PROGRAMMING + ANALYSIS Flashcards
(87 cards)
Gross floor area
In matters of code, gross floor area is measured from the inside face of exterior walls. In other matters of programming and analysis (programming, pre-design, schematic design, or cost estimating), gross floor area is measured from the outside face of the exterior walls. It is a value used in the denominator of economic efficiency proportion measures like “net-to-gross” (interior area, excluding corridors, lobbies, elevators, bathrooms, and stairs, divided by gross floor area). “Usable area,” is like net area, except that it includes corridors. “Rentable area” is like usable area, except that it includes bathrooms and lobbies. “Grossing factor,” is rentable area, divided by usable area. To make these concepts even more difficult to remember, their specific definition varies somewhat by region and industry, so you might have correctly heard one of these terms used in another way. Argh. Try not to stress and do your best based on these definitions.
Catchment areas
In a discussion of stormwater runoff, the catchment area is the region from which rainfall flows into a stream, culvert, catch basin, or roof drain.
The field of building feasibility study reappropriated the phrase “catchment area” from the stormwater people as a useful parallel. It is the region from which residents are expected to visit your building. When siting a school, how many children live in an area bounded by the midway points between your site and other schools? When siting a hospital, what proportion of residents within X miles are over the age of 70 and how many of them have health insurance? For your proposed indoor pool site, it is unlikely that residents will drive past another, more proximate, indoor pool to visit your spot further away. Your proposed corner store will have a catchment area of no more than six blocks because it relies on pedestrian customers. In this way, to judge the feasibility of building here, we’ll map a catchment area based on demographics, commerce, geography, and human habit to describe the area from where your building will draw people
Where is the most effective location for an outdoor noise barrier?
If you have a noise source (truck) and a receiver (person with ears on a balcony), the least effective place for an outdoor noise barrier is halfway between them. The most effective location is as near as possible to the noise source or as near as possible to the receiver. The image is from my book, Architectural Acoustics Illustrated (Wiley 2015)
What is a population pyramid?
Graphic representation of populations showing both age and gender. helps visualize populations as they grow older and new generations fill in the bottom of the pyramid, with the older generations dying off and allowing for the next generation to be the top.
Positively- and negatively- pressurized locations in a building with open windows
positive pressure on windward side and negative pressure on leeward.
“Ideal” structural parti for seismic design
Uniform loading of structural elements (stress connections from non-uniform loading– for instance, cantilevers– are weak points in an earthquake)
Low, wide buildings (prevents overturning)
Equal floor heights (means fewer stress connections)
Symmetrical plan shape (minimizes torsion/twisting)
Shear walls or bracing at the perimeter (more efficient at resisting torsion/twisting than shear walls in the core)
Short spans (less stress on members and more columns provide redundancy if some are lost in an earthquake)
Minimize openings in floors and roofs (more efficient diaphragms)
Extend shear walls continuously from roof to foundation
Why avoid cantilevers, irregularly-shaped buildings, re-entrant corners (L- or T- shaped plans) when designing in seismic zones?
There are two reasons to avoid re-entrant corners (and other irregularly-shaped buildings) in your parti:
First, like any irregular shape, they produce differential motions between different wings of the building, stressing the re-entrant corner (interior notch)
Second, these shapes create torsion in the building that is difficult to predict
The problem with re-entrant corners in earthquakes
Each portion of the building twists out of phase with the other
Solutions for the reentrant corner problem in seismic design
Separation, strengthening, or stiff wall elements
Irregularly-loaded buildings and seismic failure
Failures in earthquakes from:
Soft story problem (tall first story with slender columns and not much lateral bracing). This issue, top row, is the most common and causes the most death and destruction.
