Foundation Build Detail

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Procedure

1. Collect materials and cut stakes
• [28] 2x6 support pieces
• [2] 2x8 connectors, 3’
• [6] 2x8s, 16’ long
• [56] stakes, 2x2-2x4 dimension, 16” long
• 1.5 and 0.5 spacers for height
• 16’ scree board for gravel height
2. Make forms in general area, with 16’x32’ interior, no supports yet
• Use ‘successive overlap’ with full length 16’ boards
• Save unnecessary cutting-to-length
• Mark 16’ and 32’ on boards so boards are a measuring stick
• 6 long boards
• Connect the 32’ pieces together
3. Triangulate. Adjust corners as needed, do not fix anything
• Put in a screw in corner to hang measuring tape
4. Add leveling stakes.
• Run string on the outer edge of 2x8 form, but don’t touch form anywhere
• Add wedges or blocks to raise foundation as needed
• Use 2x6 supports, every 4’

Slight overlap on each corner as boards are >16’

1. Interior size
2. Triangulate
3. Level

Inset 2” so that level stakes can be added

String on stakes detail

As Built

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Procedure

• 8” down - insulation - installed by scraping down with tiller
• Just enough to bury insulation 2” or so - ,meaning from 7” down (1” below grade) we dig 3” to make it 4” below grade, top of insulation is at 2” below grade - so we are buried about 2” or more as we slop down 1” over 2’ for drainage

Shallow Frost Protected Footer Strategy

Frame up, then fill inside.

• 16x32 area
• Use 2x8 lumber forms. $33.10 for 16’ at Cameron Lumber, $24 at menards
• 4” gravel - 924 sf - 11.4 yards
• Drainage strategy: the whole structure is elevated on a pad. Final drainage through gravel around the sewer pipe

Concrete Quantity

• 4” over 16x32, but using 2” EPS so 15-⅔ x 31-⅔ feet = 496 sf *.33 = 165 cu ft = 6.11 yd
• Rim - extra 14”. 1.16’*2(31-⅔ +15-⅔)= 109.8 cu ft = 4.1 yds
• 10.2 yds total without extra.
• 3-5% extra is typically called for
• This means 0.3 to 0.5 yard
• This one says add 1 yard for 10 yards
• This one says 5-10% extra

Real Life

• ½ due to slope of edge, 9/14 due to partial depth- 1.3 yards
• If just take ½ due to 45 deg slope - 2 yards
• 8 yards total no extra - 8.8 yards with 10%, 8.4 with 5%
• 7.4 yards total no extra - 8.1 yard with 10%. 7.8 with 5%
• And one last time: 1.5 yd + 6.1 = 7.6 yards
• 8.4 yd with 10%, 8.0 with 5%
• Or

Grade is set for 32’x64’ area. First, verify grade with laser.

Make forms- 16’x32’.

2x8 lumber

8”

Wedge to elevate foundation form. Poly if need to close leakage gaps

Mark 4 corners with rebar stakes. Use string, triangulating for a perfect square.

String

Gravel

Remove string on gravel side, rough spread gravel.

2x4 stakes, 16” long

14”

Dig 14” footers

Shallow Frost Protected Footer Strategy - 2

Dig 14”

Test and bury plumbing

Spread gravel including under footing. Scree the gravel with a board to get 4” thickness. Compact the gravel. Put in the box for the plumbing exit under the tub.

Add insulation, screw in to forms from the outside. Add the mudsill anchors, screw them to the top of form and top of insulation.

Add vapor barrier. Add aperture 16” long and 15” wide inner dimension after wood form, using 2x8 lumber. Needs tub overflow pipe to be shortened 2”. Add slab thickening under stairs. Add rebar. Add chairs..

Shallow Frost Protected Footer Strategy - Original Idea

Frame up, then fill inside.

• 16x32 area
• Use 2x8s. $33.10 for 16’ at Cameron Lumber, $24 at menards
• 4” gravel - 924 sf - 11.4 yards
• Drainage strategy: the whole structure is elevated on a pad. Final drainage through gravel around the sewer pipe

Grade is set for 32’x64’ area. First, verify grade with laser.

