Project Development And Documentation Flashcards
Statics
structures in equilibrium; sum of all forces and moments = 0
If forces are in equilibrium
Structure is considered statically determinate, which allows it to be assessed with simpler methods
Free Body Diagrams
Force magnitude depicted as vector lengths
Force direction depicted as a vector and angles
The free body diagram allows for a proportional and graphical representation of the forces acting on a component. The resultant or reactionary force direction and magnitude can be determined by directly measuring the resultants
collinear forces: added together
Coplanar forces: forces in the same plane
concurrent forces: pass through the same point, but not necessarily in the same direction
Nonconcurrent forces: forces do not pass through a shared point
reaction: force acting at supports int eh opposite direction of loads that keeps a component in equilibrium
Specialty loads
Loads such as those from HVAC equipment, a bathtub full of water, or a large suspended piece of artwork may require careful consideration for the particular area that the component is located in
Misc Loads
Loads such as wall-mounted shelving, cabinets, light fixtures, audio-visual systems, etc…
structural shapes
depth over width for increasing capacity
the center of a beam experiences the least amount of stress or strain; the center is considered the neutral axis. Placing more material at the outer ends of the beam (the top and bottom) is the most efficient use of material and weight since the material is acting where it is needed most, at the ares of most stress and strain. This is the reason why steel W sections are shaped the way they areL a slender wall at the neutral axis with maximum material at the extreme ends of teh section
Generally, beams mainly serve to handle loads placed on them vertically, Columns often must withstand lateral and direct axial loads. For these reasons beams are typically lighter and deeper and columns tend to be more of a square shape.
The Section Modulus, Moment of inertia and radius of Gyration describe the shape of a structural component
Material structural properties
the tensile strength, compressive strength, and modulus f elasticity (E) describe the material properties
Stress
Stress = Internal resistance to an external force
Tension: Pulling force (elongation and tearing)
Compression: Pushing force (crushing and buckling)
Shear: ripping or sliding force
Bending:
Stress: = force / area The nunit for stress is typically psi, ksi, or psf
Strain
Strain: deformation of a material (ratio of material change in length to original length)
Elastic limit: each material has an associated elastic limit that, when deformed due to a stress, the material will still return to the form and size when the load is removed
Inelastic Limit: material is loaded beyond the yield point when the material will deform permanently under the load, but not break. Also known as the plasticity of the material
Ultimate strength: Failure of the material, breakage
Design should work well within the elastic limit
Modulus of Elasticity (E)
Modulus of Elasticity (E) = ratio of stress to strain; E = stress/strain. Represents a material’s “stiffness” or its ability to withstand elastic deformation. “E” is unique to each material and is not based on the shape of a material
Once a material reaches its yield point, it is no longer in its elastic region - meaning, the material will no longer return to its original shape or size, but will begin to deform permanently. “E” does not apply to materials once they are in an inelastic state
* Units are typically psi (pounds per square inch)
Modulus of elasticity of these construction materials:
Brass - 100 - 125 GPa
Aluminum - 69 GPa
Concrete, High Strength – 30 GPa
Douglas fir wood – 13 GPa
Section Modulus
• Section Modulus = ratio of Moment of Inertia to the extreme fiber of the material shape from the neutral axis
• S = bd2/6 for square or rectangular sections
• Section Modulus directly related to the geometry, or shape of a material
Section Modulus: S=M/Fb or S=bd2/6 or S=l/c c = distance from neutral axis to extreme
fiber, M = moment, Fb = allowable extreme bending fiber of a material, b = width of material,
d = depth of material
Moment of Inertia (l)
Moment of Inertia (l) = stiffness of the cross-section of the shape
Relates the material’s shape and material distribution to an axis in section (typically the neutral axis
The maximum bending stress is at the top and bottom of beams; the more material at these points, the less the stress per unit area. Hence, the shape and efficiency of shapes such as steel W-sections. The more material at the maximum stresses, the more
“stiffness” that shape gives to resisting the forces
| = bd*/12 for square and rectangular sections
Bending and Deflection
Bending and Deflection
Bending: the tension and compression occurring in a structural member (think beam) that causes it to bend. Checking for bending is one of the most basic and common structural checks. If a beam is loaded and bends downward toward the center, the top of the beam is getting compressed, while the bottom is in tension because of the
“spreading” motion. If a beam is continuous over multiple support points, the beam may actually begin to deflect upward at the support points
Deflection: is the “sag” or change in position of a structural member. This is important to check so that deflection does not produce unwanted effects such as cracks in materials, visual unpleasantness, development of unwanted slopes, or cause pressures on materials not meant to be under load, like windows and doors
