When a water pipe breaks or natural disaster happens there are considerable damage to buildings. For floor coverings, e.g. as wood, carpet, stone, PVC Water damage is an extreme stress, since these coverings are typically designed for use in dry conditions.
LÄGLER® was effected by such damage due to a heavy storm last August.
Read on to see what happened to us...
In August 2015, there was a heavy storm in Frauenzimmern, in which some parts of the town were flooded and parts of the LÄGLER® - factory as well. At LÄGLER® the main damage happened in the classroom, where the theory part of the PST® takes place, which is covered with solid wood flooring.
Although the fire department reacted quickly to pump out the water, the whole classroom was flooded for some time with several centimeters of water and the wood floor was soaked with water.
Wood has many positive features and is an excellent material for floors. It is pleasant to walk on and provides an excellent indoor climate. But where there are benefits, there are drawbacks. A disadvantage is that wood is susceptible to high humidity levels. The tubular structure of the wood cells and the tendency to absorb moisture from the environment, the water can quickly and in larger quantities get into the core of the wood. It soaks the water in like a sponge and swells. Cupping is the result. Since each type of wood has a different cell structure and differing swelling behavior, the damage can be minor or extreme. Therefore, it is important to remove the water as quickly as possible from the wood.
After pumping out the water we determined with a moisture meter, how much water has been soaked into the wooden floor and the walls of the classroom. The first measurements shortly after removal of the water already showed the extent of the damage. On the outside wall to the courtyard particularly high moisture levels were measured. On the upper part of the outer wall 37% of moisture were measured...
The lower we measured (measuring points 1 ... 6), the higher the values. At measuring point 6 close to the floor, before drying, even 70% moisture were measured.
To achieve a successful restoration of the wood floor, the repair steps required need to be determined after the removal the water.
It is very important that the wood floor is still fully bonded to the substrate. If bigger parts of the floor are not aheared to the substrate, the entire floor has to be removed and replaced.
The affected classroom was, after the first evaluation, in a pretty bad shape. Single pieces were highly cupped and some extremely swollen. In some places, the floor was raised severely and measured several mm (Pic. 6).
When we checked the bonding we didn't find any loose boards.
Since the wood was not too swollen and still bonded well to the substrate, we decided to sand the floor. In order to avoid mistakes during the drying process, an expert in construction drying was consulted.
To initiate the drying process, the wood floor was sanded roughly on the advice of the expert before drying with a dehumidifier. By removing the finish layer with a 36 grit on the HUMMEL® the moisture could be removed faster from the wood and the cupping was almost completely eliminated (Pic. 7).
The second sanding cut with the HUMMEL® at a grit 60 followed. Both cuts were performed at an angle of 15° to the direction of the laying pattern / grain.
It is crucial that the drying process of the wood floor is done uniformly and not too fast. The expert in dehumidification provided us with a commercial dehumidifier that is designed for the volume of about 300 m3 / 10600 ft3 (Pic. 8).
A week after the rough cut we started drying using the dehumidifier. The unit was placed in the conference room and operated over a period of 2 weeks. During the drying process to check the progress, the moisture content was measured at different points in the room and on the wood floor.
While the humidity and the soil temperature remained relatively constant, the moisture content steadily declined for a total of about 5 weeks drying time, an acceptable value of 12.5% moisture content was reached. The result table in Pic. 9 shows the moisture content during the drying process.
To achieve a high quality surface, the parquet floor was sanded, after drying, with the TRIO and a 60, 80, 100 grit sequence according to the PST®.
Since the LÄGLER® classroom is used frequently and had to be operational again soon, it was advantageous to use UV finish.
In the consultation with the manufacturer of the UV finish we decided that the wood floor should be oiled before the UV cure. Therefore, we performed an optional cut with the TRIO at a 120 grit sand paper and 120 grit sanding screens to achieve a finer surface structure (Pic. 10).
The first step we applied a 2 component oil that was buffed in with a beige pad and the SINGLE (Pic. 11). After the recommended drying time of the oil the first finish layer was rolled on.
A few days before, during and after the work LÄGLER® staff checked the indoor climate (Pic. 12). The measured values were safe, so that the work could be continued and completed by the curing of the UV finish. A UV coating has the advantage that the surface can be operated faster. The UV finish, however, has to be cured with a special UV machine.
After the drying of the first finish layer a second finish layer was applied without intermediate sanding and also allowed to dry.
Then the final coat (Pic. 13) was cured by strong ultraviolet radiation with a specially adapted mobile UV light. This hardens the finish instantly and forms a resistant protective layer.
For lack of experience in dealing with UV finish an expert should be consulted in any case, otherwise this may lead to poor results. In addition, training is required for working with the mobile UV light, otherwise the safety of the operator (eyes) is threatened by the strong radiation.
Wood is sensitive to too much moisture. When it comes to water damage, it is important to remove the water as quickly as possible and then to dry the wood floor slowly with the help of an expert.
Is the bond between wood flooring and the sub floor still intact, in most cases the the wooden floor can be repaired.
When the moisture levels decrease to normal levels, the wood floor can be sanded as usual. In our case, to speed up the process UV finish was a great choice. The the first coat of oil before the UV finish ensures a smooth, matte, natural-looking surface (Pic. 14). The protective effect of the UV finish is stronger than conventional finishes. By the way a few weeks ago the same floor got hit again with water...
The exhibition "HOLZ-HANDWERK" in Nürnberg attracted along with with the "Fensterbau Frontale" around 110,000 visitors, including many from abroad. From March 16 to 19 1,296 exhibitors from 40 countries presented their products to the public and made the "HOLZ-HANDWERK 2016" to an impressive industry highlight, which also LÄGLER® could not miss.
The internationally significant exhibition "NWFA Wood Flooring Expo " with topics related to wood floors took place from 27 - April 30, 2016 and was held in Charlotte / North Carolina, USA.
LÄGLER® focus this year was the merge with long time partner Palo Duro Hardwoods Denver / USA and the introduction of the PST® to the North American market.