Repairs, Remodeling, Additions, and Retrofitting Flood HOME BUILDER S GUIDE TO COASTAL CONSTRUCTION Technical Fact Sheet No. 9.1

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1 Repairs, Remodelig, Additios, ad Retrofittig Flood Techical Fact Sheet No..1 Purpose: To outlie Natioal Flood Isurace Program (NFIP) requiremets for repairs, remodelig, ad additios, ad opportuities for retrofittig i coastal flood hazard areas; to provide recommedatios for exceedig those miimum requiremets. Key Issues Existig buildigs that sustai substatial damage or that are substatially improved (see box o page 3) will be treated as ew costructio ad must meet the commuity s curret floodresistat costructio requiremets (e.g., lowest floor elevatio, foudatio, ad eclosure requiremets). Work o post-flood Isurace Rate Map (FIRM) 1 existig buildigs that are ot substatially damaged or substatially improved (see box o page 3) must meet the commuity s flood-resistat costructio requiremets that were i effect whe the buildig was origially costructed. Work o pre-firm 1 existig buildigs that are ot substatially damaged or substatially improved (see box o page 3) is ot subject to NFIP floodresistat costructio requiremets. With some mior exceptios (e.g., code violatios ad historic buildigs), substatial damage ad substatial improvemet requiremets apply to all buildigs i the flood hazard area, whether or ot a flood isurace policy is i force. Buildigs damaged by a flood ad covered by flood isurace may be eligible for additioal paymets through the Icreased Cost of Compliace (ICC) policy provisios. Check with a isurace aget ad the authority havig jurisdictio (AHJ) for details. Repairs ad remodelig either before or after storm damage provide may opportuities for retrofittig homes ad makig them more resistat to flood damage. Factors That Determie Whether ad How Existig Buildigs Must Comply With NFIP Requiremets Rules goverig the applicability of NFIP ew costructio requiremets to existig buildigs are cofusig to may people; this fact sheet ad Fact Sheet No. 1.2, Summary of Coastal Costructio Requiremets ad Recommedatios for Flood Effects provide guidace o the subject. Whe repairs, remodelig, additios, or improvemets to a existig buildig are udertake, four basic factors determie whether ad how the existig buildig must comply with NFIP requiremets for ew costructio: Value of damage/work whether the cost of repairs to the damaged buildig triggers substatial damage or substatial improvemet regulatios (see page 3). Nature of work whether the work ivolves a expasio of the buildig, either laterally or vertically (a additio), or a eclosure of space below the Base Flood Elevatio (BFE), or the demolitio ad recostructio of a existig buildig, or the relocatio of a existig buildig. Note: Repairs, remodelig, additios, ad retrofittig may also be subject to other commuity ad code requiremets, some of which may be more restrictive tha the NFIP requiremets. Check with the AHJ before udertakig ay work. 1 Pre-FIRM is defied as a buildig for which costructio or substatial improvemet occurred o or before December 31, 174, or before the effective date of the iitial Flood Isurace Rate Map (FIRM) for the commuity. Post-FIRM is defied as a buildig for which costructio or substatial improvemet occurred after December 31, 174, or o or after the effective date of the iitial Flood Isurace Rate Map (FIRM) for the commuity. 2 This fact sheet ad Fact Sheet No. 2 recommed meetig curret NFIP/commuity requiremets i these istaces..1:, REMODELING, ADDITIONS, AND RETROFITTING FLOOD 1 of 7

2 Pre-FIRM or post-firm buildig differet requiremets may apply to pre-firm existig buildigs. Flood zoe differet requiremets may apply i V Zoes ad A Zoes (this icludes both the Coastal A Zoe ad A Zoe). Two other factors may eed to be cosidered (cosult the AHJ regardig whether ad how these factors apply): Code violatios if cited by a code official, the NFIP regulatios exempt certai work to correct existig violatios of state or local health, saitary, or safety code requiremets from the substatial improvemet ad substatial damage calculatios. Historic structures a buildig that is o the Natioal Register of Historic Places or that has bee desigated as historic by federally certified state or local historic preservatio offices (or that is eligible for such desigatio) may be exempt from substatial damage ad substatial improvemet requiremets, provided ay work o the buildig does ot cause the buildig to lose its historic desigatio. A Zoes Subject to Breakig Waves ad Erosio Home Builder s Guide to Coastal Costructio (HBGCC) Recommedatios: Treat buildigs ad lateral additios i A Zoes subject to breakig waves ad erosio like V Zoe buildigs. Elevate all A Zoe lateral additios (except garages) such that the bottom of the lowest horizotal structural member is at, or above, the. For garages (i A Zoes subject to breakig waves ad erosio) below the, costruct with breakaway walls. Code Compliace Defiitios from the Iteratioal Code Coucil Model Buildig Codes ADDITION: A extesio or icrease i floor area or height of a buildig or structure. ALTERATION: Ay costructio or reovatio to a existig structure other tha repair or additio that requires a permit. Also, a chage i a mechaical system that ivolves a extesio, additio or chage to the arragemet, type or purpose of the origial istallatio that requires a permit. REPAIR: The recostructio or reewal of ay part of a existig buildig for the purpose of its maiteace. 200 Iteratioal Residetial Code Requiremets for Additios, Alteratios or Repairs R Additios, alteratios or repairs. Additios, alteratios, or repairs to ay structure shall coform to the requiremets for a ew structure without requirig the existig structure to comply with all of the requiremets of this code, uless otherwise stated. Additios, alteratios or repairs shall ot cause a existig structure to become usafe or adversely affect the performace of the buildig. What Is Substatial Damage? Substatial damage is damage, of ay origi, where the cost to restore the buildig to its predamage coditio equals or exceeds 50 percet of the buildig s market value before the damage occurred. What Is Substatial Improvemet? Substatial improvemet is ay recostructio, rehabilitatio, additio, or improvemet of a buildig, the cost of which equals or exceeds 50 percet of the buildig s pre-improvemet market value. Whe repairs ad improvemets are made simultaeously, all costs are totaled ad compared with the 50 percet of market value threshold. Substatial Damage ad Substatial Improvemet It is ot ucommo for existig coastal buildigs to be modified or expaded over time, ofte i cojuctio with the repair of storm damage. All repairs, remodelig, improvemets, additios, ad retrofittig to buildigs i flood hazard areas must be carried out i coformace with floodplai maagemet ordiaces pertaiig to substatial improvemet ad substatial damage. What Costs Are Icluded i Substatial Damage ad Substatial Improvemet Determiatios? All structural items ad major buildig compoets (e.g., foudatios; beams; trusses; sheathig; walls ad partitios; floors; ceiligs; roof coverig; widows ad doors; brick, stucco, ad sidig; attached decks ad porches). 2 of 7.1:, REMODELING, ADDITIONS, AND RETROFITTING FLOOD

3 Iterior fiish elemets (e.g., tile, viyl floorig, stoe, carpet; plumbig fixtures; gypsum wallboard ad wall fiishes; built-i cabiets, bookcases ad furiture; hardware). Utility ad service equipmet (e.g., HVAC equipmet; plumbig ad wirig; light fixtures ad ceilig fas; security systems; built-i appliaces; water filtratio ad coditioig systems). Market value of all labor ad materials for repairs, demolitio, ad improvemets, icludig maagemet, supervisio, overhead, ad profit (do ot discout voluteer or self-labor or doated/discouted materials). What Costs Are Not Icluded i Substatial Damage ad Substatial Improvemet Determiatios? Desig costs (e.g., plas ad specificatios, surveys ad permits). Clea-up (e.g., debris removal, trasportatio, ad ladfill costs). Cotets (e.g., furiture, rugs, appliaces ot built i). Outside improvemets (e.g., ladscapig, irrigatio systems, sidewalks ad patios, feces, lightig, swimmig pools ad hot tubs, sheds, gazebos, detached garages). Note: Some jurisdictios have eacted more restrictive requiremets some use a less-tha- 50-percet damage/improvemet threshold. Some track the cumulative value of damage ad improvemets over time. Cosult the AHJ for local requiremets. Additios Additios icrease the square footage or exteral dimesios of a buildig. They ca be divided ito lateral additios, vertical additios, ad eclosures of areas below existig buildigs. Whe cosiderig additios, it is importat to cosider that chages to the shape of the buildig may impact the potetial damages to the house. A lateral additio may chage the way flood waters travel aroud the structure ad potetially create obstructios for flood-bore debris that may require additioal foudatio modificatios. Vertical additios may also impose greater loads o the existig structure. A qualified desig professioal should evaluate the loadig to the etire structure to see if additioal structural modificatios are required i order to maitai the structure s ability to sustai flood loadig. Lateral Additios If a lateral additio costitutes a substatial improvemet to a V Zoe buildig, both the additio ad the existig buildig must comply with the effective base flood elevatio, foudatio, ad other flood requiremets for ew V Zoe costructio (see Figure 1). Existig Buildig i V Zoe Compliat Reovated/Remodeled Buildig Existig pre-firm buildig below Figure 1. Substatial improvemet: Reovated/remodeled buildig i a V Zoe..1:, REMODELING, ADDITIONS, AND RETROFITTING FLOOD 3 of 7