Whereas a beam, floor joist, or girder may be of adequate strength to support the load, the deflection may impact the serviceability or function of the system. For example, a slight flutter or “bounce” in a floor when walking can potentially be a failure in serviceability where an uncomfortable situation is created by lack of deflection control
Radius of gyration (r)
Radius of gyration (r) = column properties of Area and Moment of Inertia
Unless perfectly symmetrical, a column will have a weak and strong axis; failure in buckling will happen at the weak axis first (think W-section)
Effective length
Effective length = the total unsupported length of a column (L)
Typically adjusted with a K-value
> Both ends fixed, k = 0.5
• One end fixed, one end pinned, k = 0.7
> Both ends pinned, k = 1.0
> One end free, one end fixed, k = 2.0
Slenderness ratio =
Slenderness ratio = L/r
Associated with columns. The higher the ratio, the more prone the column is to buckling The taller the column, the more prone it is to failure in buckling, short columns typically fail upon surpassing the allowable stress of a material; P=F ÷ A
Basic Formulas and Applications
Basic Formulas and Applications
P= F=A ; P= pressure (stress) F = force A = area
• A common application may be for sizing a spread footing with a column supporting a certain floor area
Spread footing
Sizing spread footing example: by rearranging the formula above, you get A= + P; Area
of footing = Total Load + Allowable soil bearing pressure
Example: Column load supported by a concrete footing is 25,000 #. The allowable soil bearing capacity beneath the footings is 2,500 #/sf
•Area of footing required to not exceed the allowable soil capacity. Area =
25,000 # / 2,500 #/sf = 10sf footing required. A 3’-3” x 3’-3” will provide the
required surface area
The allowable bearing capacity is just one of the checks required to design a footing. For example, if the column is exerting a lateral load, then the sliding capacity of the footing may have to be checked as well as the potential uneven distribution of pressure across the footprint of the footing onto the soil
Strain
Strain: €=e/L (where e= change in length, L= total length of member)
Yield point
Yield point: the point where any more stress imposed on the material would cause the material to deform
Shear force
Shear force: V=wL/2 (where V=shear stress, w=uniform load on member, L=length of member).
By dividing in two, this gives the amount of shear force at each of the member, such as a beam based on a uniform load
Connections
Connections: Where there are 4 or more reactions, a structural member will be considered indeterminate
Pinned connection = resists X & Y load directions
• Roller connection = resists Y
• Fixed connection = resists X, Y, & Moment
• Candidate must understand how to find reactions for a beam
A reaction is the upward force at the beam supports resisting the downward forces
• Candidate must understand moment diagrams and how to find the moment of a simple beam
-Moment = rotation about a point caused by a force
• Moment is the Force multiplied by the Distance from point under consideration
Moment (M) = Force (P) x Distance (d)
• Resisting moment is the internal moment opposing the bending moment
• Neutral axis is the centerline of a structural member where no bending stresses occur
Halving the span or doubling the width of a beam…
Halving the span or doubling the width of a beam reduces the stresses by half. Doubling the depth of a beam reduces the stresses by a factor of 4
Kern area
° Kern area = is a central area on a column or foundation. If load resultants remain within the kern area, then the compressive loads will not develop a tensile stress. If a load or combination of loads causes the reaction to result outside of the kern area, the element will develop a tensile stress that must be resolved. Reactions outside of the kern area on a footing will indicate that there is unequal weight distribution or footing is not contacting the subbase at all locations
Pinned Connections
Pinned Connections
The majority of structural connections are typically designed as pinned or shear connections. Pinned connections typically handle the axial and lateral forces as shear forces. In the case of a beam to column connection, the capacity of the beam is considered individual from the capacity of the column. The forces imposed on the beam are then transmitted to the column as an axial load
These connections can be made a variety of ways depending on material. Nails, bolts, welds, clip angles, etc. can all be used to create a successful pinned or shear connection
Moment Connections
Moment Connections
Are used when it is beneficial to transfer the moment from the beam to the column and vice versa, such as in cases of buildings withstanding large lateral loads. Moment connections are also referred to as rigid or fixed connections
The connection is made with sufficient strength so that the beam and column (or other member) essentially acts as a single unit. It is anticipated that if a beam deforms due to moment, the column begins to react and deform as well
• For example, steel moment connections typically use web stiffeners, many bolts or welding, and fully engage the flanges of the beam and column
U Value
U value = 1 / sum of R values
U-value key points: Measures the rate of heat transfer Accounts for conduction, radiation and convection Based on various components and calculations Measures airflow The lower number, the more energy efficient a given assembly is. U-value is the mathematical reciprocal of R-value, U = 1/R.
