Module 3 Study Guide
What are brick or block points and who installs them?
Engineer installs them to identify a precise point the foundation wall must sit on the footer
What is meant by the term house setting?
Establishing the relative elevation of a house on a lot utilizing economics, functionality, and appearance.
Where should any excess concrete be unloaded?
The concrete plant
What is meant by parging a block foundation? What is the purpose of parging a block wall?
The application of a thin coat of mortar and cement to the exterior of a foundation. It is used for waterproofing and to make the foundation look nicer
What is a foundation overdig?
The area excavate beyond the dimension's given for the actual footer. It enables the footer and poured wall contractors the freedom to work safely.
Who is responsible for this error?
The contractor
How do we determine the locations for control joints?
The blueprints
Define below-grade block:
Block located below the finished grade
Define sub-grade block:
Block located below the normal footer level
How would you determine if a footing is level?
Builder's level or laser level
How does the poured wall subcontractor ensure that the walls are straight and level?
By using a builder's level and string lines
When should exterior concrete not be poured in the winter?
Cannot pour on frozen ground, frost, or mud. Typically below 28 degrees
What type of block should be used on the top course?
Cap block
You discover during your house setting that an option sold (ex: a walkout) will NOT work on the home site. What should you do?
Contact the customer and sales rep to discuss whether the customer would like to switch lots or remain on the same lot but without the walkout.
You discover a stakeout error during your house setting. What should you do?
Contact whoever conducted the original stakeout and allow them to correct their error. Once they have finished, recheck their work.
True or False: The house setting may be done prior to, or after the Pre-Construction Meeting, depending upon the project manager's time schedule.
False
Where might we need to have a footing bulkhead?
Garage, townhouse steps, walkout
What is underpinning a footer?
Giving more support to the footer so it doesn't shift
What procedure should be taken in your area in locating utility lines before digging?
Have excavator call prior to digging
How are weep holes for a block foundation used?
Holes to allow any moisture that may have penetrated to escape
What is the cut?
How deep you need to dig
What is a crawlspace foundation?
Masonry or concrete at a height of at least 32" to 40" above designed footer, with the area inside unconditioned or conditioned
What is slab construction?
Masonry or concrete combined with compacted fill and a concrete slab, cast in place to the proper dimensions of the house
Describe the process used to "lay out" a footing using the excavation hubs
Measure from the stake to the pin in footer
How would you determine if a footing is square?
Measure the diagonals
What is the acceptable tolerance for a foundation that is out of level and out of square?
Out of level: +/- 1/4" Out of square: +/- 1/2"
Describe a frost line:
The depth below the ground that water will freeze in a given area
What is the building setback?
The distance any building must sit away from the property lines. Building any permanent structure beyond the setback is prohibited.
If utility lines are damaged, who is responsible for them?
The excavator
If the excavation is not to phase specifications, who absorbs the cost to correct?
The excavator. We backcharge them
What is an interior footer drain, and where should it be placed?
Part of the drain tile system that is along the inside wall of the footer. It connects to the exterior drain tile and sump pump (if applicable)
Draw a diagram showing the proper installation of a foundation drainage system and label all components:
Perforated pipe at center of footer, covered with 57 wash gravel and filter fabric
What does P.S.I. indicate?
Pounds per square inch (used to find the strength of concrete)
When must all debris be removed from the foundation overdig?
Prior to the backfill
What methods of concrete delivery are used if access is not possible?
Pump trucks
How do you determine the size (dimensions) of a stanchion pad?
Read the foundation prints
What establishes the final grade, and who is responsible for it?
The site plan establishes the final grade which was found by the engineer. The project manager and excavator are responsible for final grading
Where would you find the details for a concrete driveway apron?
The site plans on street / apron cross sections
What are dig stakes?
These are set on the field stakeout and set the boundaries for the excavator to dig.
True or False: All ground vegetation is to be removed from the interior of basement and garage areas
True
What is a footing bulkhead?
Transfers weight distribution between different footer elevations. Used when there are changes in elevation. Ex: Garages or walkouts
You are field setting a house. The elevation of the start of the driveway is 503.9, the elevation at the weather lip is 506.6, the driveway length is 32'. What is the slope of the driveway?
Rise / Run 506.6 - 503.9 = 2.7 2.7 / 32 = 8.4%
What should you do with topsoil that is on the lot?
