Wood Composite Flooring 



Editor's Note 



A brief article reprinted some months ago in Hardwood Record from tlie Daily Consular and Trade Reports, written 

 by Robert P. Skinner, United States consul general at Hamburg, involving tbe manufacture and use in Germany of a 

 flooring composed of sifted sawdust and chloride of magnesium, has attracted widespread attention among readers, 

 and we have had numerous requests for further information on the subject. For the following valuable detailed report 

 covering this material, wo are indebted to Consul General Skinner. 



From specimens of this material received at this office it would look as though there might be an important com- 

 mercial pursuit built in the United States founded on the German method, and xitilize to no inconsiderable extent a 

 vast amount of forest and sawmill offal, including sawdust, that now has little commercial value. 



Publication of the report from the Hamburg consulate genera], 

 dated June 20, 1911, entitled "Floorings of Sawdust and Mag- 

 nesium Chloride," has given rise to innumerable inquiries from 

 correspondents from various parts of the United States, all of 

 whom express a desire for further details. It was stated in the 

 original report that an extensive use was being made in Germany 

 of a flooring composition consisting of a solution of chloride of 

 magnesium to which pulverized magnesia is added together with 

 considerable proportions of sawdust, and which being compounded 

 with skill provided a relatively inexpensive and fairly fire-proof 

 flooring material, especially useful in large office buildings and 

 public halls. One inquirer now states that the art of laying these 

 floorings in Germany is far ahead of the practice in America and 

 he asks particularly for the method of coloring the material and 

 of governing its expansion and contraction. 



According to my information there should be neither expansion 

 nor contraction of the material from any cause whatever after a 

 flooring of magnesium chloride is once laid. The very ingredients 

 are such that there is no buckling nor cracking due to heat or 

 cold. In Hamburg the composition is mixed and spread where the 

 building operations are being carried on, the prepared dry meal 

 being delivered in bags from the factory and the lye water made 

 on the spot. It is impossible to state the precise rule for the 

 composition of the meal or for the lye solution, these being the 

 manufacturers' secrets and each manufacturer claiming particular 

 merits for his own formula. These formulae are not patented and 

 there is no doubt that they are all substantially alike. Several 

 manufacturers have expressed a willingness to sell their process, 

 either for the whole of the United States or for restricted terri- 

 tory. One Hamburg firm sold their formula for a small place in 

 southern Germany for $1,428. 



The mixture of meal and lye water is made in a mortar box 

 and when a thickness of not more than two inches is proposed, it 

 is spread and smoothed with a hand trowel; when a thickness of 

 four inches is requested, as is often the case, the material is tamped 

 and then smoothed. The amount of lye water used in mixing the 

 meal depends upon whether the flooring is to be simply spread or 

 tamped; if spread the ordinary practice seems to be to use from 

 four to six buckets of the lye water to one sack of meal, the sack 

 apparently containing from fifty to sixty pounds. 



These floorings were first utilized in large office buildings in 

 Hamburg, and probably elsewhere, as a basic flooring for linoleum 

 and also for the addition of artificial wood-marble flooring. These 

 wood-marble floorings are substitutes for wood and the panels are 

 polished like hardwood floors, that is to say, smoothed with steel 

 shavings and given a coating of wax. When linoleum is applied 

 >t is glued to the magnesium chloride foundation with a linoleum 

 cement whch is said to be composed of copal-resin and putty. It 

 may be remarked here that linoleum in Germany is never tacked 

 to wood or artificial stone flooring, as is usual in the United States, 

 but is invariably glued in place, an ordinary flour paste being used 

 when it is applied to wooden floors. Linoleum thus laid is washed 

 afterwards with soap-water and when dry is then given a coating 

 of wax exactly like a hardwood floor. This treatment is the ordi- 

 nary practice in the large office buildings in Germany, even in 

 hallways where thousands of people pass in the course of a week. 

 The magnesium chloride flooring was first considered a particu- 

 larly excellent foundation for linoleum and it is only in compara- 

 tively recent times that it has been found possible to color it ancl 

 to lay it so attractively that no linoleum covering is necessary. 



It is laid tight against the sidewalls, making the entire floor water- 

 proof. In bath rooms and around toilets it is brought to the edge 

 of the porcelain and the joints are rounded upwards so that no 

 crevices present themselves in which dust or dirt can collect, nor 

 should there be any .ioint through which water might percolate. 

 The favor in which linoleum is held in this country is such that 

 manufacturers of this new composition flooring have some diffi- 

 culty in inducing buyers to put down this material, in solid or 

 varied colors, in preference to a similar natural color foundation 

 with linoleum covering, although the cost and wearing qualities 

 of the former method are said to be much in its favor. Lino- 

 leum costs in Hamburg about eighty-six cents per square meter 

 and the cheapest class of magnesium chloride foundation pave- 

 ment costs forty-eight cents, making a total of $1.34 per square 

 meter, against a cost of $1.19 per square meter for a colored wood- 

 marble floor attractively finished. The new floorings may be 

 obtained now in almost any color, or in mottled colors. When 

 mottled colors are desired the different colored mixtures are pre- 

 pared separately and tamped in together as the floor is laid. 

 Special dyes are required for these operations and there are a 

 number of manufacturers who produce them, the addresses of 

 several being supplied below. In a general way from 7 to 10 

 kilos (15.4 to 22 pounds) of color are necessary to 220 pounds of 

 mortar. The proportions increase or decrease accordingly as a 

 light or strongly colored floor is desired. The colors themselves 

 are of different prices. For example one manufacturer quotes 

 red, blue, black and brown at $4.76 per 220 pounds; oxide green 

 $53.55 and blue from $19.04 to $21.42 per 220 pounds. Another 

 manufacturer quotes red dye, very much in demand, at an average 

 price of $3.81 per 220 pounds. The prices again vary with the 

 quantity ordered. The more delicate tints such as green and blue 

 are more sensitive to light, particularly if exposed for a long 

 time, than the quiet colors, such as black, red and brown. Bed, 

 especially, is a color greatly in favor and the many different 

 shades are said to be absolutely unchangeable. Most of the manu- 

 facturers of these dyes also supply dyes for cement tiles, stucco, 

 imitation marble, sand lime bricks and cement blocks. 



One Hamburg manufacturer claims for his own composition 

 that it is crack free under all circumstances, warm under foot, 

 elastic and sound proof; preferable to linoleum, as linoleum curls 

 at the edges after a time, breaks or wears away, also absorbing 

 water and permitting it to leak through. This same manufac- 

 turer submits a certificate of examination from the Eoyal Board 

 of Examiners of Material in the Technical High school in Berlin, 

 the date of which is November 19, 1906, reporting as follows on 

 the examination of samples of his material: 



1 — After the sample plates were soaked in water and had been exposed 

 to frost twenty-five times at 15 degrees below zero C, the samples remained 

 unharmed ; , 



2 — After the plates had been lying in water for eight days a very 

 small proportion of water (9%) had been absorbed; 



3 — After the plates had been attached to a vessel containing water, 

 after twenty-four hours NONE, atter forty-eight hours 2 cu. cm. = 5%, 

 after seventy-two hours 4 cu. cm. = 10% of moisture had been absorbed. 



This manufacturer also claims that in this country his compo- 

 sition is cheaper than pine flooring, tiling or stone; that it may 

 be used to cover old wornout wood and stone-plate floorings, stair- 

 cases and the like, without the necessity of removing the old 

 floors. Wherever a foundation is firm and dry it may be laid 

 without any complicated preparations. Finally it may be cleaned 

 with cold water and only very seldom should luke-warm soap- 

 water be applied. After complete cleansing and being thoroughly 



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