Decibels dB `
decreases 6 dB for every doubling of distance
Specifications Methos
Descriptive
Specifies materials and methods without mentioning product (was used widely for a long time but takes long to write)
Performance
Specifies the required results
Proprietary
A specific product, ALlows open or closed (allows substitutions or not)
reference standard
specifies by established standards such as ASTM B 211 or ACI 318
Cost index for a city
(Index for a city A / 100) x National Average cost = Cost in City A4
Also
Index for a city A / Index for a city B = Cost in city A
Also
(Index for a city A) / 100 x National Average = cost in city A
SHEET TYPE DESIGNATORS
1-9
SHEET TYPE DESIGNATORS
0 General (symbols legend, notes, etc.)
1 Plans (horizontal views)
2 Elevations (vertical views)
3 Sections (sectional views, wall sections)
4 Large-Scale Views (plans, elevations, stair sections, or
sections that are not details)
5 Details
6 Schedules and Diagrams
7 User Defined (for types that do not fall in other categories,
including typical detail sheets)
8 User Defined (for types that do not fall in other categories)
9 3D Representations (isometrics, perspectives,
photographs)
LEVEL 1 DISCIPLINE DESIGNATORS
G General
H Hazardous Materials
V Survey/Mapping
B Geotechnical
C Civil
L Landscape
S Structural
A Architectural
I Interiors
Q Equipment
F Fire Protection
P Plumbing
D Process
M Mechanical
E Electrical
W Distributed Energy
T Telecommunications
R Resource
X Other Disciplines
Z Contractor/Shop Drawings
O Operations
Submittal revision
_ _ _ _ _ _ . _ _ _ . _
Div Code sub # Rev # (either number or alpha)
Characteristics of thermally Modified wood
Has lower chance of corroding metals
Closed systems under vacuum remove less moisture than open systems
open systems cause more internal stress
Made by a controlled Pyrolysis Process heated to 400 F changing chemical structure. Removes organic compounds making it no longer absorb water, expand or contract. Resistant to water, insects and decay. Process uses low oxygen so wood dont burn. Because no chemicals are used wood is less likely to corrode metals.
When wood is heated inside a closed system, wood moisture content is reduced to 5%. When in an open system, reduced to 0%, causing more internal stress
Common Divisions
Procurement and Contracting Requirements Group
Division 00 — Procurement and Contracting Requirements
Specification Group General Requirements Subgroup
Division 01 — General Requirements
Established administrative procedures for the project
Facility Construction Subgroup
Division 02 — Existing conditions of a construction site
Division 03 — Concrete
Division 04 — Masonry
Division 05 — Metals
Division 06 — Wood, Plastics, and Composites
Division 07 — Thermal and Moisture Protection
Division 08 — Openings
Division 09 — Finishes
Metal studs are typically specified as part of gypsum assemblies
Division 11 — Equipment
Division 14 — Conveying Equipment Facility Services Subgroup
Division 21 — Fire Suppression
Division 22 — Plumbing
Division 23 — Heating, Ventilating, and Air Conditioning (HVAC)
Division 26 — Electrical Site and Infrastructure Subgroup
Division 31 — Earthwork
Division 33 — Utilities
How many parts is each division section divided into
1. General (Unit Prices are located in Section 01 20 00 - Price and Payment Procedures)
Part 1 – General: Includes administrative activities, procedural requirements, and quality assurance guidelines. This includes quantities, distribution, and the responsibilities of each party in the supply chain, provided in expanded detail for the general conditions of the contract.
