the crowns, they will work as a whole, and if they change in size, then they will do the same. In addition, unlike metals, wood has a low thermal conductivity, which is why this embedded part will never become a cold bridge, will not begin to rust, become covered with condensate ...
Metal dowels and fasteners for assembling log cabins
A dowel made of metal, by definition, will be stronger than a wooden one of the same cross section, but not everything is so simple. This statement will only be true if complete analogue by section size.
For example, it is not uncommon to see how builders use steel reinforcement 10-12 mm, and with corrugation, which is hammered into narrow holes with great resistance with sledgehammers. As a result, because of the ribs stuck into the wood, the crowns cannot sit freely and hang on the metal - cracks appear, the walls of the house begin to blow through with all the winds.
Due to the small cross section of steel dowels and the ductility of ordinary black steel, logs bend and wedged even smooth metal dowels during shrinkage. Therefore, powerful nails are also not the best way although they are used quite frequently.
This problem would not have arisen if smooth rods with a cross section of 20 mm or more, or pipes with a cross section of 25-30 mm, were used. But the cost of such metal dowels would be simply unbearable.
There is a technology when, instead of pins (in the usual sense), a similar function is performed threaded studs. Meter studs are fixed with one end in the foundation, then crowns are put on them. As the walls are assembled, the studs are built up with couplings. Using nuts with washers, craftsmen get the opportunity to tightly connect the piece wall material, including tightening fasteners as they shrink.
Basically, this solution has found application when working with very dry profiled timber. AT normal conditions they just make it harder.
Studs are well suited when you need to fix logs that are joined to each other by the ends. To do this, a pair of cuts and a pair of triangular / round extensions for nuts are made in the body of the crowns.
A similar tightening work in the “overcut” zone is performed by hardened U-shaped brackets, but they provide a slightly less reliable connection.
Self-tapping metal screws and crackers can act as analogues of wooden dowels. But since when screwing the crowns, the latter cannot be compacted as they shrink, the scope of use of such fasteners is limited exclusively to glued profiled timber with a minimum percentage of moisture, the walls of which practically do not shrink.
05.02.2016 08:24
When building a house from a bar, two main types of fasteners are used - these are nails and dowels. They work in tension and bending, which is why they are so popular.
Russian Houses uses both types of fasteners in its work. But it should be understood that when building a house from a bar, it is better to use dowels, but for building a bathhouse or country house Nails are fine too.
What is the difference between these types of fasteners? Both of them serve the same purpose - to prevent the timber fasteners from moving. But at the same time, the assembly on the dowel and on the nails have many differences. Let's take a look at them in this article.
Nails as an element of timber fastening
Nails are made of metal and therefore conflict with wood, but are also often used in building houses. And this is sometimes quite justified, since this type of fastening has its advantages:
- Assembling a building from a bar with nails is very fast;
- The cost of such work is much lower.
But, at the same time, nails have their drawbacks:
- Nails are susceptible to corrosion;
- When compared with dowels, the bending work of a nail is much worse.
In addition, when assembling a beam on nails, one must also take into account such a moment as the depth of their recession. It should not exceed five millimeters, otherwise, when the building sits down, gaps may form.
Assembling the beam on the dowel
If you translate the word "nagel" from German, then it means "nail". At its core, it looks like a pin made of wood. Nagels can be square or round. They allow you to prevent the displacement of the elements of the beam and keep them at a certain level.
The main requirement for such fastening elements is that they must be smooth, otherwise gaps in the wall may occur.
- Benefits of assembling on dowels:
- They are not subject to corrosion;
- Excellent work on the bending of the timber;
- They are not afraid of the influence of temperature differences;
- The assembly on the dowel subsequently does not interfere with the shrinkage of the walls.
This type of fastening dries out simultaneously with the walls of the timber. The company "Russian Houses" recommends the use of dowels from more than hard rock wood than the timber itself. For example, if pine timber is used, it is better to use birch dowels with a round section, with a thickness of at least 25 mm.
Wooden "nails" have absolutely no flaws. If you need to build a house from a bar - this is perfect solution, because this type of fastening is a homogeneous material. The only negative is that such work will cost more, and building a house will take a little longer than using metal nails. It is also important to prepare wooden pins in advance.
The construction of walls using this technology should be carried out in compliance with all the rules and requirements, but then the building will please with strength and durability.
With the help of one dowel of the corresponding length, two laid crowns can be fixed at once. It is hammered into pre-made holes with a wooden mallet. The blows should not be strong - otherwise you can damage both the fastening element itself and the bars. It is necessary to hammer in a wooden pin so that it does not reach about two centimeters to the bottom of the hole.
That shrinkage was then carried out evenly, the holes must be made strictly vertically. The first pin should be hammered in about half a meter from the corner, and all the rest - in a checkerboard pattern, at a distance of about two meters from each other.
There is only one conclusion to be drawn from the foregoing - it is quite possible to use nails when assembling a beam, but only if a cottage or a bathhouse is being built, which are subject to exterior finish. If the owners will live in the house permanently, it is better to build it with the help of wooden pins.
Construction Company SK-DOM 53 assembles houses from timber for nails and wooden dowels
Assembling a log house on nails building technology contractor! Assembling a log house on wooden dowels according to the construction technology of the contractor!
Assembling a house from a bar to nails:
Foundation of the house
Strapping: Beam 150x150 mm
Floor logs: Beam 50X150 mm, after 70 cm
Double floors:
Draft floor: edged board 20 mm
Finished floor: dry grooved board 36 mm
Walls and partitions
Log house: Profiled timber 90x140 mm natural humidity, has a spike and a groove, is not sheathed with clapboard
Partitions of the 1st floor: Profiled timber 90X140 mm of natural humidity, has a spike and a groove, with a saw cut into the main walls of the log house
Assembly of the log house: Crowns are assembled on nails 200 mm deep into the timber. Flax-jute insulation is laid between the crowns of the log house
Log cabin corners: Carried out in a warm corner
Ceiling height: 1 floor – 2.4 m (+/- 5cm)
Interfloor ceilings: Beam 50X150 mm, after 50 cm
Roof and roof
Rafter system: Beam 40X100 mm, after 1m, lower leg truss system from a bar 50X150 mm
Lathing: Edged board 20X150 mm or 20X100 mm, after 20 - 30 cm
Roofing: Ondulin, color - red, green, brown. Waterproofing under the roof
Skate height: 3.4 - 3.5 m
Issues, overhangs: 0.3 m. Hemmed with coniferous clapboard
Gables: Frame, sheathed with coniferous clapboard on the outside
Attic
Attic frame: Beam 40x100 mm
Walls and ceiling of the attic: Sewn up with forced-drying Eurolining<<В>>
Partitions: Frame, sheathed with dry forced-drying eurolining, class<<В>> , without insulation (If available in the project)
Ceiling height: 2 fl. - 2.2 m