Weight irregularity (More weight in the top floor, shown in red)
Shear wall doesn’t extend full height of the building
Shear wall not continuous over full height of the building
One story weaker than the others
Jutting building elevations:https: //www.nps.gov/tps/images/briefs/41-cover-image.png
When the shear wall is overly-perforated with apertures or doesn’t continue uninterrupted all the way from roof to foundation:
When the shear wall is overly-perforated it fails to bestow the benefit of a shear wall. It no longer protects the building from failure under a lateral load like an earthquake
Can foundations bear on loam?
Yes, loam can support a building. It is a combination of sand, silt and clay.
Gravel, clay, shale, sand are okay; rock (bedrock, limestone, sandstone) is great for supporting foundations of heavy buildings.
Organic soil and peat (dark brown or black and easily compressible) are not competent soils.
What is the difference between a Phase I and Phase II Environmental Site Assessment (ESA)?
A Phase II ESA is more thorough than a Phase I ESA.
Any property owner, regardless of fault, can be held liable for releases of hazardous materials from their land. However, if you purchased a property and can prove you performed appropriate environmental due diligence, but found no environmental red flags before the purchase, you are granted protections from that liability should toxic sludge be found later to be leaking from your land into the river. The Environmental Site Assessment (ESA) has become an established standard for this type of before-you-purchase-land environmental due diligence, and is used by the buyer and lender to both assess risk and protect from future litigation.
A Phase I ESA includes site inspection by an environmental professional, a historical records review of the property, and interviews with owners, occupants, neighbors, and local government officials. If a Phase I ESA turns up a recognized environmental concern (REC), then the environmental professionals conducting it will recommend a Phase II Environmental Site Assessment (ESA).
Unlike a Phase I ESA, a Phase II ESA is invasive, involving soil testing, groundwater sample testing and testing of building materials.
Best location in a warm climate? Best location in a cold climate? (Site A:North of river or Site B South of river)
Site A: cold climate, water provides clearing and solar reflection for solar gains
Site B: warm climate trees to south provide shade in summer.
Body of water provides clearning for direct (and reflected) southern solar gains
Site A: best location in a cold climate
According to the building code, a courtroom has an occupancy classsification of _______ . (You may use the Amber Book Case Study material or the internet to look this up.)
Assembly (A)
Business (B)
Institutional (I)
Mercantile (M)
Answer: a courtroom is classified as Assembly (A).
See a list of code occupancies here. In the exam, you’ll want to be sure to use the search function to find the appropriate occupancy: in this case you’d search for “courtroom” and find it under occupancy classification A-3. These four classifications—Assembly, Business, Institutional, Mercantile—plus Educational (E), can mislead you if you try to guess instead of search. For instance, a medium-sized university lecture hall is not considered Educational, it is Assembly instead—Educational occupancy is reserved generally for K-12. A bowling alley, funeral parlor, and restaurant seem like they’d be Mercantile, but the code also considers them Assembly spaces—Mercantile is reserved for places where things are sold, like markets or department stores, without the density of a restaurant. You might assume that museums and libraries are Institutional occupancies, but they are also Assembly—Institutional as an occupancy is not about government and civic institutions, but rather for buildings like hospitals and jails where people may not be able to leave on their own in a fire. Generally if your building has a high density of visitors, it may be an Assembly occupancy, even if it doesn’t feel like a theater or banquet hall. Business occupancy includes spaces for lawyers and architects where people work every day (and know their way out if the lights fail and the corridor fills with smoke).
According to the building code, a bank has an occupancy classsification of _______ . (You may use the Amber Book Case Study material or the internet to look this up.)
Assembly (A)
Business (B)
Institutional (I)
Mercantile (M)
Answer: a bank is Business (B) occupancy.
Why is a bank, post office, or barber shop considered a Business and has the B classification—while a courtroom is considered an Assembly, and has the A classification? They both have papers in storage and visitors. I suppose some threshold of people per square foot is crossed when you move from bank to courtroom on the density scale. In any event, that is why when faced with this kind of question on the exam, you’ll be sure to search the case study for “bank.” Don’t memorize these; use the search function instead because occupancy questions will almost surely come within a case study, and even if they don’t come in the case study section, you can often still look up the answers later in the case study section.