Part 1 sets specific requirements regarding materials and workmanship and specifies the requirements of what is to be submitted. For instance, it sets conditions for documents submitted to an architect for authorization of use, quality assurance, and the administrative requirements of mechanical insulation, i.e., installing thermal insulation on any mechanical system, including HVAC systems, ducts, boilers and piping systems.
2.Products
Identifies the specific product attributes and conditions of the product quality requirements. It describes the materials, products, equipment, and often manufacturing tolerances and testing requirements expected of the manufacturer. Part 2 also specifies where to find the descriptions of specified products or materials. Manufacturers must be clear in classifying products by name and product number in order to be clearly identified in the specification.
3. Execution Each Part is then further organized into a system of: . Articles . Paragraphs
Indicates special installation requirements and specifies how the products described in Part 2 will be used in the project. It stipulates the quality of workmanship required without dictating the contractor’s processes, yet stipulates the requirements of field quality-control testing. Part 3 contains product-specific provisions and explicit conditions for the installation.
Min. distance between doors swinging in the same directions
48” plus one door leaf
Hard vs soft E Coating
Hard Low-E Coating
A pyrolytic process produces hard-coated Low-E glass. It involves applying a thin layer of molten metal to a sheet of glass during the manufacturing process while it is still molten. As a result, the metal becomes welded to the glass, creating a highly durable (hard) attachment.
Best Uses for Hard Low-E Coating
The durability of hard Low-E coating means you can use them on storm doors and windows.
Hard Low-E Coating Pros
Option to accessorize: Because hard Low-E glass does not need sealants inside an insulated glass unit, you can accessorize the glass with in-between blinds, for instance.
Affordability: This coating option is cheaper than the soft Low-E glass since it does not require many layers.
Durability: The pyrolytic application of the hard Low-E glass means it is less likely to become scratched than soft Low-E glass. Consequently, it lasts longer.
Hard Low-E Coating Cons
High U Value: A high U-value means the optical thickness of a Low-E coating will increase. In other words, there aren’t very many layers of film present. Low-E coatings with hard surfaces are generally better suited to applications more concerned with durability than insulative or reflective properties.
Higher heat gain coefficient: Hard Low-E coatings have a higher heat gain coefficient. Allowing more ultraviolet light and infrared to pass through the glass allows a more significant heat transfer into your living space.
Soft-coated Low-E glass is formed using a process called Magnetron Sputter Vacuum Deposition (MSVD). In a nutshell, the particles used in the metal layer adhere to pre-cut glass sheets at room temperature. It takes place in an electrically charged inert gas-filled vacuum chamber, and the result is a metallic coating that is very thin and delicate.
Best Uses for Soft Low-E Coating
If energy efficiency matters more to you than durability, soft Low-E glass is for you.
Soft Low-E Coating Pros
High visible light transmission: Soft Low-E coating allows high visible light transmission, where light can filter through the glass and provide an unobstructed view of your surroundings. With this type of coating, you don’t have to worry about heat retention in your windowpane.
The specially designed coatings on soft-coated Low-E glass allows for effective solar control, preventing heat from entering your house during the summer and keeping it in during the winter months.
Ultra-low emission: The one significant advantage of soft Low-E coating is that it drastically reduces your energy bills. This is because soft glass has to be heated just before coating.
The glass surface that the coating uses absorbs the heat and retains it. That means that any other object or material placed near this surface will also absorb heat at a faster rate than its counterpart.
Less UV transmission: Another significant difference between soft and hard Low-E coatings is how much solar UV penetrates through them. While both sides of a soft Low-E coating can transmit solar UV, only the outer layer is UV transmitting. The manufacturing process protects the glass from solar damage, thereby strengthening its resistance. In places with intense sunlight, we see more people using glass as an exterior building material.
Soft Low-E Coating Cons
Fragile and less durable: soft coatings might be more pleasing to the eyes, but they are less robust than hard coatings.
