When planning the construction of a wooden house, we often have to deal with a rather difficult choice of material. At the same time, it is very difficult to decide which is better - sawn timber or planed timber (not to mention the more expensive profiled and glued blanks).
In our article we will try to analyze in the most detailed way the features of the planed raw wood for the construction of houses, as well as describe the features of the technology of its use.
Briefly about the material
Planed timber is a billet of square or quadrangular shape, which is made from solid wood. For its production are used smooth logs without defects. The diameter of the log can vary between 150-250 mm, respectively, the size of the beam can also be different.
The most running are planed timber 100-100 mm, 100-150 mm, 150-150 mm and 150-200 mm.
Note! Due to the high precision of manufacturing, the dimensions of the parts may differ only slightly in thickness. Tolerances are no more than 1-2 mm.
Quite often the question arises, how does the planed timber differ from the profiled one:
- It should be noted here that although both of these materials are produced using similar technologies, when planing on the planes of the beam, protrusions and hollows of locks are not formed.
- Thus, with the planed material, all four faces are ideally smooth, while the profiled blanks have two flat edges, and two faces with connecting elements.
- On the one hand, this design complicates the positioning of the timber during the assembly of the walls, but on the other hand, even beams have a much wider range of applications.
Note! In some cases, profiled blanks belong to one of the planed varieties. To avoid confusion, in our article we will mean only square and rectangular section material in our article.
Another important parameter is wood moisture.
To date, the following types are on sale:
- Material of natural moisture - made from freshly sawn trunks, contains up to 40% of bound moisture.
- Storage drying blanks - are characterized by humidity up to 23-26%. Such indicators of water content are achieved by winter procurement of raw materials and aging of finished products in a ventilated areas.
- Chamber drying beam - prior to sale is subjected to forced removal of water from wood in special dryers. The moisture content of the finished product may vary depending on the task, but on average is 12-15%.
Technological process of production
The features of this material are explained by its manufacturing technology.
The production scheme is more complex than that of sawn timber, and includes the following steps:
- Initially, the selection of raw materials. Only whole tree trunks are started into operation, free from defects and damage.
- The most common wood species for the production of building material are pine, spruce, larch and cedar. In this case, spruce and pine bars are valued not only for strength and durability, but also for the attractive appearance of the treated surface.
Note! If you plan to carry out the minimum finishing of the inner surface of the lumber walls, we advise you to pick up fir-tree blanks, since they have a uniform light shade on the saw cut.
- After selecting the trunks, two options are possible: either the wood is immediately fed to the guard, or it is first sawn into bar blanks.
- In any case, the planing is done on special machines. In this case, the surface is processed according to the first class of purity, which makes it possible to use it without further mechanical processing.
Note! The planed profiled bar is made in the same way, but in addition to the guard it is profiled on a four-sided milling machine. The formation of the lock profiles is very time consuming, and therefore the price of the product increases compared to a simple flat part.
Further, the material may be subjected to chemical treatment in the factory: wood is impregnated with antiseptics and flame retardants. Due to this, the log house from the planed timber will not rot from moisture, in addition, the risk of its ignition will be significantly reduced.
As for drying, it is carried out either immediately before the stage of cutting the blanks, or after impregnation.
Comparisons with major alternatives
Timber planed 100x100 or 150x200 mm is widely used in the construction of capital buildings and structures in private construction.
However, other materials are used for the same purpose, and in this section we will try to analyze their pros and cons:
- The cheapest and most affordable variety is solid, sawn material. Unlike planed, sawn blanks are not subjected to surface finishing, which significantly reduces the cost of their production. Sawn timber of natural or storage moisture is cheaper than planed, but the walls of this material require additional finishing.
- We compared profiled parts with planed parts a bit earlier. Here I would like to note only the fact that the planed blanks are more “capricious” in the installation, since when positioning it is necessary to very accurately control the position of the beam on the plane, vertical and horizontal. And the shrinkage of an even material is stronger.
- Glulam exceeds planed in all respects, except for price and availability in the market. Far from everyone can afford to build a house of glued material, but planed wood has a more affordable price.
Conclusion из всего вышесказанного довольно прост: дома и бани из строганного бруса занимают тот самый средний ценовой сегмент, на который предпочитает ориентироваться большинство мастеров. С одной стороны, материал обладает приемлемыми эксплуатационными характеристиками, а с другой – его можно приобрести по вполне демократичной цене.
