The document discusses different types of flooring materials and construction methods. It describes the purposes of floors and factors to consider when selecting materials, such as cost, appearance, durability, moisture resistance, sound insulation and fire resistance. Various flooring materials are then outlined, including brick, flagstone, concrete, terrazzo, mosaic, tile and marble flooring. Construction techniques are provided for each type of flooring.
2. INTRODUCTION
THE PURPOSE OF A FLOOR IS TO PROVIDE A LEVEL SURFACE CAPABLE OF
SUPPORTING THE OCCUPANTS OF A BUILDING, FURNITURE,
EQUIPMENT AND SOMETIMES INTERNAL PARTITIONS. TO PERFORM
THIS FUNCTION, AND IN ADDITION, OTHERS WHICH MAY VARY
ACCORDING TO THE SITUATION OF THE FLOOR IN THE BUILDING AND
THE NATURE OF THE BUILDING ITSELF, A FLOOR MUST SATISFY THE
FOLLOWING REQUIREMENTS :
(I)ADEQUATE STRENGTH AND STABILITY
(II) ADEQUATE FIRE RESISTANCE
(III) SOUND INSULATION
(IV) DAMP RESISTANCE AND
(V) THERMAL INSULATION.
THE FLOORS RESTING DIRECTLY ON THE GROUND SURFACE ARE KNOWN
AS GROUND FLOORS, WHILE THE OTHER FLOORS OF EACH STOREY
SITUATED ABOVE THE GROUND LEVEL ARE KNOWN AS UPPER FLOOR.
3. MATERIALS USED
MATERIALS USED FOR CONSTRUCTION OF GROUND FLOOR BASE ARE :
(I)CEMENT CONCRETE
(II) LIME CONCRETE
(III) STONES
(IV) BRICKS
(V) WOODEN BLOCKS (FOR WOODEN FLOORING ONLY)
THE MATERIALS USED FOR FLOOR FINISH OR FLOOR COVERING ARE:
1. MUD AND MURAM 9. GRANOLITHIC FINISH
2. BRICKS 10. WOOD OR TIMBER
3. FLAG STONES 11. ASPHALT
4. CONCRETE 12. RUBBER
5. TERRAZZO 13. LINOLEUM FLOORING
6. MOSAIC 14. CORK
7. TILES 15. GLASS
8. MARBLE 16. PLASTIC OR P.V.C.
4. SELECTION OF MATERIAL
FOLLOWING ARE THE FACTORS THAT AFFECT THE CHOICE OF A
FLOORING MATERIALS:
(1) INITIAL COST: THE COST OF THE MATERIAL SHOULD BE IN
CONFORMITY WITH THE TYPE OF BUILDING AND ITS LIKELY USE.
(2) APPEARANCE: COVERING SHOULD GIVE PLEASING APPEARANCE, i.e.
IT SHOULD PRODUCE A DESIRED COLOR EFFECT AND
ARCHITECTURAL BEAUTY. FLOORINGS OF TERRAZZO, MOSAIC, TILES
AND MARBLE GIVE GOOD APPEARANCE.
(3) CLEANLINESS: THE FLOORING SHOULD BE CAPABLE OF BEING
CLEANED EASILY, AND IT SHOULD BE NON-ABSORBENT. IT SHOULD
HAVE EFFECTIVE RESISTANCE AGAINST ABSORPTION OF OIL, GREASE
ETC.
(4) DURABILITY: THE FLOORING SHOULD HAVE SUFFICIENT RESISTANCE
TO WEAR, TEMPERATURE CHANGES, DISINTEGRATION WITH TIME
AND DECAY, SO THAT LONG LIFE IS OBTAINED. FROM THIS POINT OF
VIEW, FLOORING OF MARBLE, TERRAZZO, TILES, CONCRETE, MOSAIC
ETC. ARE CONSIDERED TO BE OF BEST TYPE.