Soft Low-E coatings can chip, crack, or peel easily on contact with anything thicker. The gutter will break over time if it comes into contact with anything more powerful than itself, like hail hitting your roof or people walking by on your pavement.
Soft Low-E coatings are thus not recommended for external applications.
More difficult to temper: The purpose of tempering Low-E coating is to produce a strong, durable, and safe film on your glass. However, soft Low-E coating is more difficult to temper because of its heat-reflection qualities. As a result, the installation process is more complex and time-consuming.
Cost: Soft low-E coating is generally more expensive because it is a fragile material that gets damaged. The installation process is complex and requires an experienced professional.
Atrium Code
404.3 Automatic sprinkler protection. An approved automatic sprinkler system shall be installed throughout the entire building. Exception: Where the ceiling of the atrium is more than 55 feet (16 764 mm) above the floor, sprinkler protection at the ceiling of the atrium is not required.
Section 907.2.13 A fire alarm system shall be installed in occupancies with an atrium that connects more than two floors
404.5 Smoke control A smoke control system shall be installed in accordance with Section 909. Exception: In other than Group I-2, and Group I-1, Condition 2, smoke control is not required for atriums that connect only two stories.
404.10 Interior exit stairways Not greater than 50 percent of interior exit stairways are permitted to egress through an atrium on the level of exit discharge in accordance with Section 1028.
1017.2 Exit access travel distance This table allows for a maximum exit travel distance of 300 feet for buildings equipped with a sprinkler system.
Thermoplastics Plastic materials
Thermoplastics Plastic materials used for piping are either thermoplastic or thermoset. As opposed to thermoplastics, thermoset plastics must be cured by heating or with a curing chemical to achieve permanent shapes. Once shaped, they cannot be reformed.
Copper temper
Beryllium copper
A strong copper alloy with high conductivity, elasticity, and tensile strength. It’s used in environments with high electrical current, corrosion, and elevated temperatures.
Cold rolled
A temper category for copper and copper alloys. Cold rolled copper is used in sheet and strip applications.
Annealed
A temper category for copper and copper alloys. Annealed tempers are designed to produce materials with specific mechanical properties.
Hot rolled
A temper category for copper and copper alloys. Hot rolled temper is similar to an annealed material and is generally only used for plate.
Mill hardened
A temper that’s heat treated to develop a strength level between fully heat treated and age hardenable tempers. Mill hardened tempers are used to create sturdy, miniature parts.
Drawn - general purpose (h58)temper
A temper used for general purpose tubes. It’s used when there’s no need for high strength, hardness, or bending qualities.
Oxygen free copper
A copper alloy with high conductivity. It’s used in electronics and manufacturing.
stairway width of occupant load higher than 49
According to the IBC, section 1011.2 Width and Capacity: “…The required capacity of stairways shall be determined as specified in Section 1005.1, but the minimum width shall be not less than 44 inches (1118 mm)… Stairways serving an occupant load of less than 50 shall have a width of not less than 36 inches (914 mm).”
Handrail code
According to the 2018 IBC, section 1014.3 Handrail Graspability: “Handrails with a circular cross section shall have an outside diameter of not less than 1 1/4 inches (32 mm) and not greater than 2 inches (51 mm). Where the handrail is not circular, it shall have a perimeter dimension of not less than 4 inches (102 mm) and not greater than 6 1/4 inches (160 mm) with a maximum cross-sectional dimension of 2 1/4 inches (57 mm) and minimum cross-sectional dimension of 1 inch (25 mm).”
Masonry Joints
Bed joint: This is the horizontal joint between two layers of masonry units, such as bricks or blocks. It is formed by the mortar that is laid between the units, providing a stable base and bonding them together.
Collar joint: This is the vertical joint between two wythes of masonry, formed by the mortar that is placed between them. The collar joint helps bond the two wythes together, providing stability and ensuring that the wall functions as a single, structurally sound unit.
Head joint: This is the vertical joint between the ends of adjacent masonry units, such as bricks or blocks, in a single wythe. Like the bed joint, the head joint is formed by the mortar that is used to bond the units together.
Where are air handling units located?
