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FOUNDATION AND FRAMING IMPROVEMENT MANUAL-9-2018

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Published by Lineberger Consulting Engineers, Inc., 2018-09-28 18:08:10

FOUNDATION IMPROVEMENT MANUAL

FOUNDATION AND FRAMING IMPROVEMENT MANUAL-9-2018

FOUNDATION
IMPROVEMENT

MANUAL

NOTE: THIS DOCUMENT PROVIDES SUPPORTING REFERENCE INFORMATION FOR THE ENGINEERING REPORT AND
DOES NOT CONSTITUTE AN ENGINEERING OPINION, AND AS SUCH:

1. may be used/implemented at the sole discretion of the customer or customer's representative;
2. does not constitute engineering opinions or recommendations, and
3. shall not be construed as an engineering design instrument.

Page 1 of 6……………………………..Form TXASCE-A-Rev. V9-2018………………..Copyright © 2001-2018 Lineberger Consulting Engineers, Inc……All Rights Reserved.

FOUNDATION IMPROVEMENT MANUAL-15-

STEPS TO IMPROVING FOUNDATION PERFORMANCE

STEP ACTION GUIDELINE

ONE Improve 1. Eliminate any rogue-16- sources of water near or below the foundation system which may
Foundation potentially diminish its acceptable performance. (Plumbing leak tests are advised).
TWO Performance
2. Potentially limit or minimize undesirable and/or unacceptable residence material distress
Observe the resulting from an underperforming foundation system(s) by implementing guidelines as
impact, if any, of described in section 1, 2, and 3 of this document.
implementing Step
ONE (above); 3. Apply a low/medium viscosity epoxy adhesive material into any horizontal/vertical concrete
surface floor/perimeter beam wall cracks exceeding 1/16” width to their full depth to prevent
crack growth (refer to section 1 of this document).

1. After initially implementing Step ONE (above), customer may observe and confirm the
foundation's/residence response to Step ONE over a customer specified period of time
(generally a minimum of 12-24 months) to determine if:
i. existing residence brittle material distress increases in its severity, or
ii. existing residence brittle material distress does not change or improves/diminishes in its
severity (i. e. cracks close or doors open/close without binding, etc.), or
iii. new residence brittle material develops.

2. Should existing residence brittle material distress increase in its severity or if new residence
brittle material develops, the customer may consider forensically-17- investigating the
foundation system to:
i. assess its structural pathology,
ii. determine the origin and cause of any structural foundation failure, and
iii. determine the appropriate method to structurally stabilize the foundation system if
needed.

Page 2 of 6……………………………..Form TXASCE-A-Rev. V9-2018………………..Copyright © 2001-2018 Lineberger Consulting Engineers, Inc……All Rights Reserved.

FOUNDATION IMPROVEMENT MANUAL

1 CONCRETE AND MASONRY REPAIR AND WATERPROOFING GUIDELINES

1.A CONCRETE AND MASONRY CRACK REPAIR

1. Assure ground/concrete/masonry surface slopes allow code compliant draining/conveyance of stormwater runoff away from the
residence/building foundation perimeter beam face (refer to section 3 of this document).