5. (5) DAMP RESISTANCE: FLOORING SHOULD OFFER SUFFICIENT
RESISTANCE AGAINST DAMPNESS, SO THAT HEALTHY
ENVIRONMENT IS OBTAINED IN THE BUILDING. FLOORING OF
CONCRETE, TERRAZZO, MOSAIC ETC. ARE PREFERRED FOR THIS
PURPOSE, WHILE FLOORING OF CORK, WOOD, RUBBER, LINOLEUM,
BRICK ETC. ARE NOT SUITABLE FOR DAMP CONDITIONS.
(6) SOUND INSULATION: FLOORING SHOULD INSULATE THE NOISE.
ALSO IT SHOULD NOT BE SUCH THAT NOISE IS PRODUCED WHEN
USERS WALK ON IT. CORK FLOORING, RUBBER FLOORING AND
TIMBER FLOORING ARE GOOD FROM THIS POINT OF VIEW.
(7) THERMAL INSULATION: THE FLOORING SHOULD OFFER
REASONABLY GOOD THERMAL INSULATION SO THAT COMFORT IS
IMPARTED TO THE RESIDENTS OF THE BUILDING. FLOOR COVERING
OF WOOD, RUBBER, CORK. P.V.C. TILES ARE BETTER FOR THIS
PURPOSE.
6. (8) FIRE RESISTANCE: THIS IS MORE IMPORTANT FOR UPPER FLOORS.
FLOORING MATERIAL SHOULD OFFER SUFFICIENT FIRE RESISTANCE SO
THAT FIRE BARRIERS ARE OBTAINED BETWEEN DIFFERENT LEVELS OF A
BUILDING. CONCRETE, TILES, TERRAZZO, MOSAIC, MARBLE HAVE GOOD
FIRE RESISTANCE. CORK, ASPHALT, RUBBER AND P.V.C. COVERINGS, IF
USED, SHOULD BE LAID ON FIRE RESISTANCE BASE ONLY.
(9) SMOOTHNESS: THE FLOORING MATERIAL SHOULD BE SMOOTH, AND
SHOULD HAVE EVEN SURFACE. HOWEVER, IT SHOULD NOT BE SLIPPERY.
(10) HARDNESS: IT SHOULD BE SUFFICIENTLY HARD SO AS TO HAVE
RESISTANCE TO INDENTATION MARKS, IMPRINTS ETC. LIKELY TO BE
CAUSED BY SHIFTING OF FURNITURE, EQUIPMENT ETC.
(11) MAINTENANCE: THE FLOORING MATERIAL SHOULD REQUIRE LEAST
MAINTENANCE. HOWEVER, WHENEVER REPAIRS ARE REQUIRED, IT
SHOULD BE SUCH THAT REPAIRS CAN BE DONE EASILY, WITH LEAST
POSSIBLE EXPENDITURE.
7. BRICK FLOORING
SUCH FLOORING IS USED IN CHEAP CONSTRUCTION,
SPECIALLY WHEN GOOD BRICKS ARE AVAILABLE.
THIS FLOORING IS SPECIALLY SUITED TO
WAREHOUSES, STORES, GODOWNS ETC. WELL-
BURNT BRICKS OF GOOD COLOUR AND UNIFORM
SHAPES ARE USED.
THE METHOD OF PREPARING THE BASE COURSE
FOR BRICK FLOORING VARIES FROM PLACE TO
PLACE IN ONE METHOD, THE SUBGRADE IS COMPACTED
PROPERLY, TO THE DESIRED LEVEL, AND A 7.5 CM
THICK LAYER OF SAND IS SPREAD. OVER THIS, A
COURSE OF BRICKS LAID FLAT IN MORTAR IS BUILT.
THIS FORMS THE BASE COURSE, OVER WHICH THE
BRICK FLOORING IS LAID IN 12 MM THICK BED OF
CEMENT OR LIME MORTAR IN THE DESIRED
PATTERN.
