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1950-51 Theatre Catalog, 9th Edition, Page 137 (117)

1950-51 Theatre Catalog, 9th Edition
1950-51 Theatre Catalog
1950-51 Theatre Catalog, 9th Edition, Page 137
Page 137

1950-51 Theatre Catalog, 9th Edition, Page 137

How to Keep Walls and Floors Dry

Special Waterproofing Compounds for Masonry and Cement Prevent Entry of Moisture

Because all concrete and other masonry surfaces are porous, either because of the natural evaporation of the water during the drying process or their inherent structural characteristics, fine pores and openings exist which may escape notice by the naked eye. When ground conditions prevent normal absorption of water, or when hydrostatic pressure builds up behind walls, such channels though microscopic invite Water seepage.

Scope of Waterproonng

The theatre operator should realize that waterproofing is a process which depends for its success upon a clear understanding of the underlying problems. For example, above ground and below ground conditions may pose vastly different problems. And well-drained soil and a temperate climate will present a simpler situation than poorly drained, heavy soil where hydrostatic pressures exist or where excessive rainfall or high humidities bedevil the land.

Quality materials correctly applied by experienced contractors in accordance with approved specifications written for the conditions encountered will provide satisfactory protection. But there are some things that waterproofing compounds will not do. They will not overcome defects in the structure itself, nor will they always compensate for poor design. However, within their proper scope, they will provide a continuous barrier against moisture over extended periods of time.

Various Types Available

Typical waterproofers include: inorganic compounds, metal-base compounds, asplhaltebase compounds, plasticbase protective coatings, cement water paints and, in a slightly diHerent application, plastic fioor tile. Although their chemical compositions vary, these protective waterproofing compounds all perform the same function of sealing up the pores in masonry and cement.

Inorganic Compounds

Inorganic waterproofing compounds in general are composed of inorganic powders, finely ground and properly balanced for optimum sealing. Mixed with water and brushed or sprayed on properly prepared porous masonry surfaces, they can be used on inside and outside surfaces, below or above grade. Their applications include: unglazed tile, concrete masonry, rough masonry, retaining walls, stucco surfaces, copings, cinder block walls, brick piers, brick walls, field and quarry stone, sand-grit blocks, sandstone, Indiana limestone, and other Itonelike materials.

Available in a variety of colors# gray, white, red, blue, green, buff and


BRIEF: Moisture in all its maliciousness . . . seeping through the walls and floors of a theatre . . . is an arch Nemesis of the motion picture house . . . It viciously mildews furniture . . . savagely rusts metal machinery and equipment . . . creates an environment which readily appeals to insects . . . There is nothing better calculated than such moisture . . . if left uncontrolled . . . to add a few more gray hairs to an ownefs head . . . This deadly enemy of the theatre can be kept in check, however . . . by use of several sound waterproofing compounds now available . . . These moisture stoppers . . . properly applied . . . will stop the foe right in his tracks . . . provided the basic structure has no serious defects . . . and is well designed.


cream a, the inorganic waterproofing compounds repel water by penetrating and sealing the pores of the concrete or masonry surfaces to which they are applied. In fact, it is the filling of the

pores and not essentially the surface coating which stops the penetration of water.

Proper surface preparation is important. All surfaces must be thoroughly cleaned before application of the waterproofer. All covering such as whitewash, fish oil, linseed oil paint, tar products, paraffine, casein paint, etc., must be removed to establish the needed porosity in the material to be treated. Surfaces should be free from sharp rock projections, nails,'wire, or anything else that prevents the formation of a continuous film. Holes, joints and cracks should be pointed up, door and window frames caulked and surfaces cleaned of dust, dirt, scale and loose particles.

After proper application by brush or spray on prepared and dampened surfaces, the inorganic waterproofing compound becomes completely hard and an integral part of the concrete or masonry to which it is applied. If the concrete is of sufficient thickness and strength, the waterproofer can be used successfully on surfaces under hydrostatic pressure.

Aid AIR GUN provides. a very acceptable method at application on large surfaces. In this closeup Mica Insul-Mastic is Ibeing sprayed on a masonry wall. This particular product is supplied in white or light shades and is highly adaptable for theatres. (Pboto caurteiy of land-Mani: Corporation of Amerim)

1950-51 Theatre Catalog, 9th Edition, Page 137