You are designing a health clinic in Zambia on a remote site. A well is not an option here, so water will be delivered to a tank. No pump will be used in the building’s plumbing because the clinic is off-the-grid and only has power through photovoltaic panels on the roof. The pressure at the faucet is not sufficient. This can be best rectified by _______.
Increasing the diameter of the pipe
Increasing the height of the water storage tank
Swapping out for a larger tank with a larger diameter
Utilizing pressure-increasing valves
Answer: Increasing the height of the water storage tank
Building foundations should rest on _______.
Shallow soils in temperate climates (less than 2 feet deep)
Peat
Sand
Topsoil
Answer: Sand
Peat and topsoil are organic, so they are unstable. In temperate and cold climates, foundations should rest below the frost line, typically more than two feet deep. Sand may not seem stable, but it is! If you’ve been to the beach, you’ve almost certainly seen hundreds of buildings supported by sandy soil. This house is on friction piles (telephone poles driven into the ground); this one is likely on a spread footer concrete foundation.
Can you build on a floodplain?
A 25-year floodplain encompasses the area, usually adjacent to a body of water, that has a one-in-25 chance of flooding this calendar year. This is different than the “It floods every 25 years,” misconception because it may flood here twice in one year and then not flood for 90 years, and that’s normal. Likewise, a spot in a 100-year floodplain has a 1-in-100 chance of flooding this year. Most building and zoning regulations are based on a 100-year-flood event.
The National Flood Insurance Program was created by the federal government and administered by FEMA when it became clear that flood insurance couldn’t be effectively offered by the private sector: too much financial risk in the event of, say, all of Houston flooding in a single hurricane event, or all of Los Angeles in a Tsunami, where the insurance company wouldn’t have enough cash reserves to cover the damage to everyone. FEMA, then has requirements should you choose to build on a floodplain. As you may imagine, the rules are complex, but generally new and substantially-renovated buildings must be built such that your lowest floor sits above base flood elevation (BFE). You can find the BFE of your site by studying FEMA maps, and you can get your lowest floor above BFE on piles, on a crawlspace, or on fill. If you build on a floodplain, the feds may require you to purchase flood insurance.
Provided you get your lowest floor above base flood elevation, most municipalities will allow you to build within the 100-year floodplain, but some disallow construction within the 25-year floodplain.
What is the building efficiency ratio of an office building with 100,000 sf, given that 20,000 sf is dedicated to elevators, physical plant equipment, restrooms, hallways, lobby, and the building management office
Answer: 80%
The leasable space, divided by the total space, returns the building efficiency ratio. As you may imagine, this number varies by project, is largely controlled by the architect, and often determines whether a development is profitable.
In your own words, what is net present value? Provide an example.
You have a choice between two systems: System A has a lower installation cost, but B has a lower operating cost because it is more energy-efficient. Net present value, a technique in life-cycle cost analysis, allows you to easily compare the total cost of the two choices because the cost of installation, plus operation, of each choice is translated to today’s dollars. It accounts for inflation (saving a dollar in energy bills in five years is worth less than saving a dollar today in construction cost); it accounts for compound interest (if we save a dollar today, we can invest that dollar over the next five years to earn a return); and aside from energy costs it often accounts for maintenance costs and how long each choice is expected to last before a replacement is needed. It is the easiest concept to own in life-cycle cost analysis because the spreadsheet will tell you that, for instance, Curtain wall System A, over the next 20 years, will cost 10 million in today’s dollars and Curtain wall System B will cost 12.5 million, also in today’s dollars. In this example, the less expensive system to install (but the more expensive system to operate) has the lower total cost over time. The savings in energy use is not enough to make up the difference in construction cost.