8. IN THE SECOND METHOD, 10 TO 15 CM THICK LAYER OF LEAN
CEMENT CONCRETE (1 :8: 16) OR LIME CONCRETE IS LAID OVER THE
PREPARED SUBGRADE. THIS FORMS THE BASE COURSE, OVER
WHICH BRICKS ARE LAID ON EDGE (OR FLAT) ON 12 MM THICK
MORTAR BED IN SUCH A WAY THAT ALL THE JOINTS ARE FULL WITH
MORTAR. IN BOTH THE CASES, THE JOINTS ARE RENDERED FLUSH
AND FINISHED. THE WORK IS THEN PROPERLY CURED.
FLAG STONE FLOORING
FLAG STONE IS ANY LAMINATED SAND STONE AVAILABLE IN 2 CM
TO4 CM THICKNESS, IN THE FORM OF STONE SLABS OF SQUARE (30
CM X 30CM. 45 CM X 45 CM OR 60 CM X 60 CM) OR RECTANGULAR
SIZE (45 X 60CM). THIS TYPE OF WORK IS ALSO CALLED PAVING. THE
STONE SLABS ARE LAID ON CONCRETE BASE. THE SUB-SOIL IS
PROPERLY COMPACTED, OVER WHICH10 TO 15 CM THICK LIME
CONCRETE OR LEAN CEMENT CONCRETE IS LAID. THIS FORMS THE
BASE COURSE OF THE FLOOR.
9. THE FLAG STONES (STONE SLABS) ARE THEN
LAID OVER 20 TO 25 MM THICK LAYER OF BED
MORTAR. IN LAYING THE SLABS, WORK IS
STAINED FROM TWO DIAGONALLY OPPOSITE
CORNERS AND BROUGHT UP FROM BOTH
SIDES. A STRING IS STRETCHED BETWEEN
TWO CORNER SLABS LAID FIRST TO CORRECT
LEVEL. OTHER SLABS ARE THEN SO LAID THAT
THEIR TOPS TOUCH THE STRING. IF ANY
PARTICULAR SLAB FALLS LOWER THAN THE
STRING LEVEL, IT IS RE-LAID BY PULLING
FRESH LAYER OF STIFF MORTAR. WHEN THE
STONE SLABS ARE PROPERLY SET, MORTAR IN
THE JOINTS IS RAKED OUT TO A DEPTH OF
ABOUT 15 TO 20 MM AND THEN FLUSH
POINTED WITH 1:3 CEMENT MORTAR.
PROPER SLOPE IS GIVEN TO THE SURFACE
FOR DRAINAGE. THE WORK IS PROPERLY
CURED.
10. CEMENT CONCRETE FLOORING
THIS IS COMMONLY USED FOR
RESIDENTIAL, COMMERCIAL AND EVEN
INDUSTRIAL BUILDING. SINCE IT IS
MODERATELY CHEAP, QUITE DURABLE
AND EASY TO CONSTRUCT. THE FLOOR
CONSISTS OF TWO COMPONENTS: (1)
BASE CONCRETE AND (II) TOPPING OR
WEARING SURFACE.
THE TWO COMPONENTS OF THE FLOOR CAN BE CONSTRUCTED
EITHER MONOLITHICALLY (I.E. TOPPING LAID IMMEDIATELY AFTER
THE BASE COURSE IS LAID) OR NON-MONOLITHICALLY. WHEN THE
FLOOR IS LAID MONOLITHICALLY, GOOD BOND BETWEEN THE TWO
COMPONENTS IS OBTAINED RESULTING IN SMALLER THICKNESS.
11. WHEN THE FLOOR IS LAID MONOLITHICALLY, GOOD BOND
BETWEEN THE TWO COMPONENTS IS OBTAINED RESULTING IN
SMALLER OVER ALL THICKNESS. HOWEVER.SUCH A CONSTRUCTION
HAS DISADVANTAGES. HENCE IN MOST OF THE CASES, NON
MONOLITHIC CONSTRUCTION IS PREFERRED.