Make forms- 16’x32’

2x8 lumber

10”

8”

Dig 10”

Wedge if need to elevate foundation form, or poly if need to close leakage gaps

Dig 14”

Test and Place plumbing

Mark 4 corners with rebar stakes. Add string, triangulating for a perfect square.

String

Gravel

Shallow Frost Protected Footer Strategy - Original Idea

Frame up, then fill inside.

• 16x32 area
• Use 2x8s. $33.10 for 16’ at Cameron Lumber, $24 at menards
• 4” gravel - 924 sf - 11.4 yards
• Drainage strategy: the whole structure is elevated on a pad. Final drainage through gravel around the sewer pipe

Grade is set for 32’x64’ area. First, verify grade with laser.

Make forms- 16’x32’

2x8 lumber

10”

8”

Dig 10”

Wedge if need to elevate foundation form, or poly if need to close leakage gaps

Dig 14”

Test and Place plumbing

Mark 4 corners with rebar stakes. Add string, triangulating for a perfect square.

String

Gravel

Form Design - Top view

Cover screws with tape to get them out later

Stake

2x8 formwork

2x8 supports every 3-4 feet

Future notes - 3D printed forms for Rosebud, ¼ the concrete used. Rosebud uses 10 yards. Back to stem walls with spread footer. They are designed to hold insulation, rebar supports, and stakes. They are also designed to hold insulation, and to protect the insulation afterwards, thus minimizing the labor associated with the foundation significantly.

Heated

Unheated

Future Work - Solar Concrete

Future notes - 3D printed forms for Rosebud, ¼ the concrete used. Rosebud uses 9.7 yards. Back to stem walls with spread footer. They are designed to hold insulation, rebar supports, and stakes. They are also designed to hold insulation, and to protect the insulation afterwards, thus minimizing the labor associated with the foundation significantly.

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For Rosebud, we need 1 cu ft of concrete per foot of foundation length - or 32+32+15+15 - or 94 cu ft. Total of 3.5 yards of concrete, and this can be self-poured.

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45 bags of 80 lb readimix.

60 60 lb bags. $3.30/bag - $198.

Portland - $11/94 lb.

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7 bags of portland - $77 + $20 + $20- around $117 in materials if you mix your own. Thus, about $400 in materials for the foundation.

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Put the savings into running PEX under the floor for a high quality living experience.

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How about solar concrete?

1:7 ratio, 14% concrete.

• 4000 lb/yard
• 61 kg/day of solar cement
• That is 427 lb of solar lime concrete
• Need 10 days of production for one yard of lime concrete.
• This means 35 days for one Rosebud foundation with stem walls

The foundation would need to be engineered, as we’re using 1450 psi lime concrete if no pozzolanic material is added.

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Also - pad foundation accepts 1450 psi C10 concrete. Idea

Heated

Unheated

4” gravel

4” gravel

6” Lime

Concrete

Pad

Backfill

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vinyl flashing

Frost Protected Shallow Foundation v2

¼” cement board

2” EPS

technical: foundation: slab-on-grade: construction detail

frost protected shallow foundation - v1

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Do we need to seal panel?

New Foundation Detail - Part 1 - Formwork

Design

• Galvanized steel - lasts 50 years
• Aluminum nobility is higher than zinc (galvanized steel)
• Galvanized steel is worst flashing for corrosion?
• Use PVC flashing.
• No form release agent needed - forms are against insulation.

8” Flashing ends at form

Insulation 18” Tall

2” EPS

Graded, Compacted Grade

2x8 Foundation Form

18”

4” slab

4” gravel

10”

12”

12” Cement Board

Needs sharp shovel

Mudsill Anchor

New Foundation Detail - Part 2 - Forms are 32’x16’ on the Inside

Design

• Galvanized steel - lasts 50 years
• Aluminum nobility is higher than zinc (galvanized steel)
• Galvanized steel is worst flashing for corrosion?
• 1” insulation
• No metal. Use PVC flashing for bendability, saving work.

