The subject of this article is a laminated timber bath. We have to find out if this material is different in terms of construction from alternatives; does he need interior cladding and insulation; finally, on what foundation is it better to build a bath.
So let's get started.
The general principles of laying foundations were formulated long ago:
- The shallow foundations are used on stable soils. The pressure on the ground should not exceed the carrying capacity of the soil at the construction site.
- Fluffy soils make lay the foundation below the freezing point. Otherwise, swelling of the freezing soil may cause deformation of the walls of the building.
However, houses and baths of laminated veneer lumber (as, indeed, all wooden structures) are distinguished by their low weight. With sufficient rigidity of the foundation, it, even being laid at a shallow depth, will transfer the swelling of the soil without damage: in fact, the tape base will become so-called floating.
In addition: the bath and the house of laminated veneer lumber can easily transfer minor shifts of the foundation without damage due to the strength of the walls, where the crowns are reliably connected to each other.
From here - types of the bases applied at construction:
- The shallow belt tape has a maximum bearing capacity and can be used on unstable soils. It distributes the mass of the house over the ground surface as evenly as possible.
- The columnar foundation is used on flat areas with non-refractory soils. The price of this foundation is minimal; building it yourself is more than easy and comes down to building brick columns 40-70 cm high on a sand bed.
- Screw piles are remarkable in that they allow the mass of the structure to be transferred from the upper soil layers (black earth or plastic clay) to more dense lower ones. What is especially nice is that the device of the screw foundation for a bar-shaped bath does not require excavation work on its own hands and is possible in areas with a large slope.
Do projects of a laminated timber bath differ from projects involving the use of solid material?
There is no practical difference for the builder at the wall construction stage.
The advantages of laminated veneer lumber appear somewhat later:
- The change in the volume of timber for the entire lifetime does not exceed 1 percent. As a result, after the erection of a bar-shaped bath, a long wait for shrinkage of the walls is not required. All construction, including the installation of windows and doors, can be done in one go.
- Fire resistance is much higher than that of solid wood constructions. For the bath is a significant advantage.
- Deformation of the walls with fluctuations in humidity can not be afraid. Glued laminated timber perfectly keeps its shape.
- The appearance of through cracks through which heat evaporates is impossible. Glue joints in the beam prevent the spread of cracks from the lamella to the lamella; their vertical position limits the maximum depth of one crack to 1/3 - 1/5 of the wall thickness.
A nice bonus is the quality of the surface of the bar. It is not inferior to furniture, which allows you to use the texture of wood as an element of room design.
Is the glued timber for the bath unconditionally suitable? Frightened by horror stories about phenol-formaldehyde and styrene, the reader cannot help but wonder about safety. Will the material release harmful substances when heated?
No, you can not worry about health.
There are several reasons for this.
- Полиуретановые и меламиновые клеи, применяющиеся при производстве бруса, не относятся к токсичным. К примеру, смертельная доза меламина для крысы составляет больше трех граммов на килограмм ее собственного веса. Примерно такой же степенью токсичности обладает… поваренная соль.
- The glue content as a percentage of the total weight of the timber is negligible compared to common OSB and particleboard.
- Glue joints are located inside the timber and are not in contact with the air inside or outside the room.
Facing and warming
Should the project of a laminated timber bath include interior lining and additional insulation?
The problem has more than one side.
Let's try to weigh the arguments and counterarguments.
- Insulation and wall paneling will increase the already rather big cost of a log house.
- Facing and warming уменьшат полезную площадь парилки. Когда речь идет об объеме в единицы кубометров, толщина утеплителя и вагонки уже не кажутся пренебрежимо малыми.
- On the other hand, a wooden wall with a thickness of 10-15 centimeters has relatively low thermal insulation qualities. Insulation of 10 cm thickness will improve them at least twice.
Note: heat loss with a fixed thermal resistance of the building envelope is directly proportional to the temperature difference with the street. It is clear that a steam room with a temperature of a hundred degrees will lose much more thermal energy than a residential house with its 20-25C.
- Finally, most of the laminated veneer lumber in our country is made of spruce and pine. These types of wood are not only hygroscopic, but also subject to rotting. Yes, antiseptic impregnations partly solve the problem; however, they will inevitably be washed out in a hot, humid room. In addition, due to changes in temperature and humidity, the inner surface of the timber will quickly lose its original luster.
- Finally, spruce and pine - resinous rocks. When heated, they will inevitably soil visitors to the steam room.
Traditionally, the instruction for wall insulation looks like this:
- With a wall thickness of 200 millimeters and more, the bath does not need additional insulation. Facing from the inside, if done, it is only to protect the walls from moisture.
- With a smaller thickness, the bath is insulated with a layer of mineral wool of 100-150 millimeters.
Let's formulate the conditions that must be met by warming and cladding.
- A house with a bath of laminated veneer lumber insulated in fundamentally different ways. If the wooden house is insulated from the outside, and the insulation is vapor-permeable, then in the bath the internal lining should be separated from the internal insulation of the walls by a vapor-proof material. Otherwise, under the warming of the timber, the walls will start to rot, and the efficiency of thermal insulation will sharply decrease.
- As a lining is used, as a rule, lining of rotting resistant wood species with minimal thermal conductivity. A typical solution is linden, which retains the original appearance and characteristic aroma for a long time.
- Lining should be ventilated - both from the front and from the back. Gaps are required between it and the vapor barrier.
- Insulation and vapor barrier should transfer heat to 100-120 degrees without deformation, changes in physical and chemical properties.
How to achieve the fulfillment of all the listed conditions?
- The crate perpendicular to the lining direction is stuffed on the walls. The distance between the side surfaces - 59 centimeters.
- Basalt wool mats are installed between the bars of the crate and the grating.
- Insulation overlapped with vapor barrier film or, which is much better, heat-resistant foamed insulation with foil surface. The reflective layer should be facing the inside of the steam room. In this case, we will reduce to almost zero heat loss due to infrared radiation. The strips of material are mounted horizontally, from bottom to top, with an overlap of at least 5 centimeters. Then the seams are carefully glued with aluminum tape.
- On top of the vapor barrier is a counter grille - rails 1.5 - 2 centimeters thick. They will provide a ventilation gap.
- On the counter-lattice, the walls are sewn up with clapboard. At the same time, slots about 20 millimeters wide remain at the bottom and top of each wall, ensuring air circulation behind the casing.
Do not forget about fire safety. Despite the flame retardant impregnation, the furnace must be at least half a meter from the wooden wall or screened off with a fireproof material. The same applies to other sources of open fire: for example, projects of baths from glued laminated timber with a barbecue include elements of brickwork.
Under the first crown of laminated veneer lumber is laid the bottom trim - a timber made of rotting wood with reliable antiseptic impregnation. The trimming beam is separated from the foundation by waterproofing - two layers of roofing material.
As you can see, the material chosen by us has a lot of advantages and is able to save the builder from many of the difficulties associated with drying and shrinkage of solid wood. More information contains a video in this article, see!
Successes in construction!