Scrape it off and save it for grading after the backfill
At what point is it appropriate to remove the poured foundation wall ties? (In the summer and winter)
Summer: 24 hours Winter: 48 hours
On a poured foundation, how long must the concrete set before the forms can be stripped? (In the summer and the winter)
Summer: 24 hours Winter: 48 hours
What is the purpose of foundation anchors (bolts or straps)?
TO connect structural and non-structural materials such as the framing to the foundation
How do you determine the height to waterproof?
Take your FF minus your flooring system to find your TOW. Subtract your proposed grade from TOW.
What is the maximum slope per code that we should allow on driveways?
14%
What is the acceptable percentage of calcium that can be added to concrete during cold conditions?
2%
What is the minimum driveway slope that we should allow on NVR driveways
2%
What is the minimum slope needed on a driveway for water drainage?
2%
How far away are spoil piles required to be placed away from an excavation?
2'
What in the minimum overdig in your area for a crawlspace foundation?
2'
What in the minimum overdig in your area for a kneewall foundation?
2'
Within what time period should the footing form material be removed?
24 hours
How many cubic yards of dirt will be removed from the 25' x 50' excavation shown above?
25 * 50 = 1,250 * 4.25' = (5,312.5 ft^2)/27 = 197 yards^3
What is the standard P.S.I. concrete strength in your area for footings?
2500 P.S.I.
How many points of access are needed for concrete delivery on poured foundations?
3
What in the minimum overdig in your area for a full 8' or 9' foundation?
3'
When grading a home, how far away from the foundation should a piece of equipment stay?
3'
What is the PSI of basement concrete?
3,000 PSI
What is the PSI of exterior concrete?
3,500 - 4,000 PSI
What is the average cut for the following excavation: Top left corner: 4' Top right corner: 5' Bottom left corner: 3.5' Bottom right corner: 4.5'
3.5' + 4' + 4.5' + 5' = 17'/4 = 4.25'
What is the spacing, per code, for foundation straps?
3.5' on center and 1' from corners and openings
What is the typical width of a mortar joint?
3/8"
Using the given dimensions, calculate the cubic yards of concrete needed to be supplied for this basement slab: Length: 32' Width: 20' Slab thickness: 4"
30'8 * 18'8 (subtract 8" from each wall for foundation walls) * 4" 30.67 * 18.67 * .33 = 188.9 188.9/27 = 7 yrds^3
What is the minimum frost line in your geographic area?
36"
How thick should the gravel base be under concrete in your area?
4"
What is the minimum thickness for a concrete driveway?
4"
What is the required finished thickness of the concrete floor in the basement?
4"
What is the diameter of #4 rebar?
4/8"
How many days after a foundation is poured should you wait before backfilling?
5 - 7 days
How many standard size brick does it take to cover one block?
6
What is the minimum slope required per code away from the foundation in the first 10'?
6"
What is the spacing, per code, for foundation bolts?
6' on center and 1' from corners and openings
What is the thickness of the poly located under the basement slab and what is the purpose of this poly?
6-mil poly used as a moisture barrier
What is the diameter of #7 rebar?
7/8"
How many cubic yards of concrete are needed to pour the same 8" by 76' by 8' foundation?
76' * 8' * .67' = 405 ft.^3 405 / 27 = 15 yds^3
How far below the top of foundation must the finished grade be per code?
8"
How much earth should be left unexcavated for frost protection on a two-day excavation
8" - 12"
How far below the bottom of the lowest framing member should the final grading be held at a minimum? Why?
8" per code and is for moisture and termite protection
What is the face dimension of a concrete block?
8" x 16"
If an 8" block wall is 76' long and 8' high, how many 8" total blocks, cap block, and regular block should be ordered?
8' * 1.5 = 12 rows 76' * .75 = 57 blocks 12 * 57 = 627 Total block = 684 Cap block = 57 Regular block = 627
If a footing is 8" x 16" x 130' lineal feet, calculate how many cubic yards of concrete should be ordered
8/12 = .67' 16/12 = 1.3' .67' * 1.3' * 130' = (116.13/27) = 4.3 yds^3
What is a track loader?
A heavy machine with a front metal bucket used for digging and loading material such as dirt, sand, rubble, etc.
What is a bulldozer?
