Materials For Construction Flashcards
- most prevalent raw material
- unique and valuable
- distinct advantage to feasibility
Wood
-Timber Sawn
- split in the form of beams, boards, joists, planks
Lumber
Coniferous or cone bearing, needle leafed
Softwood
Deciduous or broad leafed trees. From flowering plants
Hardwood
- most expensive philippine wood
- high grade furniture &cabinet
Narra
Hardwood used for posts and girders
Yakal and Guijo
Softwood used for panelings, sidings and furniture
Pine Benguet
Most common lumber in the market
- for framing, joists, trusses, nailers
Tanguile
For framings, chests, jewel boxes
White and Red Lauan
Has distinct dark grains. Hardwood for chests, jewel boxes and stair frames
Kamagong
Used for paneling and plywood veneer
- high grade furniture and cabinet
Dao
similar to pine, used for paneling
Almaciga
Used for saints
Baticulin
- reddish brown
- coarse texture
- medium grade beams, girders, rafters, chords, purlins
Apitong
Imported wood that is grayish brown to reddish brown. Has great wear resistance
Oak
Imported wood that has creamy white to reddish brown.
- heavy hard, strong and stiff: good shock resistance
Maple
Important properties for timber
1. S_______________
2. W_______
3. D_______
4. C_____
5. B____________
6. G___________
7. G________
8. F________
9.R_________to W_________ and I__________
- Strength and related properties of toughness, rigidity and hardness
- Workablity
- Drying properties and its tendency in Shrinking and Swelling
- Color
- Bending properties
- Grain structure and figure pattern
- Gluing properties
- Finishing
9.Resistance to Weathering and Insect damage
Grains running in the same direction
Straight grain
Grains in successive layer in opposite direction
Inter-locked grain
Constantly changing in orientation so that a line drawn parallel to their direction appears as wavy line
Wavy or Curly grain
Methods of Drying wood
1. N________
2. K_________
3. W________
- Natural Drying
- Kiln Drying
- Water Seasoning
Large sizes of those used for joists and beams
Timber
1 1/2 to 4 inches thick of wood
Plank
1/2 to 1 1/2 inches thick
Boards
Lumber is free from knots or sapwood
Clear
Lumber is planed smooth
Dressed, Surfaced, Sized
Lumber is planed on two sides
S2S
Lumber is planed on two sides and one edge
S3S
Lumber is planed on four sides
S4S
T&G
Tongue and groove
B.M.
Board measure
B.F
Board feet
Unit of measurement for lumber
Board Feet
L x W x THK(inch)
_______________________
12
Board feet formula
After the lumber is planed/ dressed
-5 = < 80 > = -10
Actual size of lumber
A piece of wood before S1S,S2S,S4S
Nominal Size
12 inches wide, 1 inch thick and 1 foot long
- nominal size of a dressed lumber
Board Foot
A straight- grained log is not sawn along its vertical axis
Diagonal Grain
Trees grow twisted, spiral-grained logs are produced. Fibers follow a spiral course with a twist that is either left or right handed
Spiral Grain
Board fibers run approximately parallel with the vertical axis of the log
Straight Grain
This type of grain results wen the direction of wood fibers has constantly changed
Wavy Grain
Board of this type has fibers at direction that are varying and irregular from the log’s vertical axis
Irregular Grain
Boards with this grain result from trees whose fibers lined up in opposite directions in each growth
Interlocked Grain
When wood is cut parallel to the grain direction and tangent to the growth rings
Plain/Tangential or Flat Grain
When board is cut parallel to the grain direction but through the radius of the growth rings
Quarter or Radial Grain
When board is cut across the grain
End grain
- most common method of sawing lumber
- produces the highest quantity of usable lumber
- shows flat grain on their faces and quarter grain on the edges
Plain Sawing
- cuts the log in quarters then slice each quarter into boards
- shows mostly quarter grain on their faces and flat grain on the edges
Quarter Sawing
- Sawing through and through
- shows mostly mixed grain - flat grain near the center of the face and quarter grain near the edges
Live Saw
- natural shrinkage of wood - seasonal checks, insects and fungal attack
- artificial defect- incorrect sawing or seasoning
Wood Defect
- softer, younger outer portion of a tree
-permeable, less durable, lighter in color - pores that permits liquid can pass through
Sapwood
- older, harder central portion of a tree
- denser, less permeable and more durable
- close and pocketed
Heartwood
Natural Defect:
Cracks or lengthwise separation across the annual rings of growth caused by irregular shrinkage during drying
Checks
Natural Defect:
Cracks between and parallel to the annual rings of the growth
Shakes
Natural Defect:
Irregular growths in the body of a tree which interrupt the smooth curve of the grain
Knots
Natural Defect:
Well-defined openings between annual rings containing solid or liquid pitch
Pitchpockets
Natural Defect:
The lack of wood on the edge or corner of a place
Wane
Natural Defect:
Caused buy the attack of fungi
Decay
Artificial Defect:
Planks hollow across the width of, may be the effect of incorrect piling.