GRANOLITHIC FINISH: IN INDUSTRIAL BUILDING, HARD WEARING
SURFACE IS SOMETIMES REQUIRED. THIS CAN BE ACHIEVED BY
APPLYING GRANOLITHIC FINISH OVER THE CONCRETE TOPPING
DESCRIBED ABOVE. GRANOLITHIC FINISH CONSISTS OF RICH
CONCRETE MADE WITH VERY HARD AND TOUGH QUALITY COARSE
AGGREGATE (SUCH AS GRANITE, BASALT, QUARTZITE ETC.)
12. TERRAZZO FLOORING
TERRAZZO FLOORING IS ANOTHER TYPE OF
FLOOR FINISH THAT IS LAID IN THIN LAYER
OVER CONCRETE TOPPING. IT IS VERY
DECORATIVE AND HAS GOOD WEARING
PROPERTIES. DUE TO THIS, IT IS WIDELY USED
IN RESIDENTIAL BUILDINGS, HOSPITALS,
OFFICES, SCHOOLS AND OTHER PUBLIC
BUILDINGS. TERRAZZO IS A SPECIALLY
PREPARED CONCRETE SURFACE CONTAINING
CEMENT (WHITE OR GREY) AND MARBLE CHIPS
(OR DIFFERENT COLORS), IN PROPORTION TO
1:1.25 TO 1:2.
WHEN THE SURFACE HAS SET, THE CHIPS ARE EXPOSED BY GRINDING
OPERATION. MARBLE CHIPS MAY VARY FROM 3 MM TO 6 MM SIZE. COLOR
CAN BE MIXED TO WHITE CEMENT TO SET DESIRED TINT. THE FLOORING IS,
HOWEVER, MORE EXPENSIVE.
13. MOSAIC FLOOR
MOSAIC FLOORING IS MADE OF SMALL
PIECES OF BROKEN TILES OF CHINA
GLAZED OR OF CEMENT, OR OF MARBLE,
ARRANGED IN DIFFERENT PATTERN. THESE
PIECES ARE CUT TO DESIRED SHAPES AND
SIZES. A CONCRETE BASE IS PREPARED AS
IN THE USE OF CONCRETE FLOORING, AND
OVER IT 5 TO8 CM THICK LIME-STONE
MORTAR IS SPREAD AND LEVELED, OVER
AN AREA WHICH CAN BE COMPLETED
CONVENIENTLY WITHIN WORKING PERIOD
SO THAT THE MORTAR MAY NOT GET
DRIED BEFORE THE FLOOR IS FINISHED ON
THIS.
14. A 3 MM THICK CEMENTING MATERIAL, IN THE FORM OF PASTE OF
TWO PARTS OF SLAKED LIME, ONE PART OF POWDERED MARBLE AND
ONE PART OF POZZOLANA MATERIAL, IS SPREAD AND IS LEFT TO DRY
FOR ABOUT 4 HOURS. THERE AFTER, SMALL PIECES OF BROKEN TILES
OR MARBLE PIECES OF DIFFERENT COLORS ARE ARRANGED IN
DEFINITE PATTERNS AND HAMMERED INTO THE CEMENTING LAYER.
THE SURFACE IS GENTLY ROLLED BY A STONE ROLLER OF 30 CM DIA.
AND 40 TO 60 CM LONG, SPRINKLING WATER OVER THE SURFACE. SO
THAT CEMENTING MATERIAL COMES UP THROUGH THE JOINTS, AND
AN EVEN SURFACE IS OBTAINED. THE SURFACE IS ALLOWED TO DRY
FOR 1 DAY, AND IS. THEREAFTER, RUBBED WITH A PUMICE STONE
FILLED WITH A LONG WOODEN HANDLE, TO GET SMOOTH AND
POLISH SURFACE, THE FLOOR IS ALLOWED TO DRY FOR TWO WEEKS
BEFORE USE.
