Walls of straw blocks have the following characteristics

Walls of straw blocks have the following characteristics:

• The straw wall independently holds the load of a simple one- or two-story building, while maintaining the vertical;
• Withstands any wind load, restrains strong winds and moisture penetration into walls;
• It has high thermal conductivity - one of the best existing insulation materials;
• The risk of wall getting wet is reduced, there is no penetration and retention of moisture in the walls;
• Thatched walls do not shrink over time;
• Thatched walls protect against external and internal vibrations during strong winds;
• The corners are kept intact;
• At straw walls increased seismic resistance;
• Clay plaster applied to a straw wall holds without additional reinforcements;
• When applying clay layers two or three times, the wall almost never crackes even with small earthquakes;
• Dampens the mechanical load on the clay layer due to the directions of the fibers;
• It can be a supporting support for the roof.

Frameless Walls

The first Nebraska buildings made of straw were unsupported thatched houses, in which the straw blocks themselves held the roof. Today they are called frameless structures - they continue to be built and this is allowed by building codes. Walls filled with straw blocks. In “Nebraska” type straw houses, straw is so compressed that it successfully withstands the construction of the house. The main structural load was performed by coupling the straw fibers protruding outward from both sides and a thick layer of clay stucco. Wide, densely laid straw blocks on one another and their coupling with clay or any other stucco mixture created the structure of the building. This pattern is similar to concrete reinforcement using different types of reinforcement or beams, only straw fibers stick out in all directions, which gives an even greater effect.

If there is a need to further increase the load-bearing capacity of the straw wall, then it is necessary to cover the straw with a net on one or both sides, and only then apply the stucco mixture. When using a metal mesh to crate the building outside, pay attention to the presence of rust and preferably cover the mesh protective coating, as it may begin to rust when in contact with wet plaster, which will subsequently lead to cracks in to the walls. Cement plaster requires a layer of at least 5 cm on the grill, so the mesh will be corroded inside the wall. When using clay coatings on the outside, the layer may be smaller. Inside the house, the humidity is much lower and you can do without such a number of precautions, except for naturally moist places, such as a bathtub, toilet and kitchen.

Frame walls

Another option for building walls is frame walls (post-beam frame), which is necessary to maintain the roof, windows, floors of the second floor and is often used in seismically active areas. According to this technology, the whole frame is first erected, including the roof, then this frame is filled with straw blocks, which perform only the insulation function in such a house. This type of wall has earned popularity because it is possible to carry out all thatched work “dry”, that is, under an already prepared roof, not paying attention to the weather.

In addition, such walls are fully consistent with building codes and do not raise questions in the United States and other countries of the world.

Combined walls

Some projects are carried out in a combination of these two techniques - straw walls and wooden supports at the corners and ridge of the roof. Such houses are called "hybrid" systems. The New Mexico State Building Code (reprinted in 1994) requires that all buildings and houses made of straw be built with a rigid frame, while in in other states, Building Codes allow for the construction of frameless houses based on a straw block (for example, California, Arizona, and others). There are states where there is no special section devoted to houses made of straw blocks.

In the case of building straw houses in such a state, it falls into the alternative technologies and materials section. In these cases, construction is allowed, both without a frame and with it. However, it is necessary to show the project of the house to a special engineer in the city services to obtain a building permit. Straw blocks are usually stacked like bricks in a checkerboard pattern. If it is necessary to reduce the size of the block, it can be divided in half or into large parts by re-tying the ropes. After they are laid in the wall, they easily pierce in the middle or on each side to connect the rows of folded blocks vertically. For this, bamboo, reed, reinforcement or wooden rods are often used. Usually, the future owners of the house with family and friends take up the work of laying straw into the walls. Such work can take one or two days off and it does not require special building skills. In the future, novice homeowners can continue to work on the crate and applying clay, thereby giving the house a unique look and making everything the way they intended. In addition, such work can greatly reduce the construction budget.

Curved walls

An example of a blank curved wall made of flat straw blocks (project: John Swiringen) “Curved walls are beautiful, their eyes rest and they create an interesting play of light. But they take a lot of time when you build them! I can build three flat walls in time and for the price of one curved.

In addition, you have to tinker with the foundation, supports, window openings and frames, and of course, with the roof structure. "(Straw block builder Frank Tettemmer from Life of the Sun") Pay attention to the quote above if you are really planning to build curved walls in your home. It will take more time and require additional skills. It will be necessary to carefully consider all the details: how will the pit fit under the foundation, what will be the structure at the roof, how to connect the foundation to the walls? In some cases, it is necessary to make supporting structures inside the house - additional supports. Perhaps in your case there will be more details that need to be taken into account. In the case of a smooth bending of the wall, straw blocks can be laid horizontally in the traditional way and shaped by pressing each block to the frame. In the case of a stronger bend, the blocks can be laid on the narrow side - vertically, rounding the wall due to the rotation of each subsequent block. Of course, it’s best to have the blocks in all walls in one way — either horizontally or vertically, but if in some places the structure requires laying the blocks vertically, then do it in the whole wall. Nevertheless, try to lay the blocks horizontally if your walls will carry out a constructive function and any weight will rest on them. Straw blocks retain their insulating characteristics - regardless of how they are laid. When you make round walls between the blocks, a gap forms on one side. The best way to fill this gap is to mix a large amount of straw with clay and hammer into the gap. Clay in this case will serve as an additional structural element.

If the net is beaten on top of the straw blocks, then in this way the risk of “jumping out" of the blocks outward under the pressure of the wall can be completely prevented. Another additional way to strengthen a round or curved wall can be belts stretched on the outside of the bend on each row of straw blocks. For fastening belts on each side of the wall, it is advisable to use wooden supports or slats. When reinforcing curved walls, it is important to remember that they are inherently more likely to tip over than any others. However, as a result, when using two methods of fastening - mesh (pulling together) and clay or plaster (compression), with Given the correct calculation of the geometry of the wall, you can get a very strong curved wall, which will only strengthen the strength of building. Walls of straw blocks - technical specifications, briefly.