Cupping or rounding
Artificial Defects:
Plank is curved like a bow along its length
Bowing
Artificial Defects:
Also called as edge-bend
Springing
Artificial Defects:
The long edges are straight but the diagonals are curved
Twisting or Winding
Plane surface of the piece caused by unequal shrinkage of the board
Warping
Lumber that is surfaced with a planing machine to attain a smooth surface and uniform size
Dressed Lumber
Lumber that is saw, edged and trimmed but not surfaced
Rough Lumber
Lumber that is 2”thick and less than 8” wide
Strips
- lessens the liability of the wood to be attacked by the fungi causing blueing and decay, and by some wood-boring insects
- reduction of weight
- increased strength
- minimum shrinkage
- reduced checking and warping
- increased nail-holding power of the wood
- improvement of the wood for the application of paint and receive wood preservatives
Advantages of seasoned lumber
- greater reduction in weight
- control of moisture content to any desirable value
- reduction in drying time
- killing of any fungi or insects
- less degrade (loss in quality during seasoning of the lumber
Advantages of Kiln Drying
Molave, ipil, yakal and etc.
Posts and other parts requiring strength and durability
Molave, ipil, yakal, guijo, apitong, bakauan
Post placed on top of concrete piers 30cm. Above ground lines
Yakal, narig, guijo, ipil, apitong
Beams, girders, rafters, chords, purlins
Applied to wood for its protection and enhance its grain structure, or its wood appearance
Wood finishes
Classifications of wood finishes
1. T_______
2. T_______
3. O______
Transparent
Transluscent
Opaque
Enhances the charm of natural wood grain
Transparent
Finishes that the wood absorbs; soaks into the wood to provide a natural feel
Penetrating Finishes
Wraps around the surface; a protective coat which seals the wood pores against harmful elements
Surface Coating
- Resin + Ethyl Alcohol
- forms a glossy film on the wood surface
- also called Japanning
Lacquer
- Oil + Resis
- resins are dissolved in oil or alcohol spirit
- natural: made from gums from plants, vegetable and insects
- synthetic: made from synthetic resin, or esterified glycerine
Varnish
- Lac flakes + Denatured alcohol
- spirit varnish
- lac flakes are secreted by an insect onto trees
Shellac
Type of finish may be achieved by boiling linseed oil or other oils
Oil Stain Finish
- transparent plastic finish made out of polyhydric alcohol esterfied with oleic linoleic, palmetic and fatty acids and mineral spirits
- moisture and oil free
- tough, hard, flexible finish
- highly resistant to dirt retention chipping, solvents, detergents, acids, hot and cold water
Polyurethane finish
Acids or chlorine are applied, these are called bleaching agents.
Bleach finish
Type of bleach finish that is:
- comparatively weak
- excellent for removing chemicals, dyes,ink, water stains from the wood surface
Chlorinated Laundry beach
Type of bleach finish that is:
- best bleach to use on natural wood colors
Oxallic Acid
Type of bleach finish that is:
-fairly expensive and extremely strong
- can bring out really light tones on dark wood
Two-solution bleaches
Contains oil plus natural synthetic resins
Oleoresinous Varnish
contains solvents plus natural synthetic resins.
* Shellac falls under this group
Spirit varnish
Made up of cellulose derivatives, resins, gums, volatile solvents as medium, softeners and pigments. Pigments may be introduced in the mixture in a wide variety of colors resulting to an opaque lacquer finish
Clear Lacquer
Achieved by brushing, rubbing or spraying processed fatty acids from animals and vegetables, mineral sources combined with alcohol.
Wax or Film finish