15. TILED FLOORING
TILED FLOORING IS CONSTRUCTED FROM
SQUARE, HEXAGONAL OR OTHER SHAPES,
MADE OF CLAY ( POTTERY), CEMENT CONCRETE
OR TERRAZZO. THESE ARE AVAILABLE IN
DIFFERENT SIZES AND THICKNESSES. THESE ARE
COMMONLY USED IN RESIDENTIAL HOUSES,
OFFICES. SCHOOLS, HOSPITALS AND OTHER
PUBLIC BUILDINGS, SPECIALLY WHERE THE
FLOOR IS TO BE LAID QUICKLY. OVER THE
CONCRETE BASE, A 25 TO 30 MM THICK LAYER
OF LIME MORTAR 1:3 (1 LIME AND 3 SAND) IS
SPREAD TO SERVE AS BEDDING. THIS BEDDING
MORTAR IS ALLOWED TO HARDEN FOR 12 TO24
HOURS. BEFORE LAYING THE TILES, NEAT
CEMENT SLURRY IS SPREAD OVER THE
BEDDING MORTAR AND THE TILES ARE LAID
FLAT OVER IT.
16. GENTLY PRESSING THEM INTO THE BEDDING MORTAR WITH THE
HELP OF WOODEN MALLET, TILL LEVELLED SURFACE IS OBTAINED.
BEFORE LAYING THE TILES. THIN PASTE OF CEMENT IS APPLIED ON
THEIR SIDES, SO THAT THE TILES HAVE A THIN COAT OF CEMENT
MORTAR OVER THE ENTIRE PERIMETER SURFACE. NEXT DAY, THE
JOINTS BETWEEN ADJACENT TILES ARE CLEANED OF LOOSE
MORTAR ETC TO A DEPTH OF 5 MM, USING WIRE BRUSH, AND
THEN GROUTED WITH CEMENT SLURRY OF THE SAME COLOR
SHADE AS THAT OF THE TILES. THE SLURRY IS ALSO APPLIED OVER
THE FLOORING IN THIN COAT. THE FLOORING IS THEN CURED FOR 7
DAYS, AND THEN GRINDING AND POLISHING IS DONE IN THE SAME
MANNER AS THAT FOR TERRAZO FLOORING.
17. MARBLE FLOORING
IT IS A SUPERIOR TYPE OF FLOORING, USED IN
BATH-ROOMS AND KITCHENS OF RESIDENTIAL
BUILDINGS, AND IN HOSPITALS.
SANITORIUMS, TEMPLES ETC. WHERE EXTRA
CLEANLINESS IS AN ESSENTIAL REQUIREMENT.
MARBLE SLABS MAY BE LAID IN DIFFERENT
SIZES, USUALLY IN RECTANGULAR OR SQUARE
SHAPES.. OVER THE BASE CONCRETE, 20 MM
THICK BEDDING MORTAR OF EITHER 1:4
CEMENT: SAND MIX OR 1 (LIME PUTTY) : I (
SURKHI) : 1COARSE SAND MIX IS SPREAD
UNDER THE AREA OF EACH INDIVIDUAL SLAB.
THE MARBLE SLAB IS THEN LAID OVER IT,
GENTLY PRESSED WITH WOODEN MALLET
AND LEVELLED.
18. THE MARBLE SLAB IS THEN AGAIN LIFTED UP, AND FRESH MORTAR
IS ADDED TO THE HOLLOWS OF THE BEDDING MORTAR. THE
MORTAR IS ALLOWED TO HARDEN SLIGHTLY, CEMENT SLURRY IS
SPREAD OVER IT THE EDGES OF ALREADY LAID SLABS ARE SMEARED
WITH CEMENT SLURRY PATE, AND THEN THE MARBLE SLAB IN
QUESTION IS PLACED IN POSITION. LT IS GENTLY PUSHED WITH
WOODEN MALLET SO THAT CEMENT PASTES OOZES OUT FROM THE
JOINT WHICH SHOULD BE AS THIN AS POSSIBLE (PAPER THICK). THE
PAVED AREA IS PROPERLY CURED FOR A WEEK.
