Roof
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Transcript of Roof
roof is the covering on the uppermost part of a building. A roof protects the building and its contents from the effects of weather.
Structures that require roofs range from a letter box to a cathedral or stadium, dwellings being the most numerous.
In most countries a roof protects primarily against rain. Depending upon the nature of the building, the roof may also protect against heat, against sunlight, against cold and against wind.
What is The Roof ???
Roofing Terminology Hip
The external angle at the junction of two sides of a roof whose supporting walls adjoin.
Joist In a flat roof, a horizontal structural member over which sheathing is nailed.
Rafter A structural member (usually slanted) to which sheathing is nailed.
• Flashing Sheet metal or other material used at junctions of different planes on a roof to prevent leakage.
• Gable The triangular upper part of a wall closing the end of a ridged roof
• Ridge The horizontal line at the top edge of two sloping roof planes.
• Valley The less-than 180-degree angle where two sloping roof sections come together
Roofing Terminology …… Drip
The strip of metal extending out beyond the eaves or rakes to prevent rainwater from rolling around the shingles back onto the wooden portion of the house.
Fascia Trim board behind the gutter and eaves.
Shingle Flashing Flashing that is laid in strips under each shingle and bent up the edge of a chimney or wall
• Underlayment The material (usually roofing felt) laid on top of sheathing before shingles are applied.
• Soffit The boards that enclose the underside of that portion of the roof which extends out beyond the sidewalls of the house.
•The history of roofing has come an extremely long way. Man has utilized various natural resources throughout history to create the environmentally safe, effective roofing of today. From wood, mud and straw, to tiling, shingles and beyond.
• As one can imagine, a roof can only be as good as the materials readily available, so every civilization had varying methods, tools, and materials for creating their respective roofs.
The roof of Pantheon doom
damp clay and earth on the roof of Greek temple
•Although most of the growth within the roofing industry has been within the last 200 years, the complete history of roofing starts much earlier than that.
•The Greeks and Romans were the first to experiment with differing roofing styles. The Romans introduced slating and tiling to Great Britain as early as 100 BC.
•Thatch roofs were introduced and implemented around the year 735 AD and it wouldn’t be for another 300 years until wooden shingles were first implemented as well.
Brief History of Roofing
until the 12th century that the history of roofing was changed under King John, when he issued a law in London that citizens had to replace their thatch and reed roof-coverings and replace them with clay tiles.
Dreadnought clay tiles began production in 1805 and industrial roofing at that time had little insulation but a good slope for rainwater and other debris. One hundred year after that, concrete tile roofing was first utilized.
Brief History of Roofing…..
While the history of roofing began to evolve In the southern parts of the United States, wood and metal were more widely used.
Even to this day, roofing styles are still based around wood and metal, It is hard to predict the future of the roofing industry and what technology can shape for the future, but for certain, the history of roofing has evolved and will continue to evolve forever.
Roof Types
• Flat • Shed• Gable • Hip • Dutch Hip• Gambrel• Mansard• Butterfly• Dome
FlatFlat A flat roof is not truly flat but angled slightly to allow for water runoff. It is the cheapest to build initially but will cost you much more than other roof types in maintenance costs.
Shed A shed roof is basically a flat roof with a slightly greater angle allowing for greater runoff. They are relatively easy to build and inexpensive as compared to most other roof types. They are usually used on home extension rooms and porches
Gable
Dormers are room construction extensions from the roof structure. They usually have windows or doors on the front wall structure. Dormers are often used in 1 ½ story construction to provide light and ventilation to the upper story.
A gable roof consists of two shed roof structures joined at the peak forming a ridge line.
Gable Dormers
Hip A hip roof is a gable roof with angled ends taking the place of the gable end of the structure.
Dutch Hip A Dutch roof design is a hip roof with small gable ends at the ridge allowing for attic ventilation
GambrelGambrel Gambrel roof design is similar to gable construction With two angles on each side. Steep lower surfaces and shallow angle top surfaces allow greater floor space in 1 ½ story construction
MansardMansard Mansard roof construction consists of a compound hip roof design with a lower and upper hip format.
