Ceiling girders: installation and disassembly. And the question: buy them or rent them?

No matter what kind of ceiling you choose, whether of prefabricated elements or monolithic reinforced concrete, girders, commonly known as construction docks or joists, are necessary for its installation. From what materials the beams are made? How is the installation of girders and their disassembly?

And finally: whether it is better to opt for renting girders or buying them?

Any construction project is a huge undertaking, a time-consuming and multifaceted process that requires multiple operations, adequate organizational and logistical preparation. In the end, each element is important both for the appearance of the building and the safety of use. One of the most important parts of any building is the ceiling, which is the horizontal structural element that separates the successive floors of the building from each other, but also, with proper preparation, it can become a flat roof. The task of the footing is to provide adequate insulation of the rooms on each floor, thermal and acoustic. However, one of the most important parameters is its strength, since it must carry significant loads.

The strength also determines the span of the ceiling, that is, the size of a given room without columns and joists.

No matter what kind of ceiling you choose, whether of prefabricated elements or monolithic reinforced concrete, to install it it is necessary to use girders, Commonly referred to as construction docks or joists. As in any industry, it is worth making sure that they are of good quality because the safety of people working on the site also depends on it. Proven brands are, for example.

Peri, Doka or Boguc Construction girder.

Beam is a load-bearing element used in construction. It is the main horizontal support of the structure, which supports smaller beams. Girders often have an I-beam cross-section composed of two load-bearing chords separated by a stabilizing web, but they can also have a closed shape, a Z-shape or other forms. So much for the dry definition. And what the girder is actually used for?

Let’s look at its types and applications in industrial and residential construction.

The task of the construction dock is to support and fix the floor formwork In a vertical or oblique position. Formwork is a form into which concrete is poured , to give it the intended shape. Depending on the manufacturer, formwork may vary, but there are several universal elements.

One of them is the formwork slab, which holds the poured concrete. The most commonly used for this is waterproof plywood from poplar or birch trees. It is characterized by tensile and bending resistance.

It is a reusable product, easy to install and relatively lightweight.

The second element of the formwork is The girder, which supports the plywood along with the concrete at the correct height and at the right angle, until the mixture solidifies. Since it is a heavy structure, it is important that it is properly protected against slipping or collapse. Thus, on the girders depends the quality of the erected structure and safety.

What materials are made of girders?

Depending on the purpose, it is used Beams made of metal or wood. For ceilings, walls and columns, wooden girders are most often chosen because of their light weight. It greatly facilitates their installation and handling of such elements.

The girders are manufactured Of softwood, usually pine, fir or spruce. This type of wood is characterized by high strength and flexibility. It should be a strictly selected material from sustainable cultivation.

In order to extend the life of construction docks, various treatments are used. First They are coated with waterproof paint and anti-fungal agents. It protects the element from rotting, cracking and increases resistance to changing weather conditions.

In addition, there are also beams available on the market, the ends of which are covered with plastic with shock-absorbing properties. This protects the beam from mechanical damage.

Universal wooden formwork girder with an overall height of 20 cm, and a width of 8 cm, is available in many lengths. This makes it easier to match the project.

Installation of girders

Thus prepared girder should be installed. How it is made, what the entire structure consists of?

The basis is the building support (skewer), on which all elements of the structure are supported. The strength of the entire formwork system depends on the skewers. In addition to supporting girders, they are also suitable for supporting lintels or balconies.

Telescopic construction of building supports and a large selection of dimensions, allows you to accurately adjust the height relative to the design assumptions. In order to increase the stability of the support, and to protect it from falling over, it should be supported by a construction tripod, this will significantly increase safety during formwork work. It is assumed that on a construction site the ratio of supports supported by tripods to those unsupported should be 1:3.

The flexibility of the product means that it can be set at any angle, allowing them to be placed against walls and in corners.

On the top of the support, by inserting a pin, the head is mounted. The spacing of the bars, or angles (depends on the type of head chosen, also known as the construction crown) allows the girder to be stably positioned. A major advantage is that the head can be rotated by 90 degrees, making it possible to place two girders in parallel.

