Jax-Lite: Jackson’s Native Concrete Block

Jax-Lite--4The recent Mad Mod Eastover tour and the review published here last week introduced me to the Lovelace House and its construction material, a lightweight concrete block known as “Jax-Lite.” I knew I had seen that name somewhere, and when I got back to my stash of old newspapers, I found it–a double-page spread about the new Jax-Lite plant opening in 1954. I’m told by an engineer of my acquaintance that Jax-Lite used Yazoo clay as its lightweight material, and is thus one of the few productive uses of this devilish soil we’ve been given.

The Jackson Ready Mix plant is still there, just north of the Woodrow Wilson bridge over the railroad tracks, near the old Farmer’s Market.

Note: I started to edit this very long article to make it shorter, but then I decided, hey, it’s the internet, y’all can scroll through and look at the pictures if you want, or the serious scholars can read the whole thing. You could even read some during your morning break and the rest during your afternoon break, or vice versa. You are the masters of your fate! Enjoy!



Jackson’s Newest Industry Manufactures new, lightweight building blocks with long-lasting benefits

With the beginning of operations of Jackson’s newest industry, Jackson Ready-Mix Concrete’s new quarter-million dollar manufacturing plant for the production of quality JAX-LITE Concrete Masonry Units, interest is being focused on a building product that is being acclaimed as “the most economical building material on the American market today.”

It is an entirely different product today as compared to the old type, back-yard-made concrete blocks which created a stigma as being the “ugly ducklin” of the building materials.

This new light-weight concrete building unit of today, manufactured to exacting specifications by modern equipment and scientific methods for strength, durability and fire-safety is gaining momentum in its nation-wide acceptance for several good reasons–and all good reasons why any owner would want to investigate the advantages and economical aspects of concrete masonry in whatever type of construction that may be planned. Improved materials, techniques and industrial know-how, resulting from some fifty-odd years of improving, now affords in a single-unit product almost all of the desired characteristics which are generally sought in a combining of various other materials in order to accomplish comparable values in sound, livable, and economical construction.

Whether it be in residences, churches, schools, auditoriums, multi-story skyscrapers, hospitals, theatres, stores, factory buildings, or farm structures, there is incorporated within versatile sizes, easy-to-lay building units almost every architectural design value desired in a structure, names: Beauty, Strength and Durability. In review of these outlines values there develops many interesting and revealing merits which add greatly to the overall economy of concrete masonry construction.

“BEAUTY,” As defined by Webster, “is that quality or aggregate of qualities in a thing which gives pleasure to the senses or pleasurably exalts the mind or spirit.”

In respect to beauty, the matter of appearance creates the first and most enduring impression. Concrete masonry units are by a wide margin the most versatile material available today. It is readily and completely adaptable to any style of architecture, whether it be French Provencial, Early American, Georgia or Streamlined Modern. It may be used for the simplest cottage or for the most elaborate mansion and yet, with even the most modest skill in handling, the material lends additional charm of the design itself.

Jax-Lite--2The range and variety of wall finishes that can be achieved is virtually unlimited. Various surface textures and colors can be obtained, but the greatest variety unquestionably results from the free play of creative imagination in the endless use of the product. It is for this reason that thousands of architects have enthusiastically adopted the material for their own, using it in ways, and to achieve effects, that were undreamed of a generation ago. The modern concrete masonry unit has at last provided a medium of construction which imposes no limitations of any sort upon the architect, and yet the range of its possibilities has been little more than scratched. Travelers visiting various sections of the country readily notice the very attractive applications that are being made in obtaining most attractive structures through this trend of design with concrete masonry.

STRENGTH and durability are basic characteristics of concrete in general. Walls built of these modern, quality-made concrete masonry units have a compressive strength of 700 to 1000 pounds per square inch, which develop exceptionally high strengths. Tests carried out at the University of Illinois indicate that concrete masonry walls are about twice as strong as clay brick walls built with units of approximately the same strength; and in frame construction it is virtually impossible to obtain strengths that are in any way comparable. The great strength of concrete masonry structures is perhaps best shown by their remarkable resistance to wind storms and other destructive forces. The Florida hurricane of 1926, for example, is believed to have been one of the most severe storms ever experienced in this country. Wind velocities soared as high as 125 miles per hour, and in some areas rainfall amounted to as much as 15 inches during the 16 hours that the storm raged. The City of Coral Gables, then the only community in the country restricted by law to concrete construction, was in the direct path of the hurricane. Some 2500 residences, apartments and other buildings, all constructed of concrete masonry units, survived the great storm without a single instance of total destruction, and only slight damage. Total damage to the city was not over $1,500,000, while less fortunate communities in the same area suffered staggering losses when flimsy structures by the thousands collapsed in the path of the storm. It is scarcely to be wondered that today concrete masonry construction predominates throughout the state.

Jax-Lite--3Homes and other structures built of concrete masonry show up equally well in areas which are subject to earthquakes, and the product has won equal preference in such areas. The inherent strength of concrete masonry units which enables walls of this material to withstand such extreme tests is desirable in any structure, regardless of its location and the service it is to perform. In the long run flimsy construction, by reason of its shorter useful life and infinitely higher maintenance cost, is far more costly.

