Chapter 6 Alternative Construction Trends Flashcards
Previously, buildings used a ___________approach, but now use a ________ approach
Prescriptive
Performance design
Lightweight steel advantages: (5)
Reduced costs Significant weight reduction Ease of installation Resistant to termites and mold Non combustible to help satisfy codes
How thick is the steel used in LW steel construction?
1/8”
Components of a LW steel bldg:
C channel, H channel, sills, headers and joists
LW steel bldgs will get its strength from
The sheathing, usually OSB
Primary collapse concern for a LW steel bldg?
Floor collapse from a basement fire
Materials for ICF forms”
Cellular concrete
Cement bonded polystyrene beads
Cement bonded wood fiber (15%cement, 85%EPS)
Combo of 15%cement and 85% wood chips
3 ways to build and ICF wall
Flat panel
Post and Beam
Grid block
Flat panel ICF:
Most concrete and fire resistant
Low slump high aggregate concrete
Plastic or metal plates
80/20 concrete/EPS
Post and Beam ICF
40-60% concrete
Creates a P and B skeleton with some rebar
Grid Block
Legos with concrete in the middle
Least fire resistive
Least amount of concrete 20-30%
Fire concern for ICF
Though it’s supposed to not flame up, it will burn from fire around, causing pyrolization of EPS which is a petroleum product
Collapse concern for ICF
roof and floors,
Flat panel will hold longer than P and B and Lego blocks
What causes the strength in SIP panels
The synergy of being pressure laminated
2 types of straw bale buildings
Load bearing-Nebraska style
Non load bearing
How are straw bale buildings pinned together
Wire ties
Wood-bamboo
Sticks
Rebar
Two ways to compress a Straw bale bldg
Just the weight of the roof
Compression straps
Collapse threat of straw bale bldg
LW roof, especially Live roofs due to the load
Advantages of straw clay bldg
Durable Cost effective No special tools Green Good insulating Resistant to vermin, rot and fire
What’s the biggest fire concern for a clay straw bldg?
Contents
Roof and and ceiling collapse is possible
How much money has the ARRA allocated to Green building?
80 Billion fucking dollars
Challenges of Green Building and firefighting
Alternative power
Unusual dead and live loads
Low mass synthetics
Recycled or repurposed materials
Green building, like rammed earth brick, are efficient but can retain heat and products of combustion leading to
Flashover
How far apart are the parallel studs in double wall construction
3 1/2”
R value of or more
Gap allows horizontal extension of fire
When RSB sheathing is used for walls its applied with the foil side___________for roofs its_________
Out, inward
With 3/4” air space
Soil depth of extensive live roof
Of intensive live roof
2-4”, limited maintenance
1 foot, regular maintenance
4 elements of a live green roof
A building with strong roof system
Multiple membrane to protect the structure from water and drainage
A layer of soil
Planted veggies
Electrochromic Windows
Require 1 volt to change the amount of light reflected, but they are harder to break
How is AFM/OVE Green?
Reduced the amount of lumber waste
Reduces thermal bridging
Spacing for studs in AFM
19.5”-24” instead of 16”
Single 2x4 for top plate
Nailing boards for exterior siding are 2 X 2
How much less lumber does AFM use? Reduction in framing factor?
10 - 30%
15%- 25%
What is AAC
Auto claved Aerated Concrete
Made from Portland cement, gypsum, water, expanding agents and air
1/5th of wt of CMU
Mostly air
Other names for EWP
Manufactured board
Man made wood
Composite wood
How much more weight can an FiRP carry over a regular beam?
Twice as much
Homes are designed to give the occupants how long to get out?
15 minutes