ButterflyButterfly The butterfly roof is an inverted gable roof design creating a central valley for runoff. The design is visually stunning but impractical for water tightness.
DomeDome
Dome construction is one of the most difficult to build but is often the most interesting visually
Geodesic roof construction consists of triangular framing placed together to form a dome. These structures have surprising strength and visual interest.
GeodesicGeodesic
Types of roof structureTypes of roof structure
Flat roof
Pitch roof
Space frame
Roof shell
Folded plate
Tensile structure
1. Flat roof A roof is designated as flat if its
slope is less than ten degrees. Slope less than 3:12 or 25 percent
Flat roofs have traditionally been used in hot climates where water accumulation is not a problem.
Structural decks ordinary used Wood panels over wood joist Solid wood decking over heavy
timber framing Corrugated steel decking Sitecast concrete slab Precast concrete slab Panels of wood fibre bonded
together with portland cement etc
ELEMENTS OF FLAT ROOF
Concrete gutter Steel decking
parapet
Lines indented for expansioncaused by heat and easy to flattenthe roof in a uniform manner to prevent any pool of water after rain.
concrete
Water pool formed due topoor workmanship
PROBLEMS OF LEAKING ON FLAT ROOF
Weatherproofing the flat roof The flat roof relied on some kind of membrane for keeping
moisture out. In dry climates this is done with clay tiles, but in Canada asphalt, or rubber is necessary.
CONCRETE, TIMBER OR STEEL STRUCTURE
Waterproof layer and insulation
Cement screedFinishes
Flat roofs are never actually flat, a subtle slope directs standing moisture to drains at edges, or inside.
Advantages Disadvantages of Flat roof Advantages Disadvantages of Flat roof Design:Design:
Advantages: No space lost below roof, i.e. no dead space Less material is used than in a sloped roof The rooftop is potentially useful as a terrace, or sleeping porch Potentially pleasing appearance Easier to build than a sloped roof
Disadvantages: Roof elements can not overlap, hence waterproofing must be
more complex, and more thorough Drainage is not automatic Support of snow load must be insured
Pitched Roof
pitched roof is a roof structure where the roof leans to one side of the house. It is also known as lean-to roof. The rafters are connected to the highest wall and then it is inclined to a lower wall, which then forms the pitched roof.
The rafters are often connected into the wall individually or even supported on a wall plate bedded within the wall.
This type of roof can have no joist at all or have a tie or have a joist with a strut to give more strength.
column
wall
columns
walls
A mono-pitched roof structure
A lean-to roof structure
A pitched roof
Pitched Roof Types
column
wall
flashing
openings
SUNSHADING
flashing
The Components
Roof Framing Plan
Terminology
Roof Terms
PITCHED ROOF
TIMBER O
R STEEL RAFTER
Waterproofinglayer andinsulation
Timber batten
Finishes:Clay tiles orCement tilesMetal decking
Ceiling
Calculating Pitch
Roof with a pitch of 3:12 (25 percent) or greater called Steep roof
PITCHED ROOF: TIMBER - trussSTEEL - truss
Truss built as from individual members
Truss fabricated from factory
Truss fabricated from factory
Whole roof structure built fromsteel
Gang nails
steel
rivetted
Placement of roof clay tiles as seen from below
ROOF FINISHES
ATTAP
CLAY ROOF TILES
PATTERNED CLAY ROOF TILES
PATTERNED STEEL DECKING 1
PATTERNED STEEL DECKING 2
ASBESTOS
A space frame or space structure is a truss-like, lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames usually utilize a multidirectional span, and are often used to accomplish long spans with few supports. They derive their strength from the inherent rigidity of the triangular frame; flexing loads (bending moments) are transmitted as tension and compression loads along the length of each strut.
3. Space frame
4.Dome4.Dome A dome is a structural element of architecture that resembles the hollow upper half of a sphere. Dome structures made of various materials have a long architectural lineage extending into prehistory.