Graded Grade

Infill insulation

10” pvc flashing

(16.5 min)

10”

8”

8”

20” total of insulation

Needs sharp shovel to cut soil down

15” Distance from grade to last bend

4” below graded grade. 12” strips of cement board appear to be the best choice.

Flashing

14” $1/ft 0.01”

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10” vinyl flashing. Tupically used as through-wall flashing.

$27 Lowes

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24’x50’ 0.018” thick $76

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PVC aluminum $99

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How about PVC flashing?

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0.01”x12”x50’ $24

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Note that pressure treated lumber corrodes aluminum and galvanized steel.

TPO roofing membrane. $0.6/sf

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Cement board protects insulation. ¼”, 16 sf

$0.56/sf

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Flexible flashing can be non-adhesive, so it can be applied at any temperature. The word is that the adhesive should not be relied on for moisture blocking.

Final Finish

Landscape fabric +

gravel

Up to 2’ away from the house keeps weeds from growing next to the house, and makes any termite infestation visible.

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Termites and Rodents

Termites -

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Physical block of termite tunnel.

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More about Termite shields

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Control Joints for Concrete

How to test soil under slab?

• ‘Our team will test the ground and soil under the concrete slab to make sure that the structure beneath the concrete is solid before we start pouring the concrete itself.’

Soil Testing

Where to put them?

• Relief cuts at 24-36x slab thickness, or 10-18 feet apart.
• Depth is ¼-⅓ slab thickness - 1-1.3” for 4” slab
• Cut to the depth of diamond tooth - in video to the right it’s ¾”
• In video, I am observing about 4” of cut in 4 seconds at about ¾” depth, or conservatively 2” of cut. ½-1 IPS.
• For a 16’ cut - 192” - that is 3-6 minutes, acceptable.
• If we do 2 passes, we are talking 6-12 minutes
• Pattern - it should be on all corners

Cold Temp

• Concrete curing blanket stays on 3-7 days

Build Up

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Frame up, then fill inside.

• 30x40 foundation

Frame up, then fill inside

Lay 4” waste pipe to 4’ outside of foundation. Slope down 1” over 8’ per plumbing detail.

Option 1 In Full Detail

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Soil Moving

1. 500 cu ft soil = 18.5 cu yd of soil - 2 loads?
1. Cost - $300-450 for soil loads
2. Pad
3. Then bury the sides, add garage. As much soil as pad itself.

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Add soil to raise pad. Tamp it with tractor

Soil moving requires 3 steps: digging, depositing, and leveling at end. Final grading step requires a lot of soil

Forms, Anchors, Stubs

14”

Pour, Insulation, Poly Flashing

18” form

Vapor Barrier + 4” Gravel.

Terminate gravel 2’ out from pad

Backfill

Level backfill

Option 2 In Full Detail

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Dig down with Lifetrac. Pad is already tamped.

Soil moving requires 1.5 steps: digging and depositing pile at end of side.

Dig and bury the stubs and water line

Pour, Insulation, Poly, Flashing above poly

4” Gravel, vapor barrier, forms, anchors.

Level backfill

14”

18” form

18”

Need to backfill 2” to get bottom of footer 12” below grade

Option 3

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Dig down 12”. Pad is already tamped.

Insulate.

Bury.

Edge may be troublesome

So dig down and make 18” forms -

Next Steps

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Soil Moving

• 500 cu ft soil = 18.5 cu yd of soil - 2 loads?
• Pad
• Then bury the sides, add garage. As much soil as pad itself.

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Add soil to raise pad. Tamp it.

Lay 4” waste pipe to 4’ outside of foundation. Slope down 1” over 8’ per plumbing detail.

Option 1

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Option 2

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Dig down with Lifetrac. Pad is already tamped.

Soil Moving

• Dig 7.5 feet around, 128 feet
• 2 feet per bite - 64 bites
• Pour slab
• Then bury the sides, add garage. As much soil as pad itself.

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This still leaves final sloping step to be done at end.

Can we get away from final sloping step? Option 2 minimizes the final bury step.