Building a lumber house with our own hands, we have to perform a very large amount of work. And the most time consuming process is the horizontal connection of the crown crowns.
When using profiled blanks, the installation process is greatly simplified. If we talk about a flat planed timber, then from the master requires all his attention and skill. You can master the technology only in practice, but first you need to study the theory.
Instructions for working with the material is as follows:
- Before installation, all blanks should be treated with an antiseptic and fire retardant that protects the tree from fire. If the wood has undergone a similar treatment in the manufacturing process, then this step can be skipped.
- We measure impregnated bars and cut to size with a chainsaw. If the dimensions of the wall provide for a longitudinal connection (i.e., the length of the standard blank is not enough), then at the ends we make cuts of the appropriate shape and size.
- Using a saw on a tree or chisel, we form locks at the corners. For planed timber, the most characteristic angular joint schemes are “in the bowl”, “in half-wood” and “warm corner”.
- We put the first timber on a covering crown, assembled from thick larch beams, saturated with linseed oil or oil. Fix the bars around the perimeter with metal anchors.
- On the top plane we lay out a jute tape. That at installation of wreaths the tape was not displaced, we fix it with small carnations or the construction stapler.
Tip! The edges of the tape should slightly go beyond the plane of the wall. In the future, we jute caulk in the cracks formed during shrinkage.
- Over the seal we place the next crown. Using a drill with a thick drill, we drill holes under the dowels with a step of 1.5 m.
- The nest should be deep enough so that the dowel passes through the upper timber and enters the lower one by at least half its thickness.
- We hammer or twist the dowels into the nests, constantly making sure that the blanks do not move beyond the limits of the wall plane.
- Separately we fix the corner, besieging the bars with blows of the mallet.
Shrinking and fighting it
One of the highlights in working with a planed non-profiled bar is its substantial shrinkage. Even in the process of drying and transportation, if the temperature is not followed, billets can warp. Well, already in the framework of the log house, the deformation of the timber is quite a common phenomenon.
To minimize the effects of shrinkage, it is worth taking the following measures:
- The first way to avoid changes in geometry with uneven shrinkage of the beam is the use of special jacks. Shrinkable jacks are plates connected by steel screws, which allow to raise separate parts of the log house for alignment.
- Also, to minimize shrinkage, you should carefully choose the time to start installation. The higher the air temperature, the more intense the tree loses moisture, and the brighter linear deformations appear. To keep the log house its geometry, experts recommend to make the assembly of the beam in the winter.
- Other ways of dealing with shrinkage include the treatment of the ends and planes of the beam with special compounds. These compounds not only normalize the moisture of the tree, but also protect it from rotting in the future.
And yet the shrinkage of the house from a bar - at least minimal - is inevitable. That is why after the assembly of the log house it is left to stand for a certain time. This time depends on the initial moisture content of the raw material, and may be from six months (if planed blanks of a female has been used) to one and a half years (when mounted from a sawn bar of natural moisture).
After completion of the shrinkage, the structure is subjected to thorough inspection. The revealed gaps are caulked, after which we repeat the protective treatment.
Wall decoration of planed timber
As for the finish, there are several points of view:
- On the one hand, the surface of the material of the first class purity implies that we do not have to look for than planing timber. The wall and so it looks quite presentable, and at least from the outside can do without plating.
- On the other hand, if sufficiently large gaps formed during shrinkage between the bars, the jute compactor may not be saved from blowing. Therefore, at least from the inside, it is necessary to make the lining of the wall panel or false bar, placing a windproof membrane under the decorative panels.
- If it is cold enough in your latitudes, then inside it is possible to provide full warming. Smooth walls will be an excellent basis for a framework on which a planed bar of 50x50 mm can be used.
Between the bars of the frame we place heat-insulating material with a vapor-tight membrane, and the casing is made of clapboard.
Planed timber 150 - 150, exactly, as well as parts of other dimensions, is somewhat more difficult to assemble than profiled materials. At the same time, the good performance properties of the timber, together with its reasonable cost, make it very popular. Of course, shrinkage will have to be overcome, but in the end, the savings will still be quite noticeable. In the video in this article, you can learn more about the specified topic.