building foundations l.
Skip this Video
Loading SlideShow in 5 Seconds..
Building Foundations PowerPoint Presentation
Download Presentation
Building Foundations

Loading in 2 Seconds...

play fullscreen
1 / 36

Building Foundations - PowerPoint PPT Presentation

  • Uploaded on

Building Foundations. Foundation Walls. A base Monolithic construction Independent construction. Footings. Spread footings Undisturbed soil. Foundation-Wall Footings. Prevent settling or cracks Minimum of 12” below grade. Below frost line Thickness = thickness of foundation wall

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Building Foundations' - Sophia

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
building foundations

Building Foundations

Foundation Walls

A base

Monolithic construction

Independent construction

footing design
Prevent settling or cracks

Minimum of 12” below grade. Below frost line

Thickness = thickness of foundation wall

Width = 2x thickness of foundation wall

Footing Design
footing reinforcement
Rebar embedded

2 lengths of ½” diameter (#4) rebar

Positioned minimum of 3” above bottom

Footing Reinforcement
footing forms

steel, lumber, or combination of lumber & plywood.


Footing Forms
footing drains
4” diameter pipes at base of footing

Carries water away from house.

Sloped at least 1/8” per foot

Landscaping Fabric

Footing Drains
poured concrete foundation walls
Durable & water resistant

Most building sites

Support any type of house

8 –10” thick

Min. compressive strength 2500 psi

Most 8’ high

Poured-Concrete Foundation Walls
full height walls

Reusable forms


Full Height Walls
standard wall forms
Wood or metal

Built on site

Prefabricated forms


3 –7 days

Standard Wall Forms
insulating wall forms
ICFs (Insulating Concrete Forms)


Basic components

planks, sheets, or hollow blocks

Standard wall

Grid wall

Insulating Wall Forms
Poured continuously without interruption

Cold joint

Water content

Remove Air pockets

Concrete vibrator (stinger)

crawl space walls
Advantage – reduced cost

Soil cover



Piers support

Crawl-space Walls
sill plate anchors
Anchor bolts

Metal strap anchors

Sill sealer

Sill Plate Anchors
foundation wall details
Special features:

Brick-veneer siding

Utility Sleeves

Foundation Wall Details
foundation vents and windows
Metal vents

Rust-resistant steel frame windows

Wood framing (pressure treated)

Foundation Vents And Windows
stripping and maintaining forms
Wood wedges (no metal pry bars)

Stiff bristle (not wire) brush

Form-release agent – Bio-slick

Stripping and Maintaining Forms
moisture protection
Bituminous (tar) coating

Top of footings to finished grade level

Moisture Protection
Filling in excavation area

Too soon, push in foundation walls

First floor framing

Temporary bracing

concrete block walls
Popular for foundation walls

No formwork

Blocks inexpensive

Work stopped and started

Concrete Block Walls
concrete block basics
Concrete Masonry Unit (CMU)

Head Joint

Bed Joint

Common bond


Protect from freezing & moisture

Concrete Block Basics
Mortar bond strength depends on:

Type & quantity

Workability, or plasticity

Surface texture bedding areas

Rate at which masonry units absorb moisture from mortar

Water retention

Skill of person laying block

mortar mixtures
Portland cement, hydrated lime, sand, & water.

Prepackaged mortar mix

Type N

Type M

Type S

Type O

Mortar Mixtures
mixing and placing mortar


2 ½ hour when air temp is 80ºF or higher

3 ½ hours when air temp is below 80ºF.

Mixing and Placing Mortar
laying block foundation walls
Skilled masons

Corners built first

Story pole (course pole)

Laying Block Foundation Walls
tooling the joints
Weather tight joints & neat block walls

“Thumbprint hard”

Tooling compacts

Head joints, then bed joints

Tooling the Joints
Colorless & odorless radioactive gas

Extremely toxic

Lung cancer

Soluble in water

9X heavier than air

radon resistant construction
Gas-permeable layer

Soil-gas retarder


Vent pipe

Cap course

Radon-Resistant Construction
  • What is the minimum depth required for an exterior-wall footing?
  • Describe the type and position of reinforcement that is commonly added to strengthen a footing.
  • What is a keyway and how is it formed?
  • For nearly all poured-concrete foundation walls, formwork must be constructed for each wall face. What holds the formwork together?
  • What creates a cold joint?
  • Why are the joints in a concrete block wall tooled?
  • When using mortar, why is it helpful to know the differences between hydration and evaporation?