2. Concrete surface crack or discontinuity remedial guideline: Generally, the customer may apply a low/medium viscosity epoxy
adhesive to concrete floor/perimeter wall surface cracks to help prevent their growth (length, width, depth) over time, and to restore
the structural integrity of discrete concrete areas. Refer to: https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias
%3Daps&field-keywords=Crack-Pac%C2%AE+Kit+%28ETIPAC10KT%29 for purchasing information pertaining to a discrete
concrete crack repair kit. Please note:
(a) Prior to repairing any concrete cracking, the customer should assure concrete surfaces near “suspect areas” (concrete surface
cracks or discontinuous surface areas such as cold joints, bulges, or depressions) retain their integrity by “sound testing” the
concrete surface layer as follows:
i. using a hard rubber or steel hammer, lightly strike the concrete surface suspect areas with the hammerhead;
ii. if the hammer strikes do produce a “hollow” sounding area within a suspect area and below the concrete surface, remove
concrete surface layer above the hollow sounding area using a chipping hammer or similar method;
iii. fill the void within the “hollow area” as specified by the manufacturer using an approved ASTM C387 yield, high strength
mixture of structural lightweight aggregate and cement concrete based filler material such as Sakrete MAXIMIZER®
Concrete;
iv. Apply a finish concrete (sand & cement) parge coat if desired;
(b) For suspect concrete crack areas which do not produce hollow soundings:
i. Clean the crack area to its full depth (if possible) using an air or wire brush to prepare it for receiving the epoxy adhesive;
ii. Apply the epoxy adhesive (by gravity pour or pressure injection) to the full depth “native” crack surfaces;
iii. Do not saw cut or “V-groove” the crack. Doing so impacts concrete cuttings into the crack and its secondary
fracture/fissures and diminishes available crack bonding surface area. Diminished bonding surfaces reduce the
effectiveness (tensile strength) of the epoxy crack repair;
(c) Prevent excessive epoxy leakage and loss through the crack bottom by using a medium viscosity epoxy initially to fill and seal
the bottom of the crack. Finish filling the crack with a low viscosity epoxy;

1.B WATERPROOFING

1. Consider waterproofing:
(a) any exposed foundation metallic materials (water repellent epoxy based construction adhesive may be used), and
(b) any gap(s) between concrete flatwork (drives & porches) & the adjacent house foundation perimeter beam (water repellent
Polyurethane Elastomeric Sealant may be used.)
(c) any masonry veneer joints, cracks, or voids (temporary waterproofing measures may include filling cracks/voids with a water
repellent silicone or similar material).

2. Masonry Veneer Wall Covering Performance Enhancements:
(a) Add expansion joints along wall perimeters at approved intervals to help limit lateral and vertical wall covering displacement;
(b) Assure wood frame structural systems supporting masonry veneer wall coverings are proportioned to help limit lateral and
vertical wall displacement;

3. Assure any masonry veneer wall covering materials are securely anchored to their supporting wood frame structural systems;

Page 3 of 6……………………………..Form TXASCE-A-Rev. V9-2018………………..Copyright © 2001-2018 Lineberger Consulting Engineers, Inc……All Rights Reserved.

FOUNDATION IMPROVEMENT MANUAL

2 FOUNDATION BEARING MATERIAL MOISTURE MANAGEMENT

Shallow bearing foundation systems require uniform bearing material (soil or engineered fill materials) moisture contents to achieve

reasonably optimal performance. The following moisture management techniques (a.k.a. Foundation Drainage) may be considered by the

customer to help achieve and maintain uniform bearing material moisture contents:

1. Maintain a uniform soil moisture content along and about the foundation system perimeter where it is reasonable to do so.

Guidelines (a) and (b) below may be followed:

(a) Excessively wet foundation bearing soils can swell volumetrically causing ground supported foundation systems to displace

vertically (“heave” or “settle”) upward or downward over time. Assure bearing depth soils near the foundation perimeter do

not become excessively saturated. To the extent allowable, assure uniform bearing depth soil moisture content conditions

along the foundation perimeter areas.

(b) Excessively dry foundation bearing soils can shrink volumetrically causing ground supported foundation systems to displace

vertically (“settle”) downward over time. Assure bearing depth soils near the foundation perimeter do not become excessively

desiccated. To the extent allowable, assure uniform bearing depth soil moisture content conditions along the foundation

perimeter areas.

2. If plumbing (irrigation, sprinkler, fire, water softener, swimming pool, sub-foundation water supply or drain system) leaks are

suspected, or if previous plumbing tests did not comprehensively test all residence drain or water supply lines, statically test them to

assure their water tightness. Localized water accumulations beneath a shallow bearing ground supported foundation system can

cause a localized and potentially damaging upward/downward displacement of the foundation system.