A thin shell is defined as a shell with a thickness which is small compared to its other dimensions and in which deformations are not large compared to thickness. A primary difference between a shell structure and a plate structure is that, in the unstressed state, the shell structure has curvature as opposed to plates structures which are flat
4. ROOF SHELL
Its an roof which has been moulded to an shape. which is in rcc, steel etc.its for large covering for open spaces
5. FOLDED PLATE ROOF5. FOLDED PLATE ROOF
A tensile structure is a construction of elements carrying only tension and no compression or bending. The term tensile should not be confused with tensegrity, which is a structural form with both tension and compression elements.
6. Tensile structure
The CribPost SystemThe CribPost System
Main FeaturesMain Features
CribPosts can be extended to any desired elevation.
CribPosts can be clustered to obtain higher lifting capacities.
The roof is monitored by laser instruments to maintain close tolerances.
Lateral stability is maintained and adjusted through ROOFLIFTERS’ unique guying system.
The entire roof can be lifted in a single section using ROOFLIFTERS’ multi-point synchronization system.
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The CribPost System is best described as a series of temporary hydraulic shoring posts that can be continuously extended with the intent to lift a roof to a higher elevation.
Green Roofs Look
Something
Like This
What Are Green Roofs?
A green roof is a roof of a building that is partially or completely covered with vegetation and soil, or a growing medium, planted over a waterproofing membrane.
It may also include additional layers such as a root barrier and drainage and irrigation systems.
also known as vegetated roof covers, eco-roofs or nature roofs. water quality by filtering, absorbing or detaining rainfall. Green Roofs Are Great for These Things ,great for the environment.
On the green roof of the Mountain Equipment Co-op store in Toronto, Canada.
Green Roof Types
Green Roofs
Rooftop Garden Rooftop Garden Edge RestraintEdge Restraint
RooftopRooftopGarden Garden AnchorAnchor
RoofRoofSystemSystem
ComponentsComponents
Rooftop Garden Edge Restraint A rooftop garden edge restraint that supports green roof
media while allowing water to drain cleanly under paver systems on pedestal / tabs where no internal drains are present and allows water to scupper while holding back media / aggregate while serving as an independent border.
Roof Top Garden Anchor
Rooftop anchors provide an efficient and economical way to secure blanket components. While conventional ties require the patience and manual dexterity of laborers, the innovation of the GRS Rooftop Anchor greatly improves effectiveness when installing rooftop mats.
Roof System Components Filter fabric, moisture retention mats, root barriers, drainage
components, inspection chambers, separation fabric, media, wind erosion blankets, plants, and bio-trays. Green Roof Solutions has all of your rooftop garden and green roof systems components.
Green Roof Case StudyNegotiated with the building owner to retrofit section of roof.Roof needed to be replaced.
Environmental benefits – stormwater mitigation, building insulation, urban heat island mitigation, and aesthetic improvement.
Conducted structural engineering analysis to make sure building structure could hold weight of saturated soil. The existing ballasted roof (stone) was about the same weight as the green roof.Planted with six types of sedum.
1. Insulation Layer
Reused styrofoam insulation that was on roof.
2.Water Barrier
Water Barrier is most important part of the roof, and is installed the same way as for a standard roof. No Leaks!
3.Waterproof Testing After waterproofing
store 2 inches of water on
the roof for 48 hours to
test barrier.
4. Root Barrier Root barrier is thick plastic, and prevents roots from penetrating the waterproof layer.
5. Water Retention Root barrier sealing and water retention layer. Water retention layer stores water in small “cups” for use by plants after rain event.
6. Soil Placement
Install filter fabric beneath soil, so not to clog water retention layer. Specially engineered, highly inorganic soil (very little humus) with high water absorption capacity.
7. Soil Layer
Spread soil to consistdepth – 3 inches.
8. Wind barrier
Cover soil with photo-degradable wind barrier to prevent wind erosion.
9.Planting the Roof
Plant through the wind barrier with sedums, low-lying, hardy, water-retaining plants that thrive in harsh environments.
Select several varieties based on blooming, color, etc.
Planting CompleteOctober 2003
One year after planting September 2004
Green Roof May 2005
