So, we build, change or repair the floor, but the complexity is as follows: floor joists, the size of the timber.
What is the best material to buy? More on this later.
What it is
Lags for the floor are called timber, which performs supporting properties. Since the time of five-wall log cabins, floors were made according to the lag principle, but in those days, bars of a specific diameter replaced ordinary logs.
Now the logs for the new floor should be made of pine. And the best of them is larch. It is this breed that does not rot over the years, although antiseptics on the same pine increase the life of the material.
When buying timber from spruce or pine, it is important to monitor the humidity. If this value is below 20 percent in the material at the time of purchase, then the tree will definitely not lead. And this is a guarantee of a flat floor, even with amateur installation.
Cross section and dimensions
There are exact values for spans:
- No more than two meters, there is a section of 60x110 mm.
- For three meters you need a size of 80x150 mm.
- For four already 100x180 mm.
- Five meters require a material of serious strength, therefore a minimum of 150x200 mm.
- A span of six meters is the maximum, and we select the cross section, of course, the maximum 180x200 mm.
You also need to consider the distance when working with the floor. And it has the following features:
Installation: rules for different surfaces
Logs made of wood can be mounted on any type of bases, surfaces. But everyone is working now with wood, concrete and soil.
When laying on concrete, structures are necessarily created that help to level the common plane of the lag. And fasten wooden products with standard anchors or self-tapping screws. There is a possibility of collapse of the entire structure if you ignore part of the fasteners during the work.
It is important to know: when the logs are laid on the concrete of the first (basement) floor, then it is necessary to make waterproofing. For this, foil polyethylene films are used. This is very important, because a “neutral” is needed between different types of materials. It will ensure better preservation of the tree, reduce heat loss.
You can’t fix a tree on the ground just like that - the support is soft. Proceed as follows:
- Dig small holes (depth around 10 cm).
- Then they are sprinkled with sand and spilled with liquid.
- Polyethylene should be laid on top, and support pads for mounting are already created on top of such a pillow.
- Pillows are brick columns the size of the brick itself.
- A piece of roofing material is placed on top of each and installation is already underway.
- But you can’t attach logs to bricks, and it’s best to use galvanized corners to fix the overall structure to the walls.
And we will analyze the working moments with wooden beams as a basis. It is important to find out the moment of laying: transverse or longitudinal.
When the logs lie across the beam, it is easiest to fix them with standard self-tapping screws. Since we work only with wood, we take measures: we pre-drill holes for fasteners to avoid cracks.
Protect from rot
A large number of impregnations, stains and other antiseptic agents have been created to protect ordinary wood in conditions of high humidity.
And it is necessary to impregnate with such means individually each unit. It is recommended to leave a significant protective layer (from 5 to 15 mm) and use environmentally friendly types of impregnations.
In addition, when purchasing such a bar, pay attention to the dryness of the tree. Now there are devices that show the degree of moisture in any lumber.
Even before installation, you need to think over a plan for ventilation - this is the third important natural condition for protection against rot, mold and rodents. Floors should be blown with air cushions.
Lags are laid "on edge". This does not mean that the bars are actually fixed at an angle to spans.
No, the section helps to provide a margin of safety. It was invented only for this, well, and a little to save wood. So, the beam is laid on the floor with the side that is thinner. This is the main recommendation.
Before working with this material, it is necessary to calculate the length and section. But do not forget about the distance between them. When all values are selected correctly, as a result you will get a perfectly strong and even floor. Because the calculations are created so that there are no deflections under the furniture or creaking when a person moves.