In this way it is possible to connect beams in any length, without the need for additional supports.

Now you need to install the girders, which requires proper adjustment of the height of the supports along with the previously installed heads. The supports should then be arranged to support the ends of the girders, or where there will be a connection between them. When everything is ready, you can start installing the girders on the heads.

The girders must be properly leveled and secured against movement.

The girders (Boguc Construction) can be installed both manually and using specialized equipment. Manual assembly involves the use of appropriate tools and is often used on smaller construction sites or with limited access to specialized equipment. On the other hand, installation with specialized equipment involves the use of cranes, cranes or jacks, to position and bolt the girders to the supports.

This method of installation is often used on larger construction sites, where the use of manual equipment would be difficult or impossible.

Disassembly of girders

The formwork should be started when the concrete reaches min. 70% of its ultimate strength. Then the whole structure is stable enough that it should not be damaged. It is worth noting that this parameter applies not only to ceilings, but also to walls, columns and other structures.

Too early disassembly can lead to deformation, to cracking of the concrete, which clearly weakens its durability, and in extreme cases can cause the collapse of the entire structure. Thus, if the construction is to be durable and free of defects, it is necessary to observe the holding time of the formwork.

During formwork stripping, it is necessary to follow certain rules. First of all, lower the supports. This is possible due to the rapid lowering mechanism used. This mechanism allows the formwork to be lowered, making it possible to remove the girders safely, without damaging them. To perform this task, it is necessary to use a mounting fork.

The next step is to disconnect the three-legged support stands.

Concrete formwork is very susceptible to dirt, so it is worth cleaning it with professional products designed for this purpose. The elements prepared in this way should be placed on specially prepared pallets and transport baskets.

The type of wooden floor girder discussed here is the most common, but it is worth remembering that it is not the only one. Depending on the structure being erected, we also distinguish between a girder as a structural element (e.g. roof truss) and as a part of the structure (bridge girder, which is usually a bridge span). Each girder is designed to transfer the load of the structure to the main supports such as the. walls, columns or pillars.

Buying new or used girders? How about renting?

This question generates a lot of discussion and many contractors scramble to decide whether it is better to buy or rent. Some contractors are strongly opposed to renting equipment, arguing that rent is “dead money,” while purchased equipment not only meets operational needs, but also adds a valuable resource to the company. Other contractors believe that the rental option offers a more flexible and less risky option than purchasing, which ties up large amounts of capital and puts a strain on cash flow.

Buying equipment usually makes sense if there is a continuous demand that lasts for a significant period of time. Most industry experts suggest that If the equipment is needed for 9 months or longer, it is more cost-effective to purchase, Than its lease. However, this should not be the only deciding factor.

Buying new formwork or only its components, including girders, involves a large financial outlay, and high initial costs can have a negative impact on working capital, which in turn can have disastrous consequences.

On the other hand, by buying the right, good-quality equipment, the company gains assets and resources. You can also consider buying used girders. If they are properly stored and refurbished, they should serve us for many more years, and the acquisition cost will be much lower.

Equipment gives the contractor the ability to actually get the job done, and given the long-term savings, it should help the contractor be both more profitable and competitive in tenders. With a large investment, contractors always risk that the market situation will deteriorate, but there is a high demand for good quality used equipment worldwide, and the contractor can easily sell his girders.

On the other hand, we live in a world of ever-increasing accessibility and choice, where the sharing economy makes it possible to share resources by renting them out. Such assets include various sectors: electronics, automotive, apparel and just construction. There are also platforms where you can rent the necessary formwork elements or scaffolding. In other words, we live in a world where asset ownership is less and less important, and value is more about being able to use the right product at the right time and only for the time it is needed. For example, at Boguc Construction, the girders can be leased with delivery to the construction site for a specific period of time and there is no need to incur the cost of purchasing them.

However, in a situation where someone prefers to buy the girders after the construction is completed, he can change his mind and nevertheless sell them in the same company. Nowadays, there are as many opportunities as there are needs and the construction market is very flexible.