3. Consider redirecting: new and/or existing rain-gutter downspout systems away from the foundation perimeter, or

4. Consider connecting: new and/or existing rain-gutter downspout systems to an existing and/or a

proposed underground drain system (refer to “Surface Water Drainage, Option A) to facilitate the capture, collection, and draining

(to an approved outfall location) of roof stormwater away from the foundation perimeter to:

(a) help prevent ground surface erosion or scouring;

(b) help prevent foundation bearing soil oversaturation;

(c) help prevent localized water ponding in areas on or about the foundation perimeter.

5. Landscape watering should be done in a uniform, systematic manner as equally as possible on all sides of the foundation to keep the

soil moist. Areas of the soil that do not have ground cover may require more moisture as they are more susceptible to evaporation.

During extreme hot & dry periods, close observations should be made around foundations to insure that adequate watering is being

provided to keep soil from separating or pulling back from the foundation.

6. Assure any air conditioning condensate discharge lines direct condensate away from the foundation system perimeter to prevent

localized foundation bearing soil saturation.

7. Assure any water heater TPRV discharge lines direct their liquid effluent away from the foundation system perimeter to prevent

localized foundation bearing soil saturation.

8. Attempting to replace expected local climate precipitation by artificially imbibing moisture into the foundation bearing soils with

appliances (example: soaker hose or irrigation system) may negatively impact the structural efficacy the foundation system. No

known authoritative treatise or code based protocols exist which provide approved instructions for their safe, hazard free, long term

use.

Page 4 of 6……………………………..Form TXASCE-A-Rev. V9-2018………………..Copyright © 2001-2018 Lineberger Consulting Engineers, Inc……All Rights Reserved.

FOUNDATION IMPROVEMENT MANUAL

3 FOUNDATION DRAINAGE IMPROVEMENT GUIDELINES

Residential ground surface storm drain systems must transport excess moisture away from designated areas where excess water would
otherwise prevent the normal use of a residential property. If stormwater runoff collects and saturates the foundation bearing soils, the
structure can displace abnormally, resulting in structural foundation distress. Finished ground surfaces must be sloped to freely drain away
from the house perimeter according to the International Residential Code §R401.3-19-. Perpetually moist ground surfaces can limit the
appropriate use of residential yard areas and may present a health hazard. Stormwater must exit the property to assure unrestricted, healthy,
and environmentally safe use of land areas within residential property boundaries.

Section 7.3 of the “ASCE (American Society of Civil Engineers) Guidelines for the Evaluation and Repair of Residential Foundations”
provides the following non-structural guidelines and criteria for improving or modifying residential storm water drainage systems.

• Improve or Modify Existing Ground Surface System (ASCE, section 7.35):
i. Surface Grading along the Foundation perimeter. A minimum slope of 5% (6” fall per 10’) away from the foundation perimeter
should be provided for adjacent ground areas;
ii. Ground surface swales parallel to the house walls shall have longitudinal slopes of at least 2% (6” per 25') if practical, and 1%
(3” per 25’) minimum;
iii. Eroded surfaces should be replaced with vegetated surfaces;
iv. Gaps between concrete surfaces along the foundation system perimeter allowing surface water to infiltrate into the foundation
bearing soils should be eliminated;
v. Concrete surfaces allowing water to flow towards the foundation system perimeter should be modified to direct water away
from the foundation perimeter (atrium gravity drain or mechanical sump pump drain system);
vi. Erosion Control. Ground cover should be placed in areas where ground surface erosion currently exists.

