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Design Criteria
| Type |
Requirements |
|---|---|
| Multifamily and Commercial |
Design per IBC 2021 |
| One and Two Family Dwellings |
Design per IRC 2021 |
| Seismic Zone |
Residential: "A" Multi-Family and Commercial: use Code Central Seismic Design Parameters version 3.10 |
| Wind Load - Exposure "C" (3-second gust in miles per hour) |
Risk Category I: 100 MPH Risk Category II: 110 MPH Risk Category III: 115 MPH Risk Category IV: 120 MPH Residential: 110 MPH |
| Foundation Depth |
42 in. frost depth |
| Roof Snow Load |
Minimum design roof snow load after allowed reductions shall be 30 psf (i.e. Pf = 30 psf) For drift / unbalanced loading: Pg = 33 |
International Energy Conservation Code 2021 (IECC)
| Structure |
Default Values |
|---|---|
| Ceilings |
R - 49 |
| Walls |
R-21 or R-20 + R-5ci or R-13 + R-10ci or R-15ci |
| Floor over unheated space |
R - 30 |
| Crawl Space walls |
R - 15 - Continuous |
| |
R - 19 - Framed |
| Basement walls |
R - 15 - Continuous |
| |
R - 19 - Framed |
| Windows |
U - 0.30 |