Near vertical distribution shafts
In all-air and air and water heating and cooling systems, one or more air handling units are typically located in one or more fan rooms. Although it is definitely appropriate to locate the fan room(s) near an exterior wall, it is of paramount importance to locate these spaces close to the vertical distribution shafts (that is, if we had to pick between these two locations). This will make the system more efficient as the horizontal distribution of conditioned air (heated or cooled) will be reduced. Apart from the location in plan, the architect and the mechanical engineer (and the owner might also have a say, because these rooms can take away a lot of valuable square footage) will work together to decide in which floor to place these rooms. Because the floor in which they are located does not have a major implication in terms of the efficiency of the system, other factors will have to be weighted, in order to decide the final location of such rooms.
How is mortar made
Mortar is made by mixing Portland cement, lime, and sand combined in different ratios to meet specific requirements.
R-Value
R-value measures resistance to heat transfer Based on a specific material property value Does not measure airflow The higher the number, the more energy efficient a given assembly is. R-value is the mathematical reciprocal of U-value, R = 1/U.
Landings at doors
According to the IBC, section 1010.1.6 Landings at Doors, “Landings shall have a length measured in the direction of travel of not less than 44”.”
Fire and smoke dampers
Fire Dampers - These are installed in ductwork where it passes through fire-resistant rated walls or floors. These devices are normally held open by a fusible link, which melts at a specific temperature, triggering the damper to close. By closing off the ductwork, fire dampers prevent the spread of fire from one compartment of the building to another, thereby maintaining the compartmentation strategy of the building’s fire protection system.
Smoke Dampers - While fire dampers are designed to prevent the spread of fire, smoke dampers are intended to control the spread of smoke, which can be just as deadly. Smoke dampers are usually controlled by a building’s fire alarm system and are triggered by smoke detectors. When smoke is detected, the damper closes, preventing smoke from spreading through the HVAC system. Combination Fire/Smoke Dampers - These dampers serve both functions, preventing the spread of fire and smoke. They close in response to a rise in temperature (like a fire damper) or when smoke is detected (like a smoke damper).
The importance of fire and smoke dampers lies in their ability to protect building occupants by preventing the spread of fire and smoke, thereby providing more time for people to evacuate safely. They also help to protect property by containing the fire, reducing potential damage. Regular inspection and maintenance of these dampers is critical to ensure they function correctly in the event of a fire, and many local codes and standards require such periodic testing and maintenance.
Plywood grading
Plywood grades range from A to D, with A being the highest quality and D the lowest. The first letter (in AB grade, for instance) indicates the quality of the face veneer and the second letter represents the quality of the back veneer. A cabinet of a high-end kitchen would require a high-grade plywood on both sides. AA grade is the best solution in this scenario, although AB would also be possible (but it is not given as an option).
BA Grade: BA grade plywood typically has a B-grade face veneer and an A-grade back veneer. The face veneer may have some noticeable patches, discoloration, or minor defects, while the back veneer is relatively smooth and defect-free. BA grade plywood is suitable for applications where appearance is important but slight imperfections are acceptable.
AC Grade: AC grade plywood has an A-grade face veneer and a C-grade back veneer. The face veneer is of high quality, with a smooth and uniform surface, minimal patches or defects, and an attractive appearance. The back veneer may have more noticeable patches or defects but is still structurally sound. AC grade plywood is commonly used when both sides of the plywood will be visible, such as in (non high-end) cabinet construction.
BB Grade: BB grade plywood features a B-grade face veneer and a B-grade back veneer. Both sides of the plywood have a relatively uniform appearance with some patches, knots, or small defects present. BB grade plywood is suitable for applications where appearance is less critical, such as subfloors, roofs, or non-visible areas.
AA Grade: AA grade plywood is the highest quality grade available. It features an A-grade face veneer and an A-grade back veneer, both of which are smooth, uniform, and virtually free from defects. AA grade plywood is used for applications where the highest level of appearance and quality is required, such as high-end cabinetry or furniture.
What is the purpose of bending a tie between an inner and outer brick wythe?