DURABILITY: The term durability is used here in its general rather than in its technical sense. It covers collectively many of the most important characteristics of a concrete masonry structure–its immunity to wear, rot, and decay which afflict other types of construction; its ability to render good service for long periods of time without costly repairs; and its general strength and rigidity, resulting in freedom from warping and sagging and cracking which undermine the enjoyment and ultimately the whole value of ownership of the structure.

Just as concrete masonry building affords the best protection against destructive hurricanes and earthquakes, so do they provide the ultimate protection against all the destructive forces of nature. Even in the most benign climates the structures built by men are under constant assault–from driving rains, from freezing and thawing, from the intense glare of sunlight, and from the incredibly destructive attack of termites. No widely available building material resists these forces as well, or at such little cost, as concrete.

The subterranean termite deserves special mention in any discussion of durability. It has an insatiable appetite for cellulose, which is the chief constituent of wood, and it has acquired in recent years a marked taste for man-made lumber in preference to its original diet of dead timber. The cost of termite damage runs into millions of dollars every year and has led to the development of a new industry.

Since termites bore inside of timbers, leaving little or no surface trace of their activities, the first indication of their presence is usually the collapse of some portion of the infested structure. Termites have been reported in every one of the 48 states, and their depredations are equally prevalent in farm and urban areas.

Studies in certain areas have disclosed that in severe cases up to 90 percent of all residences may be either infested by termites, or seriously threatened by their presence in adjacent wooden structures. The repair of termite-damaged structural members and the measures necessary to exterminate the pests and bar their re-entry add up to tremendous expense for homeowners. In this battles, prevention is clearly the only economical defense. Complete and permanent protection against termites is assured when homes are built of concrete masonry in accordance with modern building codes, for the material affords them no nourishment and it presents an unbreachable barrier to keep them out. When floors and other structures members, as well as foundations, side walls, and partitions are constructed of concrete masonry, all important elements that go to make a home are completely and ever-lastingly termite-proof.

Jax-Lite--1FIRE RESISTANCE is another factor of no mean significance in consideration of concrete masonry construction. Statistics as to the loss of life and property due to fire each year in this country is alarming. The property loss runs into millions of dollars, and the loss of life, of course, is beyond monetary measurement.

Homes and structures of concrete masonry afford their owners the ultimate protection against destructive fires, for concrete is itself absolutely fireproof. When foundations and side walls, floors, and roofs are built of firesafe concrete masonry, the resulting structure is as fireproof as ingenuity can make it.

Fire-resistance ratings on concrete masonry are established by an independent, non-profit organization known as UNDERWRITERS’ LABORATORIES, INC., who, by actual laboratory fire tests made on various aggregates and materials used in the manufacture of concrete masonry units, determine the hours of fire resistance such products are eligible and entitled to be given. Their approval of the fire resistance of a product is confirmed with the issuance of an Underwriters’ Laboratories, Inc. certificate, indicating to insurance rating bureaus that the structure in which such units are uses are entitled to the benefits rate-wise for having been constructed of units identified by such quality of product.

For these reasons stated, a home built of concrete masonry is itself the best assurance against fire loss that money can buy. The mere knowledge that loved ons and personal possessions are secure from the ravages of fire, regardless of whether that security is ever subjected to severe test, is just one of the joys of living in a concrete masonry home. And, oddly enough, that security is not only obtainable at no increase in costs over other types of construction, but it stands to yield a dividend savings in the form of lower fire insurance rates.

INSULATION VALUES at no extra cost is made possible to a marked degree with walls constructed of concrete masonry. This is due to the cellular structure of the aggregate itself, which contains innumerable air cells. These have the same effect in slowing down heat transmission as has the dead air space between storm sash and regular windows.

In extremely hot climes, where home air conditioning is coming to be regarded as a necessity rather than a luxury, the insulating properties of lightweight concrete masonry show equal benefits in respect to both economy and comfort. In regions where day-time temperatures soar to the 100-mark or over, the natural insulating value of light-weight units, with or without additional assistance from other materials, forms a barrier against the heat, making it possible for cooler homes even where air conditioning units may be beyond the budget. Likewise, in cold weather, homes constructed of these units are less expensive to heat in comparison to the same comforts of other types of construction.

Jackson Daily News, Sunday, June 13, 1954, p.5

Can’t get enough concrete? You’re in luck!

Categories: Architectural Research, Jackson


2 replies

  1. Jackson Ready-Mix’s clay mine off Cynthia Road is where several prehistoric whale fossils were excavated. The clay was milled into small aggregate sized pieces and expanded in a rotary kiln thus creating the lightweight aggregate for the “lite-weight” concrete products.

    Liked by 2 people

    • Beauregard, you’ve answered the nagging question I had about the use of clay as aggregate in this application. Do you know the grading size of the aggregate after it was fired? Does the use of clay effect the strength and plasticity of the block?


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