When constructing a home or any other structure featuring a pitched roof, the word "Mauerlat" may be encountered. Although this component has a technical name, once you understand its purpose, it becomes fairly simple to use. To put it simply, a Mauerlat is an essential component of the roof framework that works to evenly distribute the weight of the roof onto the building’s walls.
Consider the Mauerlat as a robust horizontal beam supported by the walls. Its primary responsibility is to make sure that no one area is overly stressed by the weight of the roof. The Mauerlat helps avoid structural problems that could result from an uneven load by distributing the weight evenly.
The rafters, or angled beams that support the roof itself, rely on the Mauerlat, which is usually made of metal or wood, as their foundation. It’s a crucial component that guarantees the longevity and stability of your roof. Without it, the entire roofing system might be in danger, particularly in situations with lots of snow or wind.
You can appreciate the design and engineering that go into creating a sturdy and safe roof better if you know what a Mauerlat is and how it operates. The next time you hear the term, you’ll know that it refers to a crucial component that keeps your house safe and sound rather than just technical speak.
Term | Description |
Mauerlat | A wooden beam placed on the top of the building"s walls to support the roof structure and distribute its weight evenly. |
Purpose | To provide a stable base for attaching roof rafters and to prevent the roof from shifting or collapsing. |
Materials | Typically made of strong, durable wood like oak or pine. |
Installation | Secured to the top of the walls using metal brackets, bolts, or anchors. |
Importance | Crucial for ensuring the stability and longevity of the roof, especially in areas with strong winds or heavy snow loads. |
- Mauerlat – what is it?
- Profile, sizes of Mauerlat and factors that affect them
- Mauerlat for the roof – how to fix the rafter beams
- Necessary tools and materials used
- How to fix a roof Mauerlat to a wall
- Features of rigid fixation
- Hinged fastening method
- How to make a Mauerlat yourself
- Video on the topic
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Mauerlat – what is it?
Professional builders frequently refer to a power frame that runs along the upper contour of the structure’s supporting walls as "Mauerlats" in their terminology. Beginners and do-it-yourself artisans who haven’t run into major construction issues might find the questions of its size, purpose, and installation techniques perplexing. Let’s investigate it in more detail.
A support frame that functions as a damping element is called mauerlat.
It is composed of the following materials and is situated outside the main walls’ end plane:
- rolled steel;
- wooden beams.
In addition to distributing loads evenly along the walls’ perimeter and securely fastening the roof trusses to the walls, the Mauerlat joins the building frame and roof trusses in a closed power circuit.
The supporting structure’s primary objective is:
- strong fixation of roof truss elements to main walls;
- reducing the magnitude of thrust loads transmitted to the building frame;
- uniform distribution of forces from the rafters to the upper plane of the walls;
- compensation of locally acting loads at the junctions of elements.
On the upper tier of the masonry, different loads act:
- angled thrust forces of the roof rafters, trying to cause the destruction of the building frame;
- vertically directed loads from the weight of the roof and the mass of snow on it.
By sensing the load, the power structure maintains the masonry’s integrity and provides dependable roof fixation. Particularly pertinent is Mauerlat for a roof supported by foam block walls, aerated concrete, and brick.
Profile, sizes of Mauerlat and factors that affect them
When building a support frame, most builders utilize wood rather than steel profiles. This can be attributed to the material’s accessibility, decreased weight, processing simplicity, fastening simplicity, and reasonable cost.
Balks of various profiles are used:
- square;
- rectangular.
Cross-section configuration makes installation easier and offers more stability.
The weight and form of the roof as well as its design dictate the dimensions of the frame’s cross section. Specific varieties are utilized:
- 10×10 cm – for small buildings;
- 10×15 cm – for gable roofs;
- 15×15 cm – for loaded rafter farms;
- 25×25 cm – for massive attic structures.
The following criteria are used to determine the support beams’ dimensions:
- size of the building box;
- design features of the roof;
- weight of the roofing system;
- rafter material;
- climatic operating conditions;
- presence of an attic floor.