19. TIMBER FLOORING
TIMBER FLOORING IS USED FOR CARPENTRY
HALLS, DANCING HALLS, AUDITORIUMS. ETC.
THEY ARE NOT COMMONLY USED IN
RESIDENTIAL BUILDINGS IN INDIA, BECAUSE
TIMBER FLOORING IS ALSO QUITE COSTLIER.
HOWEVER, IN HILLY AREAS, WHERE TIMBER
IS CHEAPLY AND READILY AVAILABLE, AND
WHERE TEMPERATURE DROP VERY LOW,
TIMBER FLOORING IS QUITE COMMON. ONE
THE MAJOR PROBLEMS IN TIMBER
FLOORING IS THE DAMP PREVENTION. THIS
CAN BE DONE BY INTRODUCING D.P.C. LAYER
BELOW THE FLOORING.
20. TIMBER FLOORS CAN EITHER BE OF SUSPENDED TYPE (I.E.
SUPPORTED ABOVE THE GROUND) OR ‘SOLID TYPE‘ (FULLY
SUPPORTED ON THE GROUND). THE HOLLOW SPACE BETWEEN THE
FLOORING AND OVER SITE CONCRETE IS KEPT DRY AND WELL-
VENTILATED BY PROVIDING AIR BRICKS IN THE OUTER WALLS. AND
VOIDS IN THE SLEEPER WALL. THE FLOORING CONSISTS OF
BOARDING SUPPORTED ON BRIDGING OR FLOOR JOISTS OF
TIMBER, WHICH ARE NAILED TO THE WALL PLATES AT THEIR ENDS.
SLEEPER WALLS ARE NOT SPACED MORE THAN 1.8 TO 2 M.
WHERE THE PROBLEMS OF DAMPNESS IS NOT ACUTE, TIMBER
FLOORS MAY BE SUPPORTED ON THE GROUND ALL ALONG. FOR
THIS TYPE OF CONSTRUCTION, BASE CONCRETE IS FIRST LAID IN 15
TO 20 CM THICKNESS. OVER IT, A LAYER OF MASTIC ASPHALT IS
APPLIED. WOODEN BLOCK FLOORING IS THEN LAID OVER IT.
21. WOODEN BLOCKS ARE SHORT BUT THICK AND ARE LAID IN
SUITABLE DESIGNS. IN ORDER TO FIX THE WOODEN FLOOR ON
CONCRETE SLABS, LONGITUDINAL NAILING STRIPS, WITH BEVELLED
SECTION, ARE EMBEDDED IN CONCRETE AT SUITABLE INTERVAL.
SOMETIMES, SPECIAL CONCRETE, CALLED NAILING CONCNETE MAY
BE USED AS AN ALTERNATIVE TO THE NAILING STRIPS. SPECIAL
FLOORING NAILS ARE USED FOR NAILING DOWN THE FLOORING.
22. ASPHALT FLOORING
1. ASPHALT MASTIC FLOORING: ASPHALT MASTIC IS A
MIXTURE OF SAND AND ASPHALT IN THE RATIO OF 2:1, MIXED
HOT AND THEN LAID IN CONTINUOUS SHEETS. IT CAN ALSO
BE APPLIED COLD, BY MIXING WITH MINERAL OIL AND
ASBESTOS. THE THICKNESS OF THE ASPHALT MASTIC MAY BE
2.5 CM FOR ORDINARY CONSTRUCTION. IT IS LAID ON
CEMENT CONCRETE BASE COURSE. THE MIX IS POURED ON
THE CONCRETE BASE. AND IS SPREAD BY MEANS OF TROWEL
TO GET LEVELLED SURFACE. ON THE TOP OF THE SURFACE, A
THIN LAYER OF SAND IS SPREAD, WHICH IS THEN RUBBED
WITH A TROWEL. THE JOINTS OF MASTIC ASPHALT LAID ON
SUCCESSIVE DAYS ARE PROPERLY LAPPED.
