RESIDENTIAL AND OTHER LOW-RISE BUILDINGS …

1 FPA-SC-07 Presentation 19 Feb 03 FOUNDATION maintenance AND inspection GUIDEFORRESIDENTIAL AND OTHER LOW-RISE BUILDINGS Document no:FPA-SC-07-0 Developed by:FPA Structural Committee Committee chairs: Main Committee - Ron Kelm, - James Austin, Presented by:James Austin, , Member Presented to :The FPA at Presented on:February 19, 2003 FPA-SC-07 Presentation 19 Feb 03 PRESENTATION OUTLINE1. Why was it written?2. Who needs it?3. What are the benefits?4. How is it organized?5. How is it to be used?FPA-SC-07 Presentation 19 Feb 031. WHY WAS IT WRITTEN? Too Many Foundation Problems Too Much Money Spent on Foundation Repairs and LitigationFPA-SC-07 Presentation 19 Feb 03 Slab crack found below carpetFPA-SC-07 Presentation 19 Feb 03 The soil is a sleeping monsterFPA-SC-07 Presentation 19 Feb 03 Water can awaken the monsterFPA-SC-07 Presentation 19 Feb 032. WHO NEEDS IT?

2 Homeowners LOW-RISE Building Owners Tenants Builders Warranty Companies Architects & EngineersFPA-SC-07 Presentation 19 Feb 033. WHAT ARE THE BENEFITS? Minimizes Foundation Movement Minimizes Foundation Repairs No Repairs = Higher Resale Price Ultimately Reduces Foundation Design and Construction CostsFPA-SC-07 Presentation 19 Feb 034. HOW IS IT TO BE USED? Print & Use Checklists Take Photos & Record Distress Refer to Design Considerations Get Help if Movement is Suspected:FPA-SC-07 Presentation 19 Feb 03 Stucco crack above windowFPA-SC-07 Presentation 19 Feb 03 Garage header separationFPA-SC-07 Presentation 19 Feb 03 Outside siding separationFPA-SC-07 Presentation 19 Feb 035. HOW IS IT ORGANIZED? Preface Definitions Survey & maintenance Discussion Foundation Design Considerations Survey & maintenance ChecklistsFPA-SC-07 Presentation 19 Feb 03 Shower tile / drywall crackFPA-SC-07 Presentation 19 Feb 03 Ceiling trim separationFPA-SC-07 Presentation 19 Feb 03 Corner door trim separationFPA-SC-07 Presentation 19 Feb 03 FOUNDATION maintenance AND inspection GUIDEFORRESIDENTIAL AND OTHER LOW-RISE BUILDINGSbyThe Structural CommitteeofThe Foundation Performance , TexasDocument # FPA-SC-07-0 ISSUE HISTORYRev#Date DescriptionSubcommitteeChair(s)

3 SubcommitteeMembersA20 Jul 01 For Committee CommentsB1 Oct 01 For Committee CommentsC5 May 02 For Committee CommentsD6 Aug 02 Issued for FPA Peer ReviewE3 Jan 03 For Committee CommentsF6 Jan 03 For Committee Final Comments08 Feb 03 Issued for Website PublishingJames AustinJohn ClarkRon KelmBill PolhemusTaylor SealyMichael SkollerJack SpiveyGeorge WoznyFPA-SC-07 Presentation 19 Feb 03 PREFACEThis document has been developed by a group of foundation design engineers in Southeast Texaswith the goal to educate homeowners, LOW-RISE building owners, and tenants of their duties tomaintain their foundations . foundations , like OTHER parts of a home or building, require a certainamount of maintenance to avoid premature need for this document has been prompted by a large number of RESIDENTIAL and low-risebuilding foundation problems in Southeast Texas, some of which might have been avoided hadowners and tenants properly understood the foundation engineer's design basis and provided therequired foundation maintenance .

4 As a result, this document has been prepared and made freelyavailable to the public through the Foundation Performance Association so that owners, tenants, realtors, builders, inspectors, engineers,architects, repair contractors, and others involved with RESIDENTIAL and OTHER LOW-RISE buildingfoundations may benefit from the information it properly engineered foundation will be designed to support its superstructure and buffer it fromground movements and OTHER loadings so that the structural and architectural components do notshow significant distress. As with any engineering design, there will be design assumptions madewhich limit the scope of design so that a foundation can be constructed which is not only strong,meeting the requirements of the Building Code and accepted standard engineering practice, but isalso foundation design engineers will want building owners to be satisfied with the performance ofthe foundations for their BUILDINGS .

5 However, building owners must be practical about the natureof the area in which they have built. They must expect and accept a certain amount of foundationmovement. With proper maintenance , this movement can be minimized. This document detailsthe responsibilities that foundation design engineers need and expect from the owners and following the recommendations contained within this document, the maintainer can greatlyincrease the probability that the foundation will perform as originally document was written specifically for use in the southeast region of the state of Texas andprimarily within the City of Houston and the surrounding metropolitan area. Therefore, it shouldbe used with caution if used elsewhere, or if adapted for foundations OTHER than those supportingresidential or LOW-RISE structures. The Foundation Performance Association and its members makeno warranty regarding the information contained herein and will not be liable for any damages,including consequential damages, resulting from the use of this Presentation 19 Feb 03 DEFINITIONSFor the purposes of this guide , certain terms are defined as follows:Foundation is defined as a composite of soil, concrete, steel, wood, plastic, and OTHER materialsthat are designed to work together to provide a stable base that supports a is defined as the building components above the foundation such as the structuralframing and the architectural coverings for the floor, walls, ceilings, and Design Engineer is defined as a licensed professional engineer that designsfoundations (also called Engineer of Record).

