Hi everyone here we talked about timber which is a building material and the things we talked about are advantages and disadvantages, manufacturing, classification with required tests. So if you have any questions or mistakes you can tell  Alirizgar234@gmail.com

1. 1| P a g e
Salahaddin University – Erbil
College Of Engineering
Civil Engineering Department
Timber
By
Neaz umer
Mahmud Rashad
Supervisor
Zrar sedeeq Othman
27 may 2019

2. 2| P a g e
Content:
1. Introduction…………………………………………………………………………………………….. (3)
2. Types or classification………………………………………………………………………….… (3)
3. Manufacturing………………………………………………………………………………………... (8)
4. Advantages and disadvantages…………………………………………………………... (10)
5. Mechanical and physical properties………………………………………………….. (12)
6. Required tests……………………………………………………………………………………..
7. References…………………………………………………………………………………………..

3. 3| P a g e
1. Introduction
Timber for construction is one of the many forest products used around the
world. It is used in buildings both large and small; here we consider timber for
the construction of buildings of six or more story's, and the biochemistry and
chemistry of wood modification that could enable much larger buildings. There
is ample global supply for the foreseeable future, and although there is a
worldwide trend towards deforestation, it is generally due to clearing land for
agriculture rather than logging for timber. Nevertheless illegal logging remains
a concern.
2. Types or classification
Timber is a type of wood which has been processed into beams and planks.
It is also known as “lumber” in US and Canada. Basically, timber or Lumber is a
wood or firewood of growing trees. Any wood capable of yielding a minimum
dimensional size can be termed as a timber or lumber. It is a stage in the
process of wood production. Timbers are used for the structural purpose.
Those woods which are adapted for building purposes are timbers. Finished
timber is supplied in standard sizes for the industry. Timber is used
for building houses and making furniture.
1. Bamboo
2. Birch
3. Cedar
4. Cherry
5. Mahogany
6. Oak
7. Walnut

4. 4| P a g e
1. Bamboo
Bamboo is a natural organic material. It is one of the most unique plants on
earth. Bamboo is grown in abundance in many parts of the world, especially in
tropical and subtropical regions. Most timber producing bamboos are from
South Asia. The color of bamboo timber is pale yellow to almost gold. It is an
industrial material also identified as the most promising building material.
Bamboo timber is an alternative to tropical hardwoods in recent years. It is
available in many forms.
2. Birch
Birch is a great craft-wood. It is an important source of hardwood timber.
Birch is of many types of like-yellow birch, white birch etc. Yellow birch is
commonly used which is also known as gray birch, or swamp birch. It is light
reddish brown color. Birch gives low natural luster.

5. 5| P a g e
3. Cedar
Cedar is a timber of high quality. It comes from several different trees known
as cedars. Where both strength and appearance of the exposed wood beams
are important, cedar is the only savior and perfect fit for this. It is used in for-
landscape, park, and garden structure. Its moderate strength and softness
make it unique. Cedar offers the advantage of the natural advantage. Basically,
it is a workable material.
4. Cherry
Cherry timber is grown as a tree plantation timber. Among different types of
cherry timbers, black cherry timber is the largest of the native cherries and the
only of commercial value. It is found throughout the Eastern United Nations. In
cherry timber, the grain is generally straight. It is a hardwood. It has medium
density and moderately durable. And used for small pieces of furniture's-
veneers, handles, cabinets, scientific instruments etc.

6. 6| P a g e
5. Mahogany
Mahogany is a high-quality timber. It is grown commercially almost in every
continent. Mahogany is widely used in the furniture and cabinet building
industry. It is made into plywood's and all kinds of trim. It displays hard grain. It
is one of the softest of all the hardwoods that are commonly in use. It is
moderate natural luster. The color of mahogany timber darkens with age. The
texture is medium and uniform. The price of this timber is in mid-range.
6. Oak
Oak timber is a type of hardwood from the oak tree. It has been used as
timber for thousands of years. It is straight grained. It is used for light
construction most of the time. Oak timber is used for -home ware, wine
barrels, firewood etc.