A heavy machine with a front metal plow used to push quantities of material such as soil, sand, rubble, etc.
What is a bed joint?
A horizontal mortar joint at the bottom of masonry units
What is an expansion joint, and what is its purpose?
A joint that allows for the expansion/contraction of the concrete
What is a brick ledge and what is its purpose?
A ledge built into the foundation wall to support brick
What is a story pole?
A leveling rod that is paired with the builder's level to check elevations.
What is a full 8' or 9' Masonry foundation?
A masonry or concrete foundation wall on all sides and has a full in-ground basement
Describe a poured foundation wall tie and its purpose:
A metal strip used to hold aluminum wall panels apart from each other. Must be removed after stripping the forms
What is a beam pocket, and how is the size determined?
A notch in a foundation wall to hold a horizontal structural beam. The prints will give dimensions and tell you where it's located
What is a keyway and what size should it be?
A notch or groove in a footer or poured wall designed to provide a channel for the concrete to tie into. 1 1/2" deep by 3 1/2" wide
What is a benchmark?
A point of reference by which something can be measured. A permanent structure such as a manhole which can help set elevation.
What is a stoop bracket or haunch?
A protrusion or arm of the foundation that is provided to support the weight of a slab
What is the purpose of a retaining wall? Give an example of when it may be used:
A retaining wall is used when you need a drastic drop in elevation over a short distance. It may be used when building a community on a steep hillside
What is a structural slab?
A slab poured with reinforcing rebar rods and piers
What is a trowel?
A smooth and flat tool used to shape and smooth the concrete
What is a jointer?
A tool that cuts the control joints
What is an edger?
A tool used for smoothing edges to provide rounded corners on the concrete
What is a bull float?
A tool used for spreading/smoothing the slab
What is a screed?
A tool used to level off concrete between forms
What is a control joint in a basement slab?
A tooled joint in the concrete slab that tells the concrete where to crack
What is a builder's level?
A type of level used to set level points and check elevation.
What is a head joint?
A vertical mortar joint between ends of masonry units
Concrete poured at a high slump can cause what problems: Choose all that apply A. Excess cracking B. Increased PSI strength C. Decreased PSI strength D. Long-term or expensive service issues
A, C, D
You are now in the field setting a house. Using the information provided below, determine the following for this foundation: A. BOE B. Average Cut C. Cubic yards of dirt excavated Length: 64' Width: 36' BF: 735.7 Elevation top left corner: 741.5 Elevation top right corner: 739.1 Elevation bottom left corner: 740.7 Elevation bottom right corner: 738.3
A. 735.7 - 0.67 = 735.03 B. 741.5 + 739.1 + 740.7 + 738.3 = (2,959.6)/4 = 739.9 - 735.03 = 4.87' C. 70' * 42' (must add 3 feet to each side for overdig) * 4.87 = (14,317.8)/27 = 530.3 yrds^3
Define the term striking a mortar joint:
Adding a smooth indentation to the mortar joint which prepares the wall for parging
What is a field stakeout?
Adding stakes to a property to serve as a reference point. These stakes include property lines, public utilities, building setbacks, building markers, etc.
If we are building on a wooded lot, when should we have the engineer stake out the house for construction?
After the trees are cleared off the lot
When should you brace a block foundation?
Always before backfill (every 10')
What is meant by air entrained concrete?
An admixture used to entrain microscopic air bubbles in concrete which allows water to pass through
In reference to a retaining wall, what is a deadman and what is its purpose?
An anchor, buried in the ground to which the retaining wall is tied in. It helps prevent the wall from bowing
What is the Right of Way (R.O.W.)?
An area owned by a municipality or HOA that meets customer's property line and typically includes the tree lawn, road, and sidewalk.
What is a spread or float footing?
An unformed footer used when poor soil conditions exist (larger depth and width and contains rebar)
When a basement foundation is installed in an excavation it creates a trench scenario. At what depth will that trench require workers to be protected?
Anything over 4'
When and where do we use insulation in our slabs?
At or above the frost level
When are walks and driveways cut?
At rough grade
When is a driveway excavated for a house with an integral garage?
At the start of excavation
Are brick wall ties needed on a brick to grade application?
Yes
Do you need extra concrete for footing bulkheads?
Yes
Should stone be used to encompass the footing drain?
Yes
Should you parge and waterproof below-grade block?
