Fastening of the rafters to Mauerlat: Methods of connection

Attaching rafters to a mauerlat is essential to a roof structure’s longevity and stability. The mauerlat, sometimes referred to as a wall plate, is a horizontal beam that rests above a building’s walls. It functions as the main location where the rafters, which make up the roof’s structure, are attached.

Using metal connectors or brackets is a typical way to secure rafters to the mauerlat. These connectors are made to firmly secure the rafter in position and offer stability against loads on the roof and wind uplift. Usually placed at consistent intervals along the mauerlat’s length, they are secured with screws or nails.

Another traditional method is to join the rafters directly to the mauerlat using timber pegs or dowels. In order to create a sturdy, interlocking connection, wooden pegs are inserted through holes drilled through the rafter and the mauerlat. This method depends on the strength of wooden joinery. This approach is valued for its dependability and simplicity and has been used for centuries.

Certain contemporary building techniques, particularly in regions vulnerable to seismic activity or strong winds, may suggest that engineers use metal ties or straps to firmly fasten the rafters to the supporting walls and the mauerlat. In order to distribute forces uniformly and stop the roof structure from lifting or moving during severe weather events, these metal straps are frequently installed in a crisscross pattern.

The best way to fasten rafters to the mauerlat will depend on a number of variables, such as the building site’s unique conditions, structural requirements, and local building codes. Every approach has benefits and things to keep in mind, like how simple it is to install, how economical it is, and how resistant it is to environmental influences. Builders can add to the overall stability and safety of the roof structure by making sure that the rafters and mauerlat are securely fastened together.

Direct nailing: Rafters are nailed directly into the Mauerlat using large nails or bolts.
Metal connectors: Special metal brackets or straps secure rafters to the Mauerlat, enhancing stability.

"Securing rafters to the mauerlat is essential for maintaining the structural integrity and safety of roof constructions. This article examines a variety of connecting methods, ranging from conventional approaches like metal straps and bolts to contemporary choices like engineered metal connectors. Knowing these techniques increases the likelihood that roofs will successfully withstand loads and weather."

The main fasteners

A variety of handicrafts (sink) and metal rafter fasteners are used to install and securely fasten the rafter legs on the Mauerlat:

  • wire screed;
  • corners;
  • plates;
  • WB brackets;
  • Corner of the Kyrgyz Republic;
  • LK fasteners;
  • self -tapping screws;
  • nails;
  • perforated mounting summer TM;
  • Bolts, studs complete with nuts and washers.

Brackets are an effective way to join the rafters and the Mauerlat. Since there isn’t an inspection in this instance, the structure’s main structural component is not compromised. The steel used to make installation brackets has a zinc coating that prevents corrosion and is 0.2 mm thick. Using self-tapping screws, anchor bolts, or nails, the brackets are fastened to the wooden beam and rafter.

Raffers can connect to other system components and Mauerlat thanks to LC fasteners. There is no need to use anchor bolts when installing this fastener.

You can improve the connection node by using a perforated mounting tape. Since the perforated tape does not compromise the integrity of the supporting structures, it strengthens the connection between the rafters and the Mauerlat. To install it, self-tapping screws or nails are needed.

One of the most requested fastening components for the rafter system is the corner of the Kyrgyz Republic and its modification. If necessary, it is used to install rafter legs on the Mauerlat with reliability.

The corner strengthens the compound nodes, improves the structure’s supporting qualities, and prevents rafterin displacement during heavy operation loads. The corner of the rafter system does not need to be cut; instead, it can be fastened with dangerous nails or self-tapping screws (which have ledges installed).

The strength and longevity of the metal fasteners used in the rafter system are ensured when they are composed of premium materials with dependable anti-corrosion protection.

In what cases is Mauerlat required?

Mauerlat is frequently referred to as the roof’s foundation. With its log or timber design, the rafters can be fixed firmly and the loads on the walls and foundation of the building can be evenly distributed.

When building a house out of a beam or log, the rafters serve as support for the walls’ upper binding; additional structures do not need to be installed.

Mauerlat installation is required for structures whose walls are composed of piece materials (brick, foam concrete, aerated concrete blocks, etc. D).

This is because these kinds of walls struggle to support point and retained loads. Furthermore, foamed material blocks are not robust enough to securely fix the rafter system; fasteners may rip out of the unit when under load. Mauerlat installation is therefore necessary.

Pre-creating a reinforced concrete belt in the upper part of the walls is advised in order to ensure that a wooden beam laid on the building’s longitudinal walls or along the entire perimeter (depending on the type of roof) is securely fastened to the base. Fasteners for the support beam are installed in a monolithic beam that is 200 mm high and has a width equal to the wall’s width.

These are 14 mm-diameter anchor bolts or studs that are positioned only vertically. The lower ends of the studs or bolts should be bent to eliminate the possibility of them tearing from concrete under a heavy load. The embedded fastener can be found with a maximum step of 1.5 meters.

Use of studs smaller than 14 mm in diameter may result in strain deformation when loads are applied.