Soil moving requires 3 steps: digging, depositing, and leveling at end. Final grading step requires a lot of soil

Soil moving requires 1.5 steps: digging and depositing pile at end of side.

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Pad

32x64

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Pad, 16x32

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48’

16’

1

2

3

4

Foundation Actual Build - Gravity Pond

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Soil Moving

• End up with energy-producing gravity pond
• Grade is 2’ from top to bottom
• Average 1’ of soil from the entire area.
• Left 6” from line, so it was 18” of soil added at bottom - so 9” on average
• ¾*64*32 = 1536 cu ft = 57 cu yds - about 2 hours of digging (guess, check in video)
• 44,000 kg of water over at least 15 feet high. MGH= 440k*3=1.32M joules.
• 800kJ of extracted energy at 60% water turbine efficiency.
• That is only 0.2 kW hr per day.
• Extrapolated - 10 hours of digging for 1kWhr of energy storage per pond - or 20 hours total
• If automated, this costs 20 gallons of fuel. Energy payback time for digging is -
1. 40kWhr per gal gasoline? 800 kWhr of gasoline equivalent.
2. 7kW PV array recovers this energy in 20 days
3. Self-payback by pond energy itself is 4000 days. Crazy, but still net positive.
4. Slow solar autonomous is an answer here - 2kW vehicles that are slow-moving, self-powered by their own PV panels

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1

2

3

5

71.6’

4

6

64’

32’

2

Foundation Actual Build

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Add soil + removal area becomes pond

Grade to flat. Runoff not considered here yet.

Slopes down unless area is flat.

Stake area of house + 8’ and determine level

To stake area:

• Start with one post, and string 3 sides. Leave one side open for access
• Start at 1. Move to second post - 64’
• Move to 3rd post - 32’. Put in 2 stakes at limits of angle
• Triangulate to 71.6’ away. Make the 32’ and 71.6’ point meet up before proceeding - using the range where the 2 stakes are located.
• Move to 5th point at 64 feet away. Put in 2 stakes for limits.
• Triangulate to fix point 5

1

2

3

5

71.6’

4

6

64’

32’

Foundation Detail

14”

Add soil to raise pad. Tamp it.

Lay 4” waste pipe to 4’ outside of foundation. Slope down 1” over 8’ per plumbing detail.

Vapor Barrier + 4” Gravel.

Terminate gravel 4’ out from pad

Add soil + removal area becomes pond

Grade to flat. Runoff not considered here yet.

Slopes down unless area is flat.

Stake area of house + 10’ and determine level

• Distance between holes in assembly - X
• This is important because once set in rough-in plumbing, we want to make sure the holes do not get bent out by more than 1” when buried for the concrete pour, as we have a 1” tolerance for the toilet
• Toilet Trigonometry:

Final Stub locations

1” tolerance to wall

13.5” + 5.5/2 = 13.5+2.75 = 16.25”

22.5”

27.8”

27.8”

27.8” OC

Waste Pipe

• Tub goes directly against framing
• Framing is 5.5” from edge of insulation

House Base

32x16 Including insulation

Red is stake for foundation corner

31’8”x15’8”

Tub starts 3.5” down from stake

Tub is 60” long so it ends 63.5” down from stake and midline of tub is 18” in from left (14.5” from edge of tub).

Waste pipe (4”) has 4.5” OD and is 0.5” from end of tub, so pipe begins at 64” on edge from Corner Stake

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48.5” from according to this

(Framing is 2x6 for water utility wall)

One Stick of 4”

Tub

Plumbing Rough-in

• (1) 4” waste, full stick - 18” used for toilet flange
• Up to (2) 3” stack. Cut off at 24”. 8” from center of tub drain to center of stack.
• Main drain Reduced with (3) 4-3” reducer bushing
• Curves with (4) 3” sweep elbow (get a short elbow in case)
• Expanded to (5) 3-4” closet elbow
• 4” pipe to toilet
• (6) 1” water line inside an (7) electrical sweep elbow
• (8) 2 4”caps and a 3” cap for pressure testing

Install of tub

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Drain kit install

Shower Drain

Foundation

Form, EPS, Stubs, and Pour

14”

