How to fix logs to concrete floor

Wooden floors considered the best finish. It is environmentally friendly and warm material. But the installation of such floors on a concrete base is associated with certain difficulties. In order to technologically correctly perform this process, preliminary fixing of the log to the concrete floor is necessary. It is not recommended to lay wooden floors immediately on a concrete screed. Using lag as additional elements it provides ventilation of floors and optimizes heat transfer in the apartment. Accordingly, the flooring will last much longer. Fixing the structure to the concrete floor is a simple process and does not require special knowledge and skills. We will familiarize you with all the subtleties of performing these works.

Preparation of materials and tools

Before starting work, you need to stock up on everything you need. Given that you have to work with wood and concrete, the list of necessary tools will be as follows:

• pencil;
• building level;
• roulette;
• hammer drill;
• woodworking devices (planer, hacksaw or circular saw);
• a screwdriver or a set of screwdrivers;
• fasteners (usually self-tapping screws, dowels and anchor bolts).

Having prepared the tools, you can go to the nearest construction market for material. Usually, sellers of lumber, in pursuit of personal profit, are advised to purchase expensive varieties of wood, referring to the reliability and long service life of the material. No need to fall for this trick. Spruce, fir and pine may well be suitable for your purposes. Varieties of wood of category B or BC are quite suitable, the moisture content of the material should not exceed 18-20%. At the same time, the appearance, color and even evenness of the details do not play a big role. The only thing you should pay attention to is the absence of mold and traces of the bark beetle.

The lag section depends on the thickness of the flooring and insulation. Experts do not recommend using a beam with a cross section of less than 20 millimeters as a log.

Installation process

Immediately it is worth clarifying that the use of lag under the floors is advisable only in apartments with high ceilings. This technology of floor installation pretty much “steals” the height of the premises. So, the installation of the lag occurs according to the following scheme:

• Screed or the concrete base is recommended to level. Otherwise, the elements will not be in the same horizontal plane. Accordingly, they will need to be aligned by inserting plates. This can lead to the fact that the floors in the apartment will creak.
• On the base you need to lay a layer waterproofing, or treat concrete with special mastic. In the first case, the use of soft materials should be avoided. Over time, they will sink, and the floor will no longer be reliable and monolithic. For the waterproofing layer, roofing material or a plastic film is perfect.
• Logs are treated with an antiseptic composition and are cut according to the size of the room.
• The installation process begins with the installation of a lag at two opposite walls. These elements are aligned using the building level and are immediately fixed to the concrete floor. Then between the established lags a string is stretched. It will serve as a guide for the installation of the remaining elements.

• The remaining lags are stacked. The distance between the elements depends on the thickness of the future. flooring.
• Between the lags a heater is filled up. Ecowool or roll materials can be used for this. In the second case, you need to mount the material as densely as possible without leaving gaps between the layers.
• A layer of vapor barrier spreads. This is a necessary condition for protecting the insulation from external influences. The vapor barrier can be attached with a stapler, the joints need to be glued with tape.
• You can lay a layer of plywood. This will serve as the basis for the installation of flooring.

The distance between the structural elements

In order for the floors to last for a long time, it is necessary to strictly observe the step between the laid parts. You can use the table for this.

When laying plywood bases on the logs, the distance between the elements can be increased.

Ways to install lag

There are four ways to install the log on a concrete base. After reviewing the above material, you can choose the best option for you.

Screws

This mounting scheme is considered the simplest and fastest. It looks like this: lags are laid in place and drilled through. Note that the drill must go through the wood and go deeper into the concrete coating. A dowel is driven into the hole and a self-tapping screw is twisted.

The recommended distance between fasteners can vary from 40 to 80 centimeters. The length of the fastener depends on the thickness of the log. Note that the self-tapping screw must go into the concrete no less than 50 mm. For better adhesion of the lag to the surface, it is recommended to use self-tapping screws with a thread not reaching the hat.

Anchors

This method is used not only for fastening elements, but also to give the structure additional strength. Pulling the anchor out of the concrete base is quite problematic, so it can be difficult to dismantle such a structure. Anchors are installed, like self-tapping screws, by drilling through holes. A locking element is inserted into the concrete, into which the bolt itself is screwed through the lag. To the head of the bolt "drowned" in the wood, the holes must first be countersinked.

In the process, it is recommended to use anchor bolts with a diameter of about 10 mm. The length is selected individually, taking into account the bolt entering the concrete by 5-6 cm. For fastening one log you will need 4-5 anchors.

Metal corner

Another way to install wooden elements on a concrete base. To do this, you will need a galvanized metal corner. The installation process looks like this: the corner is attached to the log with a self-tapping screw (the fastener must go into the tree at least 3 cm). Then, with a screw through the dowel, the corner is attached to the concrete coating.

Adjustable lags

This is the most expensive design, greatly simplifying the alignment of elements in the horizontal plane. It looks like this: plastic stands are built into wooden elements, which, in turn, are attached to the base of the floor. Alignment takes place with the help of an adjusting bolt. Using this design will allow you to perform work without prior alignment of the screed.