4 If a lateral additio costitutes a substatial improvemet to a A Zoe buildig, oly the additio must comply with the curret floor elevatio, foudatio, ad other flood requiremets for ew costructio, as log as the alteratios to the existig buildig are the miimum ecessary. 3 Miimum alteratios ecessary meas the existig buildig is ot altered, except for cuttig a etrace through the existig buildig wall ito the additio, ad except for the miimum alteratios ecessary to tie the additio to the buildig. If more extesive alteratios are made to the existig buildig, it too must be brought ito compliace with the requiremets for ew costructio. If a lateral additio to a pre-firm buildig does ot costitute a substatial improvemet, either the additio or the existig buildig must be elevated. However, the HBGCC recommeds that both the existig buildig ad the additio be elevated to, or above, the curret, i a maer cosistet with curret NFIP requiremets for ew costructio, ad usig a V Zoe-type foudatio i V Zoes ad i Coastal A Zoes. If a lateral additio to a post-firm buildig does ot costitute a substatial improvemet, the additio must be elevated i accordace with the flood requiremets i effect at the time the buildig was origially costructed, eve if the BFE ad flood hazard have chaged over time. The HBGCC recommeds that both the existig buildig ad the additio be elevated to, or above, the curret, i a maer cosistet with curret NFIP requiremets for ew costructio, ad usig a V Zoe-type foudatio i V Zoes ad i Coastal A Zoes (see Figure 2). Existig Buildig Compliat Lateral Additio Existig buildig A attached garage does ot have to be elevated above, but must be costructed with breakaway walls. Lateral additio Pile/colum foudatio Existig, NFIP-compliat post-firm buildig with bottom of lowest horizotal structural member at or above old (i effect at time of origial costructio) Bottom of lowest horizotal structural member at or above ew Requiremet: Both existig buildig ad additio must be elevated o ope (pile/colum) foudatio with bottom of lowest horizotal structural member at or above ew (i effect at time of costructio of lateral additio) Figure 2. Substatial improvemet: Lateral additio to a pre-firm buildig i a V Zoe. 3 However, the HBGCC recommeds that both the existig buildig ad the additio be elevated to, or above, the curret, i a maer cosistet with curret NFIP requiremets, ad usig a V Zoe-type foudatio i Coastal A Zoes. 4 of 7.1:, REMODELING, ADDITIONS, AND RETROFITTING FLOOD

5 Vertical Additios If a vertical additio to a V Zoe or A Zoe buildig costitutes a substatial improvemet, both the additio ad the existig buildig must comply with the effective base flood elevatio, foudatio, ad other flood requiremets for ew costructio (see Figure 3). If a vertical additio to a pre-firm V Zoe or A Zoe buildig does ot costitute a substatial improvemet, either the additio or the existig buildig must be elevated or otherwise brought ito compliace with NFIP requiremets. However, the HBGCC recommeds that both the additio ad the existig buildig be elevated to, or above, the curret i a maer cosistet with curret NFIP requiremets for ew costructio, ad usig a V Zoe-type foudatio i V Zoes ad i Coastal A Zoes (see Figure 3). The HBGCC also recommeds strogly agaist usig ay space below the curret BFE for habitable uses (uses permitted by the NFIP are parkig, storage, ad buildig access). If a vertical additio to a post-firm V Zoe or A Zoe buildig does ot costitute a substatial improvemet, the additio must be desiged ad costructed i accordace with the flood requiremets i effect at the time the buildig was origially costructed. However, BFEs ad flood zoes chage over time as areas are remapped. The HBGCC recommeds that both the additio ad the existig buildig be elevated to, or above, the curret i a maer cosistet with curret NFIP requiremets for ew costructio, ad usig a V Zoe-type foudatio i V Zoes ad i Coastal A Zoes. The HBGCC also recommeds strogly agaist usig ay space below the curret BFE for habitable uses (uses permitted by the NFIP are parkig, storage, ad buildig access). Compliat Vertical Additio Existig Buildig New, exteded pile/colum foudatio Bottom of lowest horizotal structural member at or above Existig, Pre-FIRM buildigbelow Bottom of lowest horizotal structural member at or above Requiremet: Both existig buildig ad additio must be elevated to or above Figure 3. Substatial improvemet: Vertical additio to a pre-firm buildig i a V Zoe..1:, REMODELING, ADDITIONS, AND RETROFITTING FLOOD 5 of 7