7. 7| P a g e
7. Walnut
Walnut is a premium timber. It is a specialist hardwood. The grain is straight
but it can be irregular. Walnut timber is really decorative. It carries a lot of
design for the interior. It has moderate natural luster. Walnut timber is
moderately durable. It is medium density.

8. 8| P a g e
3. Manufacturing
1. Felling
The first stage of preparing the timber for commercial use is called
‘felling’ - the process of downing individual trees. In this case, the
person cutting the tree is called the ‘feller’ - while the harvesting
machine is referred to as a ‘feller bunched’. A forestry worker will
determine when and which trees should be cut down, depending on
when they reach their economically ‘mature’ stages. Trees can range
from 40 to 150 years old before they stop growing vigorously and are
ready to be cut down. The differences in age at felling can depend on
the tree species. For example, conifers grow at a much quicker rate
than broad-leaved species. Environmental factors, such as soil
nutrients, can also affect their growth. Felling is normally carried out in
winter, because the trees usually have less moisture content in them,
compared to summer months, where they can have more than fifty
percent water content. Finally, felled trees should be replaced with
saplings so that the forest has a chance to grow once again, providing a
sustainable resource for future generations
2. Transporting
Next, the logs are stored in a clearing or in the forest until they are
needed at the sawmill. This also allows some of the ‘free’ water content
to evaporate, reducing the weight of the tree/log, which will result in
lowering the cost of transporting and handling. The trees are usually cut
into smaller lengths on-site and then picked up by a timber lorry, which
transports the timber to a processing site, such as a sawmill, paper mill,
pallet, fencing or construction producer
3. on Site
At the chosen site, the logs are debarked and bucked, or cut to
the required length. Then they are cut into boards, using equipment such
as circular saws and band saws. This is called ‘conversion’. The first stage
of conversion is a process called ‘breaking down’ - which means rough
sawing.

9. 9| P a g e
4. Seasoning
Seasoning of natural wood is the process of removing excess
water/moisture content. When a tree is felled, it still contains a large
proportion of water/moisture – usually between forty to fifty per cent
water content. During the seasoning process, a tree loses its free water
and a high proportion of its cell water and as a result, is less likely to warp
or deform.
Wood that has not been seasoned and still has high water content is
called ‘green wood’ and can be more difficult to work with because it has
a tendency to change shape.
5. Preparing for Market
After turning trees into timber through saw milling, covered in stage
three – also referred to as primary processing, the market value of
timber can be further increased through manufacturing sawn timber
products – called secondary processing. This involves the wood being
made (either by man or machine) into a more refined product, such as
a door, window or furniture, made to the specific size and dimensions.
At this stage any preferred treatments to timber such as fire or rot
resistance is added. Treated timber in sawn form is used either directly
in construction or to prepare construction components, such as timber
frame panels. Planed joinery components, on the other hand, are
usually treated after assembly. Finally, once all modifications are
made, the timber is ready to be shipped to market.

10. 11| P a g e
4. Advantages and disadvantages
Advantages
1. Excellent insulator: houses they are built out of bricks also
known to have outstanding insulating properties, but
timber manages to surpass them.
2. Timber is an elastic material: At the opposite of brick or
concrete walls, timber walls don’t need to be very thick. A
20m timber wall for example, is strong enough to protect the
internal space against the winter cold, in conjunction with a
proper treatment.
3. Easy and fast to build: a timber construction can be built very
easy and fast in contrast to a common brick or concrete
construction.
4. Sustainable: timber is a renewable resource.
5. Reusable: timber can be used more than once. It is easy to
recycle.
6. Price: to build a timber house or a timber construction is
cheaper than any other common procedure which has the
same requirements or sizes.
7. Weight: timber is very light.
8. Strength: Timber framings are strong in real structural terms.
9. Esthetic appeal: timber is a beautiful material for both
internal and external appearance.

11. 11| P a g e
Disadvantages
1. Shrinking and swelling: Timber has a natural ability to absorb
water which is also known as Hygroscopy
2. fire resistance: If timber has not passed a special treatment
which ensure a special fire rating, timber is highly
combustable
3. discoloration: With the time untreated timber which is
exposed to the different weather influences it discolors turns
to a dark and dirty optic
4. Moldiness: If timber is treated wrong or the installation is not
regulated accordingly, timber has the ability to mould.
5. Prone to abiotic forces: Abiotic forces of nature like Sun, Fire,
water etc. can have adverse effect on Timber.

