Hazard Resistance

Claudette Reichel  |  6/27/2008 12:03:22 AM

Multihazard Resistance

General:

__  Emergency back-up power system

__ Easy access shut-offs

__ Emergency kit storage

__  Multiple escape exits

Flood Damage Reduction

Built above anticipated flood levels:

In noncoastal A zones, floor is above BFE using one of these
      foundation types:

__  Slab on compacted fill, extending max. 2 ft. beyond house footprint

__  Slab cap on compacted fill within a stem wall foundation

__  Unfinished, floodable crawl space with flood vents

__  Pile, post, column or pier open foundation; enclosures vented or
     designed to allow entry and exit of flood water

In V zones and coastal-A zones, lowest horizontal structural
     member is above BFE with:

__  Continuous pile, open foundation

__  No or minimal obstruction as allowed by local ordinance

In areas of minimal risk (Zones C and X) near A or V zone property:

__  Lowest floor is above BFE of nearest flood zone

Additional design features:

__  Decks, porches built and anchored to resist flood forces

__  Garage above BFE or includes flood vents if below BFE

__  Garage floor, patios, etc. min. 4 in. below living floor

__  HVAC, electrical, mechanical systems elevated above BFE

Additional flood protection features:

__  Backflow valve in sewer line

__  Flood-resistant materials and assemblies on first floor (drainable,
     cleanable, dryable)

__  Appliance styles, installations that minimize damage in shallow
     floods

__  In areas protected by levees, designs and materials that are
     submersible, drainable and easily flushed

Hurricane and Tornado Resistance

(See wind design speed map and associated wind-resistant building code for specific requirements; checklist below includes general guidelines for hurricane zones.)

General features:

__  House is < 60 ft. long

__  No more than two stories (levels)

__  Wall height of each story is < 10 ft.

__  Exterior cladding (siding, roofing, etc. rated for wind design speed)

__  Reinforced safe-room within house

__  Storm storage for outdoor items

__  Outside accessories securely anchored

Walls:

For wood frame construction:

__  2x4 studs spaced 16” o.c., or 2x6 studs spaced 24” o.c.

__  Bottom plates anchored to foundation

__  All load-bearing studs anchored to bottom and top plates with metal 
     hurricane connectors or structural sheathing with load-specific
     nailing pattern

__  Upper story anchored to lower story

__  Structural sheathing or inset shearwalls to meet shear load
      requirements

__  No windows, doors near corners

__  Corner hold-down hardware at ends of each shearwall

For masonry construction:

__  Rebar connects foundation to wall (4-ft. spacing typical)

__  Rebar reinforcement full height of walls

__  Vertical rebar reinforcement at corners and both sides of windows
     and doors

For SIPS, ICF, Shotcrete and other building systems:

__  Engineered for wind speed of local wind zone

Roof, Overhangs and Attachments:

__  Wind rated connection of roof to walls

__  Hurricane straps over every rafter/truss (preferable to clips)

__  Roof pitch between 3:12 and 12:12 (< 7:12 preferred)

__  Hip roof design (preferred)

__  Gable roof end walls braced or balloon framed

__  Overhangs < 2 ft. (or engineered, if larger)

__  Roof decking nailed or screwed to rafters (not stapled) at 6 in. o.c.
     or to code (ring shank nails preferred)

__  In tornado zone, 5/8-in. plywood roof decking

__  Roof deck seams sealed (with adhesive roof tape or membrane)

__  Min. #30 roofing felt (consider tear-resistant type) or peel-and-stick
      membrane

__  Wind-rated roofing, properly installed

__  Attic vents protected from wind-driven rain

__  Soffits of rigid material and fastened securely to framing

__  Porch, patio, carport designed and anchored for wind load

__  Columns anchored to foundation and roof beam

Windows and doors:

__  Height < 6’-8”

__  Meet code design pressure ratings (typically > DP 30)

__  Glass protections (plywood panels or certified impact-rated storm
      shutters, panels, screens or window/door units)

__  In tornado zone, passive protection (impact-rated windows)

__  Pressure-rated or reinforced garage door

Fire Protection

__  Fire-resistant wall cladding

__  UL Class A roofing

__  Fire-resistant materials around fireplace and in kitchen

__  Smoke alarm (combination type, battery powered)

__  Lightning rod and grounding system

__  Residential sprinkler system

__  Planned extinguisher mounting locations

Hail and Freeze Hazards

__  Hail-resistant roofing (UL Class 4)

__  All plumbing in heated space or well-insulated

__  Pressure relief exterior faucets

__  Pex piping (flexible)

Termite Resistance

__  No untreated wood left in soil or stored near structure

__  Moisture-managed construction (see Moisture Control section)

__  Professional soil treatment under foundation

__  Termite barriers at hidden pathways

__  Best: no untreated structural wood or vulnerable insulation

__  Borate-treated wall/roof framing, cellulose insulation, foams

__  Pressure-treated (not borate) or composite wood decking

__  Masonry, concrete or steel construction

Slab foundation:

__  Monolithic poured slab

__  Slab specifications to minimize cracking

__  Steel mesh epoxied pipe collars within slab

__  Treatment of control joints and cracks

__  No wood forms, stakes, etc. left in ground

Raised foundations:

__  No hollow concrete blocks below grade

__  Hollow block foundation walls capped with concrete

__  Piers are solid, resistant material

__  Termite shields between foundation and framing to force termite
      exposure

__  Floor joists >18 in. above ground

All foundations:

__  No vulnerable foam insulation under ground (below grade)

__  Min. 8-in. clearance between siding and finished grade

__  Min. 6-in. clearance between wooden steps and soil

__  Foundations detailed for ease of inspection and detection

__  Porches, terraces not filled with soil

__  Porch supports separated from house min. 2 in.

Other:

__  Downspouts, sprinklers, drain lines discharge >2 ft. from house

__  Plantings placed min. 3 feet from foundation

__  No mulch near house or termite-resistant types

__  Plumbing and conduit off the ground, no wood supports

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