6 Eclosures of Areas Below Existig Buildigs Eclosures below existig buildigs are treated like vertical additios. Existig NFIP requiremets: (1) do ot eclose ad covert to habitable use ay space below the BFE uder ay circumstaces, ad (2) costruct oly breakaway eclosures below existig buildigs i V Zoes ad i Coastal A Zoes. HBGCC recommedatio: i V Zoes ad Coastal A Zoes the area below the BFE should be built free of obstructio. Use ope lattice, screeig, or breakaway walls. For requiremets cocerig eclosures below elevated buildigs see Fact Sheet 8.1. It should be oted that eclosures built with breakaway walls below the BFE may result i icreased isurace premiums whe compared to a ope foudatio. Recostructio of a Destroyed or Razed Buildig I all cases (pre-firm or post-firm, V Zoe or A Zoe) where a etire buildig is destroyed or purposefully demolished or razed, the replacemet buildig is cosidered ew costructio ad the replacemet buildig must meet the curret NFIP requiremets, eve if it is built o the foudatio of the origial buildig. Movig a Existig Buildig Whe a existig buildig (pre-firm or post-firm, V Zoe or A Zoe) is moved to a ew locatio or site, the work is cosidered ew costructio ad if the relocated buildig is i the SFHA, it must be istalled so as to comply with NFIP requiremets. Materials Whe costructig i coastal eviromets, carefully cosider what costructio materials to select. The NFIP Techical Bulleti 2, Flood Damage-Resistat Materials Requiremets (August 2008), provides valuable iformatio regardig the applicability of various costructio materials i a coastal eviromet. For additioal iformatio, see Fact Sheet 1.7, Coastal Buildig Materials. Followig a storm evet, repairs should ot be started util the problem is properly evaluated ad materials are selected that will etirely remedy the damage. All costs of repairs should be idetified ad quatified prior to startig repairs. Repairs Correctio of oly the apparet surface damage ca lead to uaddressed or overlooked problems beeath the surface that ca potetially cause major issues with the structural stability of the buildig. Proper ispectios of damage ofte ot oly require demolitio or removal of the physically damaged buildig compoet, but also removal of associated exterior claddig. Wid-drive rai for example ca lead to compromised coectios ad the decayig or rottig of buildig materials that may ot be visible without further ivestigatio. Isurace Cosequeces Desigers ad owers should kow that the work described previously may have isurace cosequeces, especially if ot completed strictly i accordace with NFIP requiremets. I geeral, most chages to a existig buildig that result from less-tha-substatial damage, or that do ot costitute substatial improvemet, will ot chage the status from pre-firm to post-firm. However, it is required that substatially improved or substatially damaged buildigs be brought ito compliace. NFIP flood isurace policies o those buildigs are writte usig rates based o elevatio. I most cases, the premium will decrease whe a pre- FIRM buildig is substatially improved ad brought ito compliace. The buildig becomes a post-firm buildig ad premiums are calculated usig elevatio rates. Failure to comply with the substatial damage or substatial improvemet requiremets will result i a buildig s status beig chaged ad i higher flood isurace premiums. For example: If a NFIP-compliat eclosure built with breakaway walls is added below a post-firm V Zoe buildig, the buildig will o loger be rated as free of obstructios. Flood isurace premiums o these buildigs will be higher. If the eclosure is ot compliat with all NFIP requiremets, higher premiums will result. If work o a existig V Zoe buildig costitutes a substatial improvemet, the buildig will be rated o a curret actuarial basis. Ay pre-firm desigatio will be lost ad curret post-firm rates will be used. If a NFIP-compliat lateral additio costitutig a substatial improvemet is made to a pre- FIRM A Zoe buildig ad o chages were made to the existig buildig, the buildig will retai its pre-firm desigatio ad ratig. However, if the additio does ot comply with all requiremets, or if more tha the miimum alteratio ecessary was made to the existig buildig, the buildig ad additio s lowest floor must be elevated to or above the BFE. The buildig icludig the additio will be rated with post-firm actuarial rates. Retrofit ad Remodelig Opportuities Retrofit opportuities will likely preset themselves ay time repair or maiteace work is udertake for a major elemet of a buildig. Improvemets to the buildig that are made to icrease resistace to 6 of 7.1:, REMODELING, ADDITIONS, AND RETROFITTING FLOOD

