Mauerlat for aerated concrete without Laying nets
Construction of houses from aerated concrete in recent years has reached a very high level of popularity, and there is no clear trend towards a decrease in contrast, this material demand is growing, which is understandable for several reasons. Solid block sizes along with their clear "geometry", the use of an optimized mixture for masonry-glue solution - all this allows the erection of straight walls as soon as possible. However, the resulting walls are relatively small mass, that is, do not have a big load on the foundation already initially have a pretty good thermal insulation qualities - that is, costs for subsequent insulation works are not so significant.
Mauerlat for aerated concrete without Laying nets
But there is almost any type of aerated concrete one "weak spot". We are talking about the difficulties encountered when connecting to other structural elements to the porous walls. "Classic" fasteners, often it becomes useless as it is not retained in the thickness of aerated concrete, and it is necessary to look for other solutions. Well, if the task - to attach any supporting or decorative detail - is enough conventional screws. But if the problem lies in securing a powerful beam mauerlat?
As a rule, such bearing structural elements filled with a solid reinforced concrete belt. However, some amateur builders, apparently for reasons of economy of time and materials, try to find ways how to fix mauerlat for aerated concrete without Laying nets. Let's see how this is possible, and whether it is necessary to resort to such a decision.
A few words about the importance of mauerlat
What is mauerlat and why is it needed? Man, inexperienced in matters of construction, it is often tricky word does not say anything. Meanwhile, we are talking about one of the most important carriers of the building construction details.
What is the foundation - they know, probably all. So, on the functionality mauerlat can be compared with the foundation tape. However, she is responsible for the load transmitted to the whole building, and mauerlat - only those that are produced during the operation of the entire roof structure - roof system, roofing, insulation "cake", the inner lining rays (if any), and etc.
With certain assumptions, mauerlat value for the roof structure can be compared with the importance of the foundation - for the whole house.
A load here can be considerable, and the most dangerous - be bursting, perpendicular to the wall surface direction, that is, work for their destruction. All the matter in the corners of the roof stingrays - this is what gives such a decomposition of vectors of force application as the severity of the design of the roof, and when external load - snow and wind.
Particularly dangerous bursting such point loads transmitted from the rafters, wall lined piece of material - brick or masonry blocks (which applies aerated). Hence, it is necessary as much as possible to evenly distribute the load falling out along the entire length of the wall. And, again, by analogy with the foundation tape, this can handle a powerful wooden beam, which tightly rests on its entire length in the end wall.
Load of rafters is not transmitted directly to the block wall - thanks to mauerlat it is distributed evenly over a large area all over the walls
The second remarkable quality mauerlat - a significant relief assembly work during installation of roof system. Agree that fasten each rafter foot to the main wall is much more complicated than, as they say "tree to tree". With the presence mauerlat detached very wide application of various compounds of circuits from "deaf" to mobile, using a variety of fasteners.
This is - just a few of the possible options for fixing rafters at the lowest point in the presence of mauerlat
As usually applied mauerlat wooden bar section 100 × 100 mm and above (usually as a function of the massiveness of the roof structure selected another 100 × 150, 150 × 150, 150 × 200 mm). Very often rely on tacit, in principle, but generally effective - mauerlat thickness should be not less than two thicknesses of the rafters.
Width - depending on the thickness of the wall on which it is installed. In this case, try to place the timber so that it does not come flush with the wall surface either outside or inside. So it will be easier to protect the wood from the adverse effects of the environment, to carry out insulation of a rather complex in terms of the normal insulation assembly. This rule is not mandatory, but if you read the advice of masters, they are all almost unanimously advised to leave on each side at least 50 mm from the edge.
It is desirable that mauerlat bar was still somewhat narrower than the wall - to remain on both sides of the indentation of at least 50 mm.
Mauerlat can be made from timber, but this solution is not seen the best - operation attaching to the wall, and then tie rafters will become much more difficult and, therefore, require high skills in carpentry.
It is understood that because of the high responsibility of the structural element of the roof, for such purposes try to choose the dried wood of Class I that has no distortion, expressed knotty, cracks, biodegradation characteristics, and other defects.
The quality of wood for mauerlat not worth saving - it has to be top-notch with no defects or signs of biological destruction
For mauerlat generally recommended a select hardwood. But to find such material - is not easy, so the quality is most often used pine, but subjecting it to rigorous selection: savings as in this case - quite acceptable.
By the way, mauerlat may not be wooden. usually channel or I-beam - for example, if you plan to create a truss system or prefabricated welded steel trusses, and then as mauerlat steel beam will be applied. However, in the practice of private construction to such decisions rarely resort - "classic" is wood.
Mauerlat can not be applied on the walls of the timber or timber (it will fulfill the role of the last series - the top rail), and frame houses - for the same reason. Sometimes refuse mauerlat when walls were built of durable, resistant to bursting point and load of the material (e.g., concrete), and wherein the roof structure includes bracing trusses to the removal of the outer overlapping beams. Walling is composed of piece goods, without mauerlat do not succeed in any case.
It is clear that in order to mauerlat fully carry out its functions, the reliability of its mounting on the wall should not cause any concern. With concrete, stone, brick walls - easier, since there are many ways to secure fixation rod on the end wall. For example, when laying ceramic or silicate brick made of wooden bars Bookmarks. This makes it possible to then use for fixing mauerlat conventional steel braces. But to perform such favorites with gas concretes - is absolutely hopeless occupation, you can not even try, since no reliability is not ensured. We have to look for other ways, which will be discussed later in the article.
At a laying of a brick wall often made wooden bookmarks, and then mauerlat can reliably fix the brackets. With gas concretes such a "number" does not pass!
