- Material selection
- Sphagnum moss
- Jute rope
- Modern materials
- Caulking technology
- Secondary caulk
Caulking the walls of a log house is a time-consuming process that, subject to its technology, will ensure the preservation of heat in the house in cold weather. A detailed analysis of the sequence of work, the correct choice of tool and material, presented in this article, will help you do the insulation of the seams with your own hands.
The main tools for caulking seams are the spatulas (caulkers) and mallet. The blades are made of wood or steel. Caulking wood should be softer than the log material, otherwise there will be marks on the walls. Over time, the working surface of the wooden caulk is shaggy, then it is replaced with a new one.
Metal caulkers are used for corner cuts where it is especially important to fill the interior of the bowl. With a mallet, gently tapping on the caulk, they compact the insulation roller and advance it into the seam.
To insulate and seal the seams in log walls, natural material (moss, jute, tow, etc.) and modern artificial polyurethane foam, polyethylene foam, mineral wool and other mezhventsovy heaters are used.
Moss has been preferred in the past for insulating log mating. Sphagnum and cuckoo flax (red flax) were laid in the seams of the frame. Sphagnum moss was fluffed up and laid across the logs in several layers (5-10 cm), hanging down to 5 cm from the seam. Flax cuckoos were placed along the crown and also in several layers (5-10 cm) with overlapping joints.
Before laying, the moss is soaked, and it dries already in the wall structure. By absorbing moisture, the moss gives it up quickly enough and does not rot. By its natural qualities, it is a very good antiseptic, therefore it also protects wood from biocorrosion. Its disadvantages include the complexity of a uniform device along the seam thickness.
Jute fiber is made from the jute plant, which belongs to the linden family. Jute caulking heaters are more durable, durable and moderately hygroscopic. Even with high humidity in the room, for example, in baths, jute absorbs no more than 20% moisture.
Tow is a tangled linen fiber. It is made from flax scuttling and crushing waste. There should be no foreign impurities in it, a small amount of fire is allowed (lignified part of the stem). Tow for caulking can only be used dry, soft and without putrefactive odor. The inter-crown seam of tow should be 0.8-1.2 cm.
Previously, hemp was also used for caulking log cabins. It was obtained by prolonged soaking of hemp stems in running water (up to 2-3 years). It is distinguished by the strength of the fibers, resistance to decay and exposure to sunlight. Today, hemp products are also presented in the range of building materials..
The use of artificial materials for caulking seams is becoming more widespread. These include mineral wool, polyethylene foam, and sealants. Their advantages are: bio- and moisture resistance, elasticity and vapor permeability, which is important for wood. Self-expanding sealing cords for an almost perfect seam seal.
The whole process of caulking log walls can be divided into two stages. During the assembly of the log house, the first stage is performed. The insulation is spread over the top of the mounted log. For the convenience of caulking, a felt tape is used, the raw material for which can be flax, jute, hemp.
The hanging ends of the seal, after the installation of the logs, are simply wrapped in their joints. The caulking of log seams is carried out in two ways: “stretching” and “in a set”. During the construction of a log house, the “stretching” method is most often used. For this, the free edges of the insulation are rolled up with a roller, which is pressed into the seam. The roller width should be 1-2 cm.
In the case of fibrous loose insulation (moss, tow), when folding the roller, it is important to select the adjacent hanging ends, constantly twisting them with the previous ones to obtain an even and durable seam.
The “set” is usually sealed with the second caulking, which is done after the building has shrunk (after 1-2 years). Walls made of logs give sediment due to the compression of the insulation in the seams and the shrinkage of the forest.
When the ends of the insulation are not enough to create a bead or the seams are too wide during the initial caulking, the “set” method is used. For this, a tourniquet is prepared in advance from the selected sealant; you can use a ready-made rope or rope of the required thickness. Loops are made into wide seams from the bundle, which are hammered into the space between the logs until the required compaction.
The work on the caulking of the log house always begins with the lower crown and is carried out along the entire perimeter of the seam. First, the outer side of the log mating is compacted, and then the inner side. It is possible to move on to the next crown only when the entire previous one has been drilled.
A tourniquet or roller is fixed in the seam with a caulk, which is tapped first on the upper part of the insulation, then on the lower and only then in the middle. If necessary, use a mallet hammer, hitting the end of the caulking handle with it.
During the sealing of the log joints, it is necessary to constantly check the horizontal position of the logs and the verticality of the walls. The seemingly simple process of compaction may well distort the position of individual parts of the structure of the house, move them from their original place or raise them.
Modern technologies for protecting the connection of logs in a log house provide for sealing the seam (warm seam). The advantages of this solution for joints in wooden houses are:
- resistance to sunlight and environmental influences;
- high thermal insulation properties;
- vapor permeability;
Sealing of seams is done as a re-caulking. The technology of the device “warm seam” basically consists of the following stages:
- Preparation of the surface of the seam to be insulated. To do this, clean the logs at the place of work from dust, dirt, grease stains. The sealant may not harden on walls covered with varnish, wax, or any oils. It is better to test the adhesion of the sealant to the treated log surface before starting work..
- Installation of a sealing cord, for example made of extruded polyethylene. It cannot be glued to the wall, it is simply inserted into the seam.
- Sealant application. Before starting to cover the cord and part of the logs with a sealant, the wooden surface is moistened. You can stick masking tape on both sides of the seam to ensure the same coverage width. The sealant is applied, depending on the packaging, either with a spatula or with an assembly gun. Layer thickness is allowed not less than 4 mm, but not more than 10 mm.
- Seam formation. The joint is smoothed and shaped with a suitable trowel within 15 minutes after applying the sealant. Then you can remove the masking tapes. Excess substance is cleaned with a damp cloth or sponge.
Patience and thoroughness of the caulking work will be fully justified by the durability of the structure and the warm walls of the house, so that you do not have to repair cracks later. The choice of an effective method of insulating log joints and a sufficient amount of material for this will significantly reduce the cost of heating in cold weather.