7 the effects of atural hazards should focus o those items that will potetially retur the largest beefit to the buildig ower. Some examples of retrofit opportuities may iclude: Improvig floor-framig-to-beam coectios wheever they are accessible (see Fact Sheet 4.1, Load Paths ad Fact Sheet 4.3, Use of Coectors ad Brackets for additioal iformatio). Improvig beam-to-pile coectios wheever they are accessible (see Fact Sheet 3.3, Wood-Pile-to-Beam Coectios for additioal iformatio). Periodically checkig ad ispectig flood opeigs to make sure that they are ot blocked ad fuctioig properly. If the house is older, check to make sure that flood opeigs are sized correctly. Cosult NFIP Techical Bulleti 1, Opeigs I Foudatio Walls ad Walls of Eclosures (August 2008) for proper flood opeig guidace. Also see Fact Sheet 3.5, Foudatio Walls for additioal iformatio. At ay time deficiet metal coectors are foud, they should be replaced with stailess steel coectors or metal coectors with proper corrosio protectio, such as hot-dip galvaized steel (see Fact Sheet 1.7, Coastal Buildig Materials for additioal iformatio). Whe HVAC equipmet is replaced, the replacemet equipmet selected should icorporate a more corrosio-resistat desig so that it will last loger i a coastal eviromet ad should be elevated to, or above, the. The equipmet should be adequately achored to resist wid ad seismic loads (see Fact Sheet 8.3, Protectig Utilities for additioal iformatio). Improvig utility attachmets whe the outside equipmet is replaced or relocated (see Fact Sheet 8.3, Protectig Utilities for additioal iformatio). To miimize the effects of corrosio, carbo steel hadrails ca be replaced at ay time with viylcoated, plastic, stailess steel, or wood hadrails. Wood hadrails may require frequet treatmet or paitig ad appropriate fasteers must be used (see Fact Sheet 1.7, Coastal Buildig Materials for additioal iformatio). Carbo steel hadrails may also be paited with a zicrich, viyl, or epoxy pait appropriate for exposed wet ad salt-spray eviromets. Regardless of the product used, proper maiteace is always ecessary i order to esure a safe hadrail. Cosider sewer backflow preveter valves if they are ot curretly part of the buildig s plumbig. The istallatio should be doe by a licesed plumber. If the curret water heater is at, or below, the, cosider switchig to a takless water heater. A takless water heater will take up less space ad ca be mouted to a wall due to its small size. I additio to allowig the user to mout it higher tha a traditioal water heater, it may also result i reduced eergy costs. Older structures should cosider elevatio as a possible retrofit or mitigatio opportuity. Older pre-firm structures ca be at sigificat risk to floodig evets. I coastal eviromets, eve a little additioal elevatio ca result i improved flood resistace. Costs ca vary greatly depedig o the type of foudatio. It is importat whe cosiderig a elevatio project to cosult a desig professioal before cosiderig how much elevatio ad the appropriate foudatio type. A cotractor experieced with the elevatio of buildigs should be used for the actual liftig of the house. It is commo for the house to require other structural work to the iterior ad exterior followig the elevatio. Before udertakig a elevatio, cosider the elevatio process, which usually results i the structure beig set o top of a foudatio that is more level tha the origial foudatio. This process ca result i cosmetic crackig as the structure s foudatio settles agai ad may require additioal work to get the structure s aesthetics back to a pre-elevatio appearace. Additioal Resources FEMA Substatial Improvemet/Substatial Damage Desk Referece. FEMA P fema.gov/library/viewrecord.do?id=4160 FEMA Coastal Costructio Maual, Chapter 14. FEMA 55. ( Florida Departmet of Commuity Affairs A Local Official s Guide to Implemetig the Natioal Flood Isurace Program i Florida. (See Chapter 6). ( NFIPStudyCourse/Appedix%20E%20-%20FL%20 Hadbook.pdf) Developed i associatio with the Natioal Associatio of Home Builders Research Ceter.1:, REMODELING, ADDITIONS, AND RETROFITTING FLOOD 7 of 7

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