6 Maintainer is defined as the person or group responsible for monitoring and maintaining thecondition of the foundation, usually the owner or is defined as soil particles that are at least millimeters but less than millimeters indiameter. (Note: 1 millimeter = inch)Silt is defined as soil particles that are at least millimeters (2 microns) but less than in is defined as microscopic soil particles measuring less than millimeters (2 microns) is defined as a property of soil, indicating the soil particles have little potential toswell when moisture is absorbed by them and little potential to shrink when moisture is extractedfrom is defined as a property of soil, usually clay, indicating the soil particles have apotential to swell when moisture is absorbed by them and to shrink when moisture is extractedfrom them. The shrink-swell movements can be in all six directions but the directions of mostconcern in this guide are the vertical upward (heave) and the vertical downward (subsidence)movements, as defined is defined as downward movement of underlying supporting soils, taking with it thefoundation and superstructure, and is due to vertical loads from above which are in excess of theultimate bearing capacity of the particular soil stratum.

7 Settlement may occur in all types of is defined as downward movement of underlying supporting expansive soils, takingwith it the foundation and superstructure, and is due to the extraction of moisture from theexpansive soil particles, and consequently, shrinkage of the expansive soil is defined as upward movement of underlying supporting expansive soils, taking with it thefoundation and superstructure, and is due to the addition of moisture to the expansive soilparticles, and consequently, swelling of the expansive soil Presentation 19 Feb 03 TTTTAAAABBBBLLLLEEEE OOOOFFFF INITIAL SURVEY Exterior Interior maintenance Exterior Interior DESIGN Foundation Superstructure Architectural Soil Soil Site Site Initial Soil MovementAAAAPPPPPPPPEEEENNNNDDDDIIIICCCC EEEESSSS((((CCCCHHHHEEEECCCCKKKKLLLLIIII SSSSTTTTSSSS))))AINITIAL EXTERIOR SURVEYBINITIAL INTERIOR SURVEYCREGULAR EXTERIOR MAINTENANCEDREGULAR INTERIOR MAINTENANCEFPA-SC-07 Presentation 19 Feb INTRODUCTIONThis foundation maintenance guide is divided into several parts, summarized as follows.

8 InSection 2, initial survey requirements are discussed. These initial survey requirements are targetedfor use by the maintainer. The intent is that they will be implemented upon initial occupation,whether the structure is new or used. In Section 3, the regular maintenance requirements aresummarized, and the requirements for maintenance of the foundation are detailed. In Section 4, afoundation design philosophy is presented, giving the user an understanding of typicalassumptions made by the foundation design engineer to design a foundation. Finally, theappendices contain checklists for maintainers to print and use in surveying and maintaining INITIAL SURVEY GeneralSoon after the initial purchase of the structure is complete, the maintainer may use the checklistsin Appendices A and B to determine what action may be required to help ensure that the originalfoundation design philosophy will not be compromised.

9 The items in the checklists apply whetherthe purchase is for a new or a used there are any signs of distress, the maintainer should employ an experienced consultant, such asa licensed structural inspector to determine if the distress is indicative of a foundation movementproblem. It the structure is newly built, the original builder and or foundation design engineer ofrecord should be contacted since they will already be familiar with the structure and usually havesome responsibility to ensure its the distress is found to be the result of foundation movement, the inspector/builder/engineer ofrecord may recommend that a forensic engineer or OTHER forensic consultant then be hired toinvestigate the cause of movement. The inspector/builder/engineer of record should also provide alevel distortion survey of the foundation. Even if they do not find a cause for concern, the leveldistortion survey and OTHER documentation provided will be a valuable baseline for a forensicengineer or OTHER consultant to use in case there is foundation movement in the there are signs of distress for which the maintainer is unsure if they are attributable tofoundation movement, it may be helpful to refer to the Foundation Performance Association stechnical paper # FPA-SC-03, Distress Phenomena often Mistaken for Foundation Movement,freely available to the public at foundations on expansive soils have maintenance requirements that differ from or areadditional to those for foundations on non-expansive soils, the maintainer should determine if thebuilding is located in an area where expansive soils exist or are likely to exist.

10 One sure way tomake this determination is to engage a geotechnical engineer to sample and test the soils at thebuilding site, but this method may cost more than the maintainer is willing to spend. A lessexpensive but less accurate method is to obtain the soil survey booklet from the Departmentof Agriculture for the county where the building is located. Alternately, the maintainer maycontact the applicable City or County engineering office and question the building inspectorsabout their knowledge of expansive soils in the Presentation 19 Feb Exterior SurveySoon after the initial purchase of the structure is complete, the maintainer should make areconnaissance-type survey of the site and exterior of the structure for evidence of problemsaffecting the foundation design. Photographs or OTHER documentation should be made of anyobvious or suspected distress or OTHER anomalies observed. For later comparison purposes, it isalso recommended to take photographs of all exterior perimeter walls to document their initialcondition.