23. 2. ASPHALTIC TILES: THESE ARE PREPARED FROM ASPHALT,
ASBESTOS FIBRES, INERT MATERIALS AND MINERAL PIGMENTS, BY
PRESSING THE MIX IN DIFFERENT SIZES (20 CM SQUARE TO 45 CM
SQUARE), WITH THICKNESS VARYING FROM 3 TO 6 MM. THESE
TILES ARE EITHER DIRECTLY CEMENTED TO CONCRETE BASE OR ARE
FIXED TO WOODEN FLOORS BY USING AN INTERVENING LAYER OF
MASTIC ASPHALT OR ASPHALT SATURATED FELT. ASPHALTIC TILES
ARE CHEAP, RESILIENT, SOUND PROOF, NON-ABSORBANT AND
MOISTURE PROOF.
3. ASPHALTIC MOSAIC: THIS IS PREPARED SIMILAR TO MASTIC
ASPHALT, EXCEPT THAT MARBLE CHIPS ARE USED IN THE PLACE OF
SAND/GRIT. ASHPHALT MAY BE EITHER IN BLACK OR OTHER
SUITABLE COLOUR, AND IS LAID IN HOT CONDITION.
24. 4. ACID PROOF MASTIC FLOORING: ACID PROOF BLOCKS OF
ASPHALT ARE AVAILABLE, WHICH ARE MANUFACTURED FROM
MOULDING ACID PROOF ASPHALT AND INERT CRUSHED ROCK
AGGREGATE UNDER HIGH PRESSURE. THE ASPHALT BLOCKS ARE
FIRST LAID ON CONCRETE BASE THEN ACID PROOF ASPHALT IS
UNIFORMLY SPREAD OVER THE SURFACE OF THE BLOCKS. FINE
SAND IS SPREAD OVER THE LIQUID ASPHALT BEFORE IT HARDENS.
25. RUBBER FLOORING
IT CONSISTS OF SHEETS OR TILES OF
RUBBER, IN VARIETY OF PATTERN
SAND COLORS WITH THICKNESS
VARYING FROM 3 TO 10 MM. THE
SHEET OR TILE IS MANUFACTURED
BY MIXING PURE RUBBER WITH
TILLERS SUCH AS COTTON FIBRE,
GRANULATED CORK ORASBESTOS
FIBRE. THE SHEETS OR TILES ARE
FIXED TO CONCRETE BASE OR
WOOD BY MEANS OF APPROPRIATE
ADHESIVES. RUBBER FLOORINGS ARE RESILIENT AND NOISE PROOF.
HOWEVER, THEY ARE COSTLY. THEY ARE USED ONLY IN OFFICE OR
PUBLIC BUILDINGS.
26. GLASS FLOORING
THIS IS A SPECIAL PURPOSE FLOORING, USED
IN CIRCUMSTANCES WHERE IT IS DESIRED TO
TRANSMIT LIGHT FROM UPPER FLOOR TO
LOWER FLOOR, AND SPECIALLY TO ADMIT
LIGHT AT THE BASEMENT FROM THE UPPER
FLOOR. STRUCTURAL GLASS IS AVAILABLE IN
THE FORM OF TILES OR SLABS, IN
THICKNESSES VARYING FROM 12 TO 30 MM.
THESE ARE FIXED IN CLOSELY SPACED FRAMES
SO THAT GLASS AND THE FRAME CAN SUSTAIN
ANTICIPATED LOADS. GLASS FLOORING IS VERY
COSTLY, AND IS NOT COMMONLY USED.