12. 12| P a g e
5. Mechanical and physical properties
Physical properties
Specific Gravity (SG): Generally, specific gravity (SG) and the major
strength properties of wood are directly related. SG for the major usually
used structural species ranges from roughly 0.30 to 0.90. Higher
allowable design values are assigned to those pieces having narrower
growth rings (more rings per inch) or more dense latewood per growth
ring and, hence, higher SG.
Environmentally friendly: Timber is the most environmentally
responsible building material. Timber has low production energy
requirements and is a net carbon absorber. Timber is a renewable
resource. Well-managed forests produce timber on a sustained
continuous basis, with minimal adverse effects on soil and water values.
In plentiful and growing supply: Timber is readily available. Australia has
significant forest resources including a plantation estate covering more
than 1.6 million hectares, and the area is growing rapidly.
Safe: Timber has low toxicity and therefore requires no special safety
precautions to work with it, other than normal protection from dusts and
splinters. Timber frame construction requires little in the way of heavy
lifting equipment making building sites safer work places. Timber being
non-conductive has obvious benefits in terms of electrical safety. Modern
timber construction has increased fire resistance due to incombustible
linings protecting light frames.
Compression Strength: An important property of timber is that it should
have adequate compression strength to be used for different purposes in
construction industry.

13. 13| P a g e
Chemical Properties
A chemical property is a characteristic that can only be seen when the
material changes and a new material is formed. Examples of chemical
properties are ability to burn, ability to rust and ability to sour. So a chemical
property of wood is its ability to burn. When it burns, it gets hot and changes
toash.andThough, would is chemically inert as compared to other materials
but is affected by some acids and bases. Some species have proven very
useful for food containers (berry boxes and crates) because they are nontoxic
and impart no taste to the foods contained therein. Wood structures have
also found widespread use as storage facilities for salt and fertilizer chemicals

14. 14| P a g e
6. Required tests
1. TIMBER QUALITY LAB TESTING
Wood Research and Development specializes in wood testing,
wood species analysis, as well as new product testing and
development. These tests cover quality control procedures for every
part of lab operations; from staff training, equipment settings, and
proper reports. WRD lab locations produce correct and consistent
results for our clients by following these policies. Along with small-
scale testing of wood specimens, The static tests allow us to gain a
more accurate picture of physical properties for glue-laminated
timber and other composite wood products.
2. Small Strength Testing
We test the strength of our wood, and our samples, using a Tinnius
Olsen Testing Machine. This machine applies pressure, up to 60,000
pounds, on a sample of wood. We are able to test the strength of the
wood. Starting with light pressure, the machine begins to push against
the wood and slowly raises the pressure. This continues until a very
load snapping sound occurs and the wood breaks. The more pressure
the wood can take, the stronger it is. The machine has two testing
options for small and large timber.

15. 15| P a g e
3.Species Identification
The six softwood samples we take from the field inspection are put under a
microscope. By looking at the timber samples on a cellular level helps us to
find the species of the wood; hence the microscope. Knowing the species of
the wood, gives us a better idea of the health of the structure and how long
it will last. Once known, we begin to form a restoration plan for your
structure.
4. Large Strength Testing
Big Blue, our large beam testing machine, is used in our timber quality lab
testing. Pressure is gradually added until something breaks, similar to the
Tinnius Olsen machine. We use this to test our glue-laminated beams that
are layered with Kevlar, which is used to make bulletproof vests. Wood is
flexible and bends when pressure is applied but returns to its original shape
when taken away. As the wood bends, the Kevlar bends with it and helps
hold it together so even when wood breaks, if it did not split completely in
two, then it is still able to hold some weight.

16. 16| P a g e
7. References
1. https://woodrandd.com
2. http://www.internationaltimber.com
3. https://www.aboutcivil.org
4. https://civiltoday.com
5. https://be1341mortonw15036394berl.wordpress.com