Lateral EPS, Poly, Flashing

Lateral EPS, Poly, Flashing

• Grade. Grade for entire area of future expansion.
• Pile dirt in middle. For 512 sf of foundation - need 1-⅙ * 512 - 100 sf = 500 cu ft soil = 18.5 cu yd
• Bobcat should do a 1 yard per bucket
• Measured - 6’x3’x1.5’ is a yard easily
• CAT dirt bucket is 0.56 yd
• Should be an hour of work
• Concrete = 100 cubic foot perimeter (3.7 cu yd) and 6 cu yd for pad. About 10 total. 8 yard trucks, 10 if fully loaded.
• What kind of gravel to use and how much?

18” form

Add soil + removal area becomes pond

Grade to flat. Runoff not considered here yet.

Add soil to raise pad. Tamp it.

Slopes down unless area is flat.

Lay 4” waste pipe to 4’ outside of foundation. Slope down 1” over 8’ per plumbing detail.

Vapor Barrier + 4” Gravel.

Terminate gravel 4’ out from pad

Shallow Frost Protected Footer, 500 SF

Gravel Calculation

• 36x20 includes the 2’ of EPS insulation around the house
• We also need 6” of gravel in the garage/tractor park, 20x20 if include 2’ out
• Total of 52’x20’
• Frost protected shallow foundation calls for 4” of gravel
• Calculator says 13 yards. Trucks carry 16.
• If we do landscaping with gravel next to house - for another 2’ out, 2.5” deep with landscape fabric underneath.
• 136 feet x2 feet is 2 more yards
• Need 2 yards more total
• Take another yard for driveway into the tractor garage, followed by pervious pavement down the road from 3D printed forms.
• Use mix of fine and coarse aggregate
• This one says use smooth pea-gravel like material that is truly self-compacting. Sand is not self-compacting (when wet)
• Vapor barrier prvents water and rusting tools. Could be why my welding wire rusts.
• Sequence of soil prep
• Do not use sand above vapor barrier
• There is no such thing as self-compacting clean rock. It’s less problematic, but it still settles - the professional view, see one of last comments from PE
• ¼” per foot grading around house, or 1-2%. Or over 10 feet, 2.5” at 1%. Codes say 6” over 10’?

36x20

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Shallow Frost Protected Footer, 500 SF

32x16

16x20

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16x16

52’ long by 2’ wide

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52*2+16*2=136 feet long

Source

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Seed: Drains & Vents

W/D

20”

5.5”

15.5”

15”

15”

24”

24”

113.5”

60”

24”

18”

240”

vent stack

105”

2” rigid insulation

Factor e Farm : Rosebud

Water Shutoff

Can we stand tub on top of the floor, so we nee no foundation complication?

No, because somewhere the drain must go below floor.

Not 60 but 60 + wall

Toilet

Pictures - Seed Eco-Home

Plumbing Test - This is what the building inspector looks at:

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Use 90 degree elbows for water to prevent water line kinks

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Check out this auto ladder lift:

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Check Out This Scaffold - Migraine Craftsman

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Vinyl flooring - tongue and groove - $1.40/sf

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Ergonomic Analysis

Compact It + Vapor Barrier + 4” Gravel

Form, EPS, Stubs, and Pour

14”

Lateral EPS, Poly, Flashing

Lateral EPS, Poly, Flashing

Case of 1000 sf foundation: Grade and pile dirt in middle. Dirt is 1160 cu ft - 200 cu ft for edge so about 1000 cu ft, or 37 cu yd. Soil comes from future Gravity Pond.