Identify the following standards:
ASTM E 1527
ASTM E 1903
ASHRAE 55
ASHRAE 62
ASHRAE 90.1
To hold unscrupulous people making false claims about building performance accountable, to standardize measurement conditions so that we can accurately compare performance from one building to another, to establish a baseline used for clearing code, LEED, or a similar third-party hurdle, and to facilitate a common language in courtroom proceedings, organizations like ASTM, ANSI and ASHRAE create and maintain standards. If you are exploring environmental performance as it applies to the ARE exam, you’ll want to take a minute to memorize which of these standards measures what.
STM E 1527: Phase I Environmental Site Assessment. Often required in commercial real estate before a bank loans money to develop a site, environmental engineers will attempt to determine if there is asbestos, lead paint, contaminated soil, etc. Phase I is a cursory evaluation, involving a walk-through, interviews with occupants, inspections of adjoining properties, and review of government records pertaining to the site. Was there a dry cleaner or gas station nearby that might have contaminated the soil? Does that pipe insulation look to be of an age that indicates it may have asbestos?
ASTM E 1903: Phase II Environmental Site Assessment. A more in-depth analysis often required if Phase I turns up a red flag. In Phase II, soil samples are taken; pipe insulation sample is taken to a lab.
ASHRAE 55 Thermal Comfort. Cited in LEED, this establishes ranges for temperature, humidity, airspeed, and thermal radiation as it relates to the clothing and activity of the occupants. It’s easier to achieve low energy use if you allow the building to get too warm or too cold, so requiring that it meets ASHRAE 55 keeps the energy modeler honest.
ASHRAE 62: Ventilation and Indoor Air Quality (IAQ). Also cited in LEED. Establishes just how fresh “fresh air” must be, establishes required outside air ventilation rates, etc.
ASHRAE 90.1 Energy and Lighting. Also cited (and cited often) in LEED, this checks greenwashing by owners, architects, and energy consultants. It establishes minimum performance for Energy Use Intensity (EUI), which measures annual kBTUs-used per square foot of floor area. Recently, buildings are publishing their EUI, even in design publications and design awards announcements. Understanding EUI isn’t a big part of these exams, but is becoming important to the profession. For instance, a warehouse has a median EUI of about 25 kBTU/sf (not much lighting or equipment or need for occupant thermal comfort. . . and spread over a large space). An office or school is 50, a mall is 100, a grocery store or hospital is 200 (lots of equipment), and a fast food restaurant is 400 (lots of equipment in a small total floor area). The goal then is to get your building well under those industry averages to drive down societal energy use.
*The standards on this list primarily apply to mid-sized or large buildings.
Historic preservation and sustainability: this unfolds generally as common sense would dictate. Form a team with members that have a preservation background and members that have a sustainability background. Identify methods to reduce energy use, but consider the impact on the historic building. Execute what is needed to meet energy performance goals, but start with that which is least likely to denigrate the historic nature of the building. Only engage the disruptive technologies after you’ve engaged the less-disruptive ones.
Begin with the least invasive, most cost-effective, weatherization measures. Address air-tightness before adding insulation. Insulate unfinished spaces (attics, basements, crawl spaces) first, then only if the energy model deems it necessary should you remove historic plaster and trim in finished spaces to insulate there. Weather stipping and caulking windows is acceptable, as is installing storm windows. Don’t, for instance, remove a historic, durable, heart pine floor and replace it with a bamboo floor because the bamboo flooring seems to be sustainable. Use solar only after other less-intrusive options have been exhausted.
Please don’t run a wire like this person did!
When upgrading the heating and cooling systems, use the least invasive strategies first: smart, programmable thermostats and ductless HVAC systems that use refrigerant or water pipes instead of ducts. If you require ducts, route them away from important spaces and better to expose them if concealing them requires ripping out important historic finish materials. Don’t position outdoor HVAC equipment where it can be seen. (Consider a geothermal system, which is efficient and has no visible outdoor equipment.)
Retain the roof’s character if it is visible, typically the case in sloped roofs. . . but if the roof is low-slope (“flat”), feel free to install a green roof, high albedo membrane, or cool roof technology.