Rectangular beams with a larger area of the supporting surface must be used when the weight from the roof of a complex structure increases.
Mauerlat for the roof – how to fix the rafter beams
There are several ways to connect rafters to support bars. The following resources are employed:
- metal corners. They are screwed with self-tapping screws from opposite sides of the rafters, and provide a reliable connection with the power frame;
- annealed wire. Using soft steel wire with a diameter of 6 mm, it is easy to twist the connected elements of the rafter structure;
- curved brackets. The fasteners have a U-shaped configuration. Fixing is carried out with a hammer by driving a bracket into the support beam and rafter;
- steel plates. Provides a reliable connection of metal rafters. Screwed with threaded rods or self-tapping screws;
- special brackets. Purchased and homemade brackets made of 2–2.5 mm thick metal are used. Attached with anchors or self-tapping screws;
- mounting tape. It provides increased rigidity of the connection. Does not weaken the load-bearing structure at the attachment points.
Each unique connection method is chosen with consideration for the building’s design elements and materials.
Necessary tools and materials used
You will need a tool that most do-it-yourselfers have in their toolbox to complete the task:
- angle grinder with discs for working on steel and wood;
- screwdriver or electric drill with a set of drills;
- hacksaw for wood to make connecting grooves;
- hammer;
- building level and tape measure for control measurements;
- pliers.
List of components used:
- dried timber beams;
- waterproofing material;
- fasteners.
Depending on the fixing technique chosen, fastening can be completed using:
- nails;
- self-tapping screws;
- screws;
- annealed wire;
- anchor bolts;
- threaded studs;
- steel plates.
The size of the building on which the roof Mauerlat is being built determines the amount of materials required.
As a horizontal beam that rests atop a building’s walls to support the weight of the roof, a mauerlat is an essential part of construction. In essence, it shifts the weight from the roof structure to the walls, assisting in the uniform distribution of the mass and maintaining structural integrity. Said another way, it functions as a solid foundation that prevents the roof from collapsing onto the walls, guaranteeing the stability and strength of the entire structure.
How to fix a roof Mauerlat to a wall
There are several ways to secure the Mauerlat along the upper tier of the box’s contour:
- steel wire. To increase the reliability of the fastening, a wire with a cross-section of 5–6 mm is repeatedly twisted and fastened in the depth of the masonry. After the binder solution used for the construction of the walls has hardened, the protruding parts of the wire loop are inserted into the holes of the frame and carefully twisted. In places where the ligaments are attached, the beam is firmly pressed against the upper plane of the box. It is important to choose the right length of wire, sufficient to completely cover the beam. Advantages of wire connection – low cost and ease of fixation;
- metal anchors. They are attached to the steel frame before pouring the reinforced belt with concrete mortar. After the concrete has hardened, the beam is placed on the threaded parts of the anchors through holes of the appropriate diameter. It is important to correctly mark the coordinates of the fasteners to match the holes with the anchor fastening. The beam is fixed by tightening the nuts. Advantages of the anchor connection method – increased reliability. Disadvantage – increased cost compared to wire fastening;
- special studs. They are bent at a right angle and have a thread on one side. A bent end with a smooth surface 40-45 cm long is fixed in the masonry during its construction. The top of the threaded part of the stud is located at a distance of 30–40 cm from the top edge of the main wall. The length of the stud body allows you to secure the beam due to the protrusion of the threaded part above the frame level by 30-40 mm. The fixation method is similar to the method of connecting using anchors. When concreting threaded studs in masonry, protect the threaded part from clogging.
Apply a waterproofing coating to the load-bearing walls’ supporting surface prior to beginning the process of fastening the support beam.
Features of rigid fixation
Rigid fixation of rafters to support frame beams is a technique used for roof installation on capital buildings made of concrete or brick. The unique feature of rigid fixation is that it keeps the rafter frame from shifting in any direction.