Grade

Backhoe

18” form

• 42” vs 18” concrete lip
• Slab is 4”
• Take 38” vs 14” concrete for lip + 1000 sf * ⅓ cu ft/sf. 333 cu ft = 12.3 +0.6 yards = 13 yds. 8-10 yds/truck at $120-$150/yd
• Base cost is $1755
• 200 feet * 3.17 = 634 cu ft = 23.5 cu yds = $3172
• Take an average of $120 to 150. Around $135
• That’s right: just concrete is about $15/ft
• 2 x 500 sf has extra $500 in concrete cost + 64 feet more of form + labor.
• 200 feet * 1.17 = 234 cu ft = 8.7 yds = $1175.
• Total cost difference is - $1997
• Uninsulated concrete cost - $4927
• Insulated concrete cost - $2930

Uninsulated - Below Frost Line

Shallow Frost Protected Footer

Advantage - does not need to rip up area around footer for earthworks of the insulation burial. But, if we are building up from flat for SFPF, then there is no additional earthworks for the insulation - the insulation is laid on grade.

Mudsill Anchors - 26 Total

Updated for very final layout?

8 - corners

4 - ends of boards

6 - around doors

8- 6’ runs

TOC

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1. Step by step slab foundation - good one for slab with all the details
1. Good one, pictures. Specify 5% extra for concrete
2. Air entrainment - 5% for frost proof. Not for polished concrete.
2. How to do polished concrete
3. Step by step grading a site for a home
4. Step by step clearing forest for a house
5. How much space is required around a foundation to move equipment around
6. How to do a frost protected shallow foundation
7. How to do a raft slab - 6” of gravel removed, then insulation placed under.

Slab on Grade - Frost Protected Shallow Footer

Slab on Grade - Frost Protected

Compact It + Vapor Barrier + Gravel

Form and Pour

12”

• Slab on Grade including Shallow Frost-Protected Footer as a variation of slab on grade
• They also insulate under with Roxul for higher performance
• A raft slab is a frost-protected shallow foundation, or slab-on-grade, that does not include the standard thickened-edge footing on which the entire load of the house bears. It is engineered to distribute the load evenly over the entire building surface.
• FPSF
• Formwork for FSSF foundations - company
• More about Raft Slabs
• Designing
• More on FPSF
• Drainage at bottom
• Compact soil. Rental link.
• Form and pour

Polishing Concrete

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• Done after 28 days of concrete cure
• How to - 8 steps of finer grit process.
• Home improvement centers rent polishers
• Polished concrete is $3-20 per sf. Or $3-12/sf.
• $2-6/sf for basic polish or stain or seal
• Stain $50/gal for 200sf
• Sealer - $200/5gal

Raft Slabs

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• In Australia, they use raft slabs - slabs with footings under the building as well.
• Insulated foundations = raft slab. Rigid foam is 25 psi, so that is fine for 3000 psf load
• Raft slab on inclined creeping sand beds
• 3 types of shallow foundation - strip, pad, raft
• Pad
• Rafts
• Solid slab raft
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Slab Foundation

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• Prepare Site
• Create a house pad
• Deliver gravel
• Level Gravel
• Dig footer
• Make forms
• Rough-in utilities
• Pour
• Float
• Smooth
• Cut relief line down the middle

Leveling

• Scree first with a long board
• Go over poured concrete with 3.5 foot magnesium bull float (3:06)
• Trowel immediately after, but only after bleedwater is brushed off. (4:10). Troweling is done on knee pads. Floats are closed handle, trowels are open handle.
• Fresno - is a trowel with long handle. This is for speed. For harder surface, a steel trowel is used.
• Cut a joint - 3:39 - when wet. 3:48 - run a ½” radius edge. Could use ¼ or ¾.
• 5:18 - concrete curing compound if you can’t keep it moist
• Trick - used motor oil or other oil on forms to reuse them later.

With Footer

• Footing is simply dug, no forms around it
• Skid steer digs the footing by going down with bucket - no backhoe - for 2 feet deep. See plans.
• Pneumatic hammer used to dig deeper down to 2 feet for footer
• 2500 psi concrete, no inspection needed
• Only top 1 foot gets forms
• Sand-poly-sand. Bottom layer of sand for puncture proofing
• Rebar, bent, put down at bottom. Poly only goes to bottom of footer. Then rebar is hung - one near bottom, another near top. Etc.
• Note that plastic is welfare on one corner, but that is supposed to pass inspection.

Other details

• Plumbing penetrations - wrap them in plastic.
• Use 10-12 mil poly - less chance of getting holes in it.