Yes
On blocks that are going to be parged and tarred, should the joints be struck?
Yes, they should be struck prior to parging
Excavation is to be level within _________________
+/- 1"
What are the maximum tolerances for a footing that's out of level?
+/- 1/4"
What are the maximum tolerances for a footing that's out of square?
-1/2"
What in the minimum overdig in your area for a slab foundation?
0'
A control joint in a 4" thick slab should be how deep?
1"
What tools/equipment are needed to properly check an excavation?
1. 100' tape measure 2. Builder's level or lock level 3. Topo 4. Phase specs and checklist 5. Blueprints
What are some indications or conditions that may necessitate a change to the "normal" footing?
1. Bad ground 2. Code change
Name 3 things that should be considered when excavating a foundation that has excess dirt:
1. Can the house elevation be adjusted to minimize hauling? 2. Where will the dirt be hauled to? 3. Coordinate to have trucks on site hauling while digging
What tools are needed to check a foundation?
1. Checklist 2. Builder's level 3. 100' tape 4. Blueprints 5. Topo/SAR
What types of equipment are used to grade a typical lot?
1. Excavator 2. Bulldozer 3. Bobcat
What phases should be completed before backfilling for a rough grade?
1. Footing 2. Drain tile 3. Walls 4. Waterproofing 5. Downspout conductors
Briefly describe two ways a footer drain can be relieved?
1. Gravity fed by daylighting the drain tile 2. Mechanically with a sump pump
What PPE is required for those cutting hardened concrete?
1. Hard hat 2. Glasses 3. Respirator 4. Hearing protection
List 5 safety precautions when dealing with the phases of excavation, backfill, and final grade:
1. Have proper access into excavation every 25' 2. Maintain 10' clearance from overhead power lines 3. Keep spoil piles 2' away from excavation and equipment 3' from excavation 4. Make sure all backup alarms are working for off road equipment 5. Use proper sloping/benching 6. Keep workers away from equipment
List the necessary tools required to set a house.
1. Laser level 2. 25ft and 100ft tape measure 3. Blueprints 4. Plot plan/Topo 5. Site plan 6. Marking paint 7. Builder's level
Name 2 ways to protect an excavation from freezing:
1. Leave excavation 8" - 12" high 2. Protect footing area with straw and poly or concrete blankets
What PPE is required for those placing and finishing concrete?
1. Long sleeve shirt 2. Pants 3. Glasses 4. Hard hat 5. Gloves 6. Rubber boots
What are some secondary considerations for house setting?
1. Minimizing excavation and hauling 2. Minimizing gravel fill 3. Observing municipal zoning and building regulations 4. Placing footer on firm soil 5. Following FHA or VA regulations
Referring to the question above, name 2 ways an excavator can attempt to protect the workers:
1. Not allow anyone to be in trenches while excavating 2. Proper sloping/benching 3. Access from trench every 25'
List 3 possible solutions for resolving rock problems when excavating a foundation
1. Raise the house 2. Use a hammer hoe to break the rock 3. Blasting
What are the three primary factors to consider for house setting?
1. Slope of driveway 2. Depth of sewer 3. Surface water drainage
Since equipment should not travel on pavement or curbs without protection, what types of things can be used for protection?
1. Tires 2. Rubber mats 3. Wooden planks
List 5 things that should be checked on a foundation:
1. Wall height and length 2. Beam pockets 3. If it's level 4. Diagonal dimensions on plumb 5. Pads
What are some misc. items that should be marked on the footing/foundation plan for the footing contractor?
1. Where to add sleeves (if applicable) 2. Where to add rebar hooks for wall bracing 3. Stanchion pad location 4. Elevation 5. Frost footing location
When stockpiling fill is necessary, what should be taken into consideration?
1. Where to put the pile 2. Does it need to be hauled 3. How to stabilize dirt to prevent erosion 4. How long it will sit there
What are the maximum tolerances for a footing dimensional (diagonal)?
1/2"
Calculate the following cubic yards of concrete that need to be supplied for a driveway that is 10' wide, 48' long, and 4" thick:
10' * 48' * .33' = 158.4' 158.4' / 27 = 5.8 yds^3
What is a lock level?
A hand-held builder's level
What is a conventional footing?
A 4" x 4" trenched and formed footer
What is an excavator?