Use rigid fixation in the manner described below:
- Prepare a landing pad at the junction of the beams.
- Align the beams of the roof truss with the support beam along the saddle groove.
- Fix the rafters with nails, driving them in at an angle from different sides.
Make sure there are no distortions and that the seat is flat before cutting a connecting groove. The connection will be more reliable if self-tapping screws are used to fasten steel corners on opposing sides of the rafter elements.
Hinged fastening method
A wooden building’s walls are always distorted in situations with fluctuating humidity and temperature. When the house’s walls shrink, the hinged fastening technique keeps the roof from skewing. For prefabricated panel houses or log buildings, the sliding fixation method is employed. Because the fastening unit can slide, the roof position doesn’t change when the wall is lowered. The technology is applied on problematic soils and in humid climates.
There are several varieties of hinged fasteners in use.
- open design. Includes guide plates attached to the rafter beams, as well as corners screwed with self-tapping screws to the wall plate. An open-type joint has a degree of freedom that allows the connected elements to move in the range from 6 to 16 cm;
- closed unit. The connecting block of a closed design is not disassembled and is installed assembled. The principle of its operation is similar to the operation of an open fastening. The stroke of the connected elements is determined by the design of the closed fastening.
You should be aware of the following when following the sliding fastening instructions:
- the location of the rafters, the extreme part of which should extend beyond the contour of the building box;
- equal length of the rafter beams, significantly reducing the time for fitting and installation;
- parallelism of the rafters, due to which jamming of the sliding fastening is prevented.
The smooth functioning of the sliding mechanism is guaranteed by the accurate geometry of the roof truss.
How to make a Mauerlat yourself
It’s critical to mount the beams correctly and guarantee a solid connection between the elements in order to guarantee the dependability of the fastening.
Let’s look at the steps involved in mounting a wall plate constructed from a wooden beam with a square profile:
- Thoroughly clean the upper surface of the load-bearing walls from debris and mortar build-up.
- Lay a double waterproofing layer of polyethylene film or roofing felt.
- Cut the support beam into pieces, the total length of which corresponds to the perimeter of the box.
- Cut the corner areas of the joint, as well as the end plane in the places where the timber is built up.
- Apply an antiseptic composition to the surface of the wood and treat it with fire-prevention impregnation.
- Mark the rafter attachment points using a tape measure or a template in the form of a regular board.
- Drill holes in the beam, ensuring they are perpendicular to the supporting surface.
- Connect the beams of the support frame using threaded connections, an oblique cut or self-tapping screws.
- Reinforce perpendicular beams with metal plates or special brackets.
- Attach Mauerlat for the roof to the upper tier of capital walls using the selected fixation method.
- Check the correct positioning of the supporting structure and the absence of distortions using a level.
Linings can be used to remove minor distortions if needed. Any preferred method can be used to easily attach rafter beams to a Mauerlat that has been firmly fastened.
All things considered, the Mauerlat is essential to the construction of any building, especially for supporting the roof structure. It serves as a connecting piece for the roof and walls, distributing weight evenly and guaranteeing the stability of the entire construction. The Mauerlat aids in preventing movement or shifting by fastening the roof trusses or rafters to the walls. This can be vital for preserving the structural integrity of the building over time.
Knowing how the Mauerlat works will also help you to understand why installing it correctly is so important. Inadequate installation of the Mauerlat can result in structural issues like drooping roofs or even wall damage. Thus, the secret to constructing a structure that is both safe and long-lasting is to make sure that this component is positioned correctly and fastened securely.
In the end, even though a building’s Mauerlat may not be the most visible component, it plays a crucial role in the entire structural system. When done correctly, it supports not just the roof but the building’s entire structure, which makes it a crucial component of building projects. Thus, understanding the Mauerlat helps anyone, whether they are building professionals, homeowners, or simply interested in construction, to better understand how various building components interact to guarantee a structure’s durability and safety.