The purpose of a tie between an inner and outer brick wythe is to connect the two wythes and provide structural stability. These ties, often called wall ties or cavity ties, are used in cavity wall construction to maintain the alignment of the two separate wythes while also allowing them to act as a single, more stable structural unit. The ties also help in transferring lateral loads from the outer wythe to the inner wythe, increasing the overall resistance of the wall to wind or other lateral forces. Furthermore, in cavity wall construction, there is typically an air gap between the two wythes. A bend (or drip) helps with mitigation of water infiltration into the inner wythe, thus improving the overall moisture resistance and thermal performance of the wall
general rules for dimensioning
Always dimension toilet room drywall partitions from the toilet room side of the partition Always dimension corridor partitions from the corridor side of the partition For nonstructural elements, such as partitions, do not close dimension strings between structural elements
Project manual documents
Project manual is comprised of:
* bidding requirements
* contract information, including the owner-contractor agreement, bonds, etc. (Option A)
* general and supplementary conditions of the contract * specifications
Tooled, Troweled, raked mortar joints
Tooled mortar joints: In this method, the mortar is compressed and shaped with a jointer or a pointing tool after it has been partially set. A tooled joint is often used for its aesthetic appeal and its ability to create a watertight seal. The compression of the mortar during the tooling process increases its density, which helps to shed water, making it more resistant to weathering and moisture penetration. There are various styles of tooled joints, such as concave, V-joint, and grapevine, each providing a distinct appearance.
Troweled mortar joints: Troweled joints, on the other hand, are finished with a trowel, which is used to smooth and press the mortar into the joint as it is applied between the masonry units. The process is typically done as the masonry wall is being constructed. The troweled joint is generally a more basic finish, and it does not compress the mortar as much as a tooled joint. As a result, it may be less resistant to water penetration and weathering compared to a tooled joint.
Raked mortar joints: A raked joint is another type of mortar joint finish used in masonry construction. In a raked joint, the mortar is recessed or ““raked”” out to a certain depth (typically between 1/4 to 1/2 inch) from the face of the masonry units, using a raking tool or the edge of a trowel. This process creates a shadow effect, emphasizing the individual masonry units and giving the wall a more distinct and textured appearance. Raked joints are primarily used for aesthetic purposes, as they can create a visually interesting pattern or effect on the masonry wall. However, it is important to note that raked joints may be less resistant to water penetration and weathering compared to tooled or troweled joints. By recessing the mortar, raked joints can potentially allow water to accumulate within the joint, which can lead to increased moisture penetration and potential damage to the wall over time. For these reasons, this method is mostly used in interior applications.
Typical minimum operating pressures by fixture:
Typical minimum operating pressures by fixture:
Bathtub Faucet - 5 PSI
Sink Faucet - 10 PSI
Shower - 12 PSI
Urinal Flush Valve - 15 PSI
Waterproofing
There are many different approaches to structural waterproofing. The construction methods will in part contribute to the specification of types of waterproofing systems (positive or negative side) and may also determine the overall structural waterproofing strategy.
Structural waterproofing falls into 3 categories:
Type A – Barrier Protection
Type B – Structurally Integral Protection
Type C – Drained Protection
With 3 grades:
Grade 1 – Some water seepage and damp are tolerable depending on the intended use
Grade 2 – No water penetration is acceptable
Grade 3 – No dampness or water penetration is acceptable
From these categories we can offer designs based on:
Positive side waterproofing
Negative side waterproofing
Integral waterproofing
Integral waterproofing (Type B Structurally Integral Protection) is comprised of admixtures that are incorporated into the concrete mixture during the initial pour and are not usually seen as a “positive” or “negative” side waterproofing solution.
On some occasions, warranty providers may ask for two (2) forms of waterproofing, meaning both the positive and negative sides are offered protection
Positive waterproofing is applied on the side of the wall with direct exposure to water.
Negative waterproofing is applied from the opposite side, that is, from the interior where there is no exposure to the elements. This is generally used in remedial applications such as elevator pits. Negative side waterproofing in some instances has the capability of dealing with an incredible 13 bar pressure (this equates to just over 130m head of water)!!
Blindside waterproofing refers to waterproofing applied to the outside of the wall that becomes inaccessible after the wall’s construction. It is used in situations where the basement wall is supported by an excavation support system such as soldier piles and lagging, which are left in place.