Other improvements may also be appropriate. The customer, at customer's option, may consider implementing the following optional
drainage techniques which can be used to limit long term slab-on-grade foundation performance degradation (3.A and 3.B):

3.A SUBSURFACE STORMWATER DRAINAGE [Option A-Solid Pipe]

Solid Plastic/PVC Pipe System: Gravity stormwater drain systems help prevent foundation bearing soil saturation by collecting, capturing
and conveying excess stormwater runoff to approved outfall locations. The ground surface should be graded to slope to one or more operable
subsurface solid drainpipe (plastic or PVC) single collector inlets or continuous grate type rectangular inlets. The drain inlets should be
located to drain excess water from the side and rear yards and discharge to the approved subdivision stormwater conveyance system.
Stormwater earthen or concrete drain channels or curbed streets often serve as drain outfalls. (Note: If discharging to the street is not
feasible, the customer may consider discharging the stormwater within the yard provided such discharge permeates into the soil and does not
result in ground surface flooding or water ponding in any area, including any adjoining property, easement, or right of way.) Subsurface
drain system cleanouts should be provided at 50 feet intervals for proper maintenance. Roof rainfall gutter downspouts may be connected to
the subsurface solid pipe system provided the pipe has sufficient capacity to prevent a backwater condition. The pipe should have a
minimum slope of 1% to the daylight discharge. In any case, the ground surface slope along the foundation perimeter must comply with
local building code requirements.

3.B SUBSURFACE STORMWATER DRAINAGE [Option B-Perforated Pipe]

Perforated Plastic/PVC Pipe System: Gravity stormwater drain systems help prevent foundation bearing soil saturation by collecting,
capturing and conveying excess stormwater runoff to approved outfall locations. As an additional measure to drain the building yard areas,
subsurface perforated pipes placed in an aggregate filled trench (“French Drain”) along with an optional filter fabric to prevent pipe
stoppages may be optionally considered. The pipe should have a minimum slope of 1% to the surface outfall. Cleanouts should be provided
at 50 feet intervals for maintenance. In any case, the ground surface slope along the foundation perimeter must comply with local code
requirements. Gutter downspouts should not be connected to a perforated pipe system.

----END OF FOUNDATION IMPROVEMENT MANUAL---

Page 5 of 6……………………………..Form TXASCE-A-Rev. V9-2018………………..Copyright © 2001-2018 Lineberger Consulting Engineers, Inc……All Rights Reserved.

MANUAL NOTES

-15- Customer awareness/expectations: (Realistic foundation performance expectations based upon this investigation
analysis & findings): While not desirable nor acceptable, it would not be unreasonable to expect additional brittle mate-
rial cracking to occur over time. Any floor surface or foundation perimeter beam face cracks > 1/16” width should be
filled with a low-to-medium viscosity epoxy resin to their full depth within 6-12 months from their date of discovery. Note:
Previous improper (defective) foundation system structural modifications may increase the probability/risk of dimin-
ished foundation structural performance. Structurally modified foundation systems which have no traceable underly-
ing design premise (“hybrid structural modifications”) may have a relatively higher risk of poor structural perfor-
mance when compared to properly engineered foundation systems. Hybrid structural modifications can impair or
damage “healthy” slab-on-grade foundation systems.
-16- Common “rogue” sources of water can be house supply/drain line plumbing leaks, irrigation water supply line leaks,
flooding (rising water), or stormwater run-off ground/concrete deck/sidewalk/driveway surface accumulations (ponding
water).
-17- A structural foundation forensic assessment is a detailed examination of the foundation system to determine the ori-
gin and cause of structural foundation distress or failure. The foundation's service history, topography, and present behav-
ior are taken into account. Invasive testing/analysis may be required to complete the forensic analysis. Foundation struc-
tural remediation measures are addressed as needed. Cause and origin findings are documented in a detailed engineering
report.
-19- Surface drainage shall be diverted to a storm sewer conveyance or other approved point of collection that does not
create a hazard. Lots shall be graded to drain surface water away from foundation walls. The grade shall fall a minimum
of 6 inches within the first 10 feet, and in any case shall fall to allow positive drainage away from the structure. Impervi-
ous surfaces within 10 feet of the building foundation shall be sloped a minimum of 2 percent away from the building
(IRC).

Page 6 of 6……..….…..…..…....Form TXASCE-A-Rev. V7-2017….Copyright © 2001-2017 Lineberger Consulting Engineers, Inc…All Rights Reserved.


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