Holes that match the location should be drilled in the beam that holds the Mauerlat. The beam is positioned on stilettos, washers are placed on the fasteners’ free threaded ends, and nuts are tightened. You can firmly fasten the roof’s base to the wall with the help of this technology.

It is imperative to apply the waterproofing layer prior to beam installation in order to guard against moisture-induced damage to wood.

Principles of fastening rafters to Mauerlat

Building spacer and sprayed rafter structures may necessitate installing rafters on a support beam. A sliding or hard connection is used to install hanging or layered rafters on the Mauerlat. The techniques used to fasten rafters to Mauerlat are chosen based on the characteristics of the structure.

To prevent reducing the rafter leg’s bearing capacity, jerking should be done there rather than on Mauerlat.

A rigid connection indicates that all elemental displacements with respect to one another are completely excluded, as are any influences like shift, torsion, or bending. If the rafters to the Mauerlat are fastened with corners using a support bar, or if a unique neckline is made in the rafter leg, the required stiffness of the connection is guaranteed. In addition, brackets, bolts, screws, and nails are used to secure the cutting location in the rafter. In order to connect the rafters’ mounting unit with Mauerlat and an anchor set into the wall, wire twisting is also required.

A unique fastener known as a "slide" is used when building a wooden house’s roof; it enables you to make a sliding connection. When reducing the size of the house from a beam or log, the roof deformation can be prevented thanks to the way the rafters are knotted to the Mauerlat with a certain amount of rafter freedom.

Installation of rafters using a corner

It is vital to start with the structural elements of the roof when deciding how to attach the rafters to Mauerlat. Should we not be discussing wooden structures, then the joint ought to be robust.

The following work technology will be used if the rafters are installed using a clipping "saddle":

  • The cutout is performed in the rafter leg so that the horizontal part of the rafters can be installed on a wooden beam, while the angle of inclination of the rafter leg must correspond to the angle of inclination of the slope;
  • The rafter is fixed by three nails, two of which are driven on both sides of the rafter leg at an angle (crossing should occur inside the Mauerlat), and the third nail is driven vertically from above;
  • Additionally, the mounting node is fixed with brackets, roller wire.

The rafters’ attachment to the Mauerlat gives the node the required rigidity and strength.

The installation of rafters using a bearing beam and a metal corner is a fairly common technique. The rafter attachment is as follows:

  • The rafter leg is cut at the required angle to ensure the slope of the roof slope set by the project;
  • On the edge of the Mauerlat, a bearded beam is mounted, the length of which is about 1 meter, the rafter is strictly rested on it along the pressure line – this design eliminates the shift of the rafter leg under the load on the spacer;
  • On the sides of the rafters should be attached to the Mauerlat with the help of metal corners – the fasteners of the rafters to the Mauerlat with these elements make it possible to avoid the transverse displacement of the rafter leg;
  • The finished mounting node is additionally enhanced by a roller wire.

The video provides information on the specifics of the work technology and should be followed when constructing the rafters of the Mauerlat.

Utilizing unique corners, the rafters are fastened to the wooden support beam. The following are some of the KR’s subspecies:

  • Models KR11 and 21 (improved KR1 and KR2) are equipped with oval openings for survey, which can significantly reduce the risk of a breakthrough of the mounting element during the precipitation of the building or the load load;
  • The KR5 model allows you to attach structural elements with great bearing capacity;
  • The KR 6 (reinforced corner) model is made of 3 mm steel, has an oval opening for survey, used to install structures with a large weight.

The perforated steel KM mounting corner is also used to attach the auxiliary and supporting elements of a wooden rafter structure. Self-tapping screws and screws for fastening are among its benefits, as is the absence of special equipment required for installation.

Use of the improved KMRP corner is limited to compounds at a 90° angle. You can install wooden rafters on a support beam with reliability if you use it. It is possible to adjust the corner.

In summary, the stability and longevity of your roof structure depend on the technique you use to secure rafters to a mauerlat. Every technique mentioned, including the use of bolts, metal connectors, and conventional timber joints, has a special benefit depending on the structural requirements, cost, and ease of installation.

Take into account the particular requirements of your project when choosing the best course of action. Which technique will guarantee the strongest and longest-lasting connection depends on a number of factors, including environmental factors, roof design, and local building codes.

Furthermore, traditional techniques like dovetail joints or mortise and tenon joints appeal to individuals seeking a balance between structural integrity and craftsmanship, even though contemporary metal connectors offer strong support and ease of installation.

Ultimately, making sure that the connection between rafters and mauerlat is sturdy and secure is crucial for a long-lasting, safe roof, regardless of whether you choose the practicality of bolts and metal connectors or the age-old charm of timber joints.

Video on the topic

Mauerlat attachment nodes, proper installation of the roof of the house with your own hands, installation, connection

What do you think, which element is the most important for a reliable and durable roof?
Share to friends
Alexander Sorokin

The owner of the roofing company, an expert in the roofing markets. I'll tell you about the novelties of the roofing industry and help you choose the best option for your home.

Rate author
Add a comment