A heavy machine with a boom, dipper, bucket, and cab on a rotating platform. It is used for digging and moving material such as dirt
What is a plot plan?
A birds-eye diagram of a house on a property set at a defined scale created by an architect, surveyor, or engineer. It provides info such as the building setback, utility runs, property lines, elevations and grading, and any other major features.
What is a whaler and what is its purpose?
A brace used to support and straighten wall forms
What is a swale?
A channel created to manage water runoff which helps with drainage by preventing water pooling and erosion
What is a kneewall foundation?
A combination of masonry or concrete, along with a frame wall, which creates a minimum 96" high wall
What is curing compound?
A compound used to reduce evaporation from the concrete
What is a stanchion pad?
A concrete pier used to support a stanchion post or steel "lolly" column
What is meant by the term cold joint and how should it be treated?
A delay in the second pour. It can be treated with hydraulic cement and waterproofing
What is a footing? Describe the purpose of a footing?
A flat level surface made of concrete that disburses weight and provides a level surface for building
Who is responsible for house setting in your market?
Aztech Engineering and Surveying Company
How does the NVR dirt tool tie into the house setting process?
Based on the lot specifications, it will tell you whether you will be heavy or light on dirt. To help balance your dirt, you can make slight adjustments to the structure's elevation.
What happens first, the footer drain system or waterproofing the wall?
Footer drain system
What is a frost footing?
Footing used in a low grade condition which extends below the depth that the ground will freeze
Describe how poured foundation walls are protected from freezing in your area:
Foundation blankets
What is meant by the term blow-out when referring to poured wall foundations?
If the forms are blown out when they pour
In your area, how are the poured foundation wall ties sealed to prevent water penetration? (Inside and outside)
Inside: N/A Outside: Waterproofing
What types of house setting issues can occur when working in a community with multiple builders? What measures should you take in these situations?
It can affect drainage and also curb appeal. To prevent this, you should make sure all builders are using the site plan and building to proper elevations.
What is meant by daylighting a foundation drain?
It is gravity fed so the end of the drain is exposed to daylight down hill of the foundation
What is a weather lip at a garage door and what is its purpose?
It is the lower portion of concrete at the entrance of the garage door and is used to seal and protect the garage from the outdoor elements
What should be done with extra concrete in the truck?
It should be returned in the trucks to the plant
What is a slump test and what is the maximum slump permitted by NVR?
It tests the consistency / strength of concrete by running the concrete through a cone shaped tool. The max slump permitted by NVR is 5"
How could we avoid using a pump truck to pour footing concrete?
Leave the area clear and have access points for the cement mixer
For an 8' tall foundation, what is the elevation between the top stanchion pad(s) in relation to the top of the perimeter footing?
Level with each other
What is the maximum driveway slope that we should allow on an NVR driveway and does that differ from your local code?
NVR max is 14% but local code is 10%
Do we use an interior footer drain in a sub-grade block condition?
No
Should you parge and waterproof sub-grade block?
No
What is a bobcat?
Small machine with front bucket (or other attachments) used for grading, moving stone, etc.
What is meant by facing concrete
Smoothing the vertical edges
Why should snow not be removed until you are ready to excavate?
Snow acts as an insulator
What is rebar?
Steel bars used as a tension device set inside the concrete form to reinforce concrete strength
What is "spalling"? What conditions cause this to occur?
Spalling deteriorates the surface of concrete and can be caused by the freeze/thaw cycle
What is an offset hub?
Stakes placed as reference points off to the side of your structure that indicate where your structure will be placed.
What is the purpose of a foundation drain?
To allow water to drain from around or under the foundation which prevents standing water around the foundation
What should be accomplished by the rough grading a lot?
To create a clean and livable lot that is able to properly drain water away from the house
Why should excess fill be removed from the lot during excavation?
To reduce hauling costs so that you don't have to pay excavators at a later date to come back and haul the dirt away
What is the purpose of the 6-mil poly under a concrete slab?
Vapor barrier
What is meant by the term honeycombing and how should it be treated?
When cement isn't mixed well or sticks to the forms and creates a textured pattern. It can be treated with hydraulic cement
What is a balanced grade?
When everything we dig is used for the backfill and grading so no hauling is necessary.
When would a concrete pump be needed when pouring interior concrete?
When you have limited access points to the foundation