On the walls of aerated concrete mauerlat recommended to perform on the "closed circuit", ie in the form of a frame, completely encircling the entire perimeter of the building - so it maximizes the reliability of the design. However, this does not always possible - for example, in the case where from the same foam blocks being layout gables. So, the more reliable must be done fixing timber to the end wall.
How is the gable truss system?
Along the way we have already once the reader is referred to the size of the rafter - this to a certain extent it depends on the cross section mauerlat. And here How is the gable roof truss system, taking into account the slope angles and all the pull-down loads - read the special publication of our portal.
As can be attached to the timber mauerlat silicate wall without Laying nets?
First of all, the builder, in front of which stood a similar problem should clear himself to answer the question - "Do I really have no way to pour a reinforced concrete belt to have no problems at all?" Why? - Yes, because any of the options offered below is not devoid of certain shortcomings. And also - the ability to install itself without mauerlat Laying nets - rather doubtful, and taken with many reservations.
If you flip through a real construction reference books, then, perhaps, the theoretical justification mauerlat fastening on aerated concrete wall without Laying nets - and you will not find
How many do not seek, it is unlikely to succeed to find a comprehensible criteria, when experts say unequivocally - yes, you can do this without silicate concrete wall Laying nets. There are a lot of all sorts of "if", in which, like, we can hope for the success of the installation.
- If a house or a small outbuilding (evaluation criteria, alas, no).
- If the roof is not too complicated and heavy construction (for example, that it is a simple gable roof of, for example, corrugated or metal - all other roofing materials, together with his crate will be harder).
- If the climatic conditions of the region do not involve the construction of a large snow loads and wind pressure (and who can guarantee that will not happen weather anomaly?).
- If the design of roof system will minimize arching load. This can be achieved:
&# 8212; Stop using hanging rigidly strapped horizontal puffs.
&# 8212; Naslonnyh using trusses, with obligatory support at the ridge of the compound if the connection point between the rafters on a ridge of the hinged connection is provided, and fixing to mauerlat assembly involves the use of moving, sliding connections.
Rafters must be rigidly linked or puffs (for hanging scheme), or, if naslonnyh rafters - have hinged on the ridge and a movable sliding - by mauerlat.
In short, the list of conditions to try to do without Laying nets (and that without full confidence in the success of) - is big enough. And probably, it is necessary to think ten times before you choose this path.
Nevertheless, the web offers several ways to mount the beam directly on mauerlat silicate wall without filling Laying nets. Let's try to understand them.
Mauerlat mount with wire
One of the easiest ways that is often used in the construction of brick walls. In this case, approximately 4 to 5 rows ÷ closure laying between stacked rows of tufts of steel wire with a diameter of about 3 mm (at 3 ÷ 4 wires in the beam), so that they peeped and the outer and inner side walls. The length of the release of "braids" are doing so that it can provide coverage mounted at the end of laying mauerlat timber and allowed to seamlessly generate reliable twist and tightness of the wire loop. Step arrangement such povodochnyh bookmarking typically selected at a pitch trusses installation, so that the fastening components accounted mauerlat between adjacent rafter pairs.
Installation beam for waterproofing mauerlat forming wire loop
Preparedness wall on her butt fit waterproofing. Then the top timber is installed, leveled, and then is made creation and tightening the wire loop. Tightening is usually carried out using crowbar (mount), ensuring maximum contact pressure tight timber wall.
Wire loop after tightening by means of the mount - mauerlat pressed firmly against the wall.
It would seem &# 8212; here it is, the simplest solution. But, look: all the examples shown - only on a brick wall. Write that this method works well with silicate blocks, only the tab wire "braids" hold for about two rows before the end of the masonry.
Write something written, but no reliable evidence for the reliability of this method could not be found on the Internet with silicate walls.
For personal sensations - if the wire is not under heavy load, and even more so - with the possible vibrations, for example, when a strong wind, run as a "saw blade" is gradually biting into silicate blocks (which can be hand-cut saw)? After all, this is a violation of the integrity of the masonry, and the weakening of fixing mauerlat on the wall, with all its consequences.
In a word, it is not so obvious just ...
Fixing rod with anchors or anchors
It would seem &# 8212; the easiest and most reliable way, practice-proven and time. All true, but only if we are not talking about the gas silicate. The increased fragility of this material may be the surprise, when tightening or screwing the anchor dowel formed crack or even spall.
Of course, on sale today, you can find a considerable range of fasteners, designed specifically for aerated concrete walls. But, you see, it is one thing to fix the furniture, home furnishings, or even a framework for the insulation of walls - and quite another powerful beam, which becomes the basis for the entire roof structure.
Anchors and special plug, which can be done fixing to aerated concrete.
How to use this calculator - probably do not need to explain. The only caveat - if you plan to use U-blocks of factory production, they have a channel fill Laying nets slightly converge downwards in the shape of a trapezoid. In order to accurately calculate the volume in this case, the width is indicated by the results of soundings above - minus 10 mm.
Outcome of ingredients will be shown as a weight (more convenient to purchase), and in bulk, in liters and buckets equivalent (more convenient, e.g., for dispensing when loading concrete mixer). All proportions are composed of portland cement calculation application PC-400 to yield strength of the concrete grade M200.
As can be seen from the above calculations, no nightmarish concrete volumes are expected, and the cost, I think, a real Laying nets can cost even cheaper than any exotic options mauerlat attachment.
Therefore, once again I repeat with the strong recommendation - do not be lazy! House of silicate blocks - it's a good idea, but it requires a mandatory reinforced belt in the upper trim. Only then can we be sure of the durability and reliability of their homes.