1. UDC Inspector Seminar
2007
Understanding Manufactured Home Installation Standards

2. Presenter – Ross Kinzler
Executive Director of Wisconsin Housing Alliance
Presenter – Mike Zenner
Inspection Services

3. Ross Kinzler With MH industry since 1989
Chief lobbyist for the industry

4. Mike Zenner Over 35 years of manufactured housing experience
Wick Quality Control
Currently – Inspection Services
AC inspections under the HUD Code
UDC Construction and other creditials

5. What we’re going to learn
Basics of the HUD Code
Installation standard for existing homes
New HUD Installation Standard
New licensing law for installers

6. What’s in your book? Key to the Code Did you know? Commerce contacts
Web links
Older home installation standard info
Licensing info
New installation standard
Resources

7. What’s What
Home is covered by HUD Code which preempts state and local law
New installation standards preempt local ordinances just like the UDC
Pier installation standards are now a part of the UDC
Watch out for places where codes interface
Understanding the HUD Code

8. What is the Timeline Sept to March – training installers
Jan 1 –licensing in effect
Jan to April – training inspectors
April 1 – new code effective and inspections begin
Inspectors may not be employees of home manufacturer, a salesperson involved in the sale or an installer involved with the particular home

9. Critical Websites
See page 6

10. Licensing Trigger is installing a home on a foundation
Anchoring – no
Grading – no
Excavation – no
Pouring basement – no
The person supervising the home going on the foundation - yes

11. Licensing
General supervision – the installer does not need to be on the job site
Homeowner is exempt from licensing but if people help and would otherwise need a license they must be licensed

12. Licensing of Installers
Qualifications
18 years old
Not been found responsible in any court or agency hearing of a violation of the installation law during prior 2 years
Not been found responsible in any court or agency hearing for failure to perform under installation contract or defrauding a person in the provision of installation services

13. Application for Installers License
$100 license fee plus one time $10 application fee for 4 year license
Take 12 hour qualifying class & pass exam
Unless application made by June 1
Have installed 10 or more
homes personally

14. Renewal
Renewal requires 12 hours of continuing education over the 4 year period
Also must not have been found responsible for breaking the rule or defrauding a customer

15. Wisconsin Installation Standard
Act 45 authorized Commerce to adopt standard
Manufactured Housing Code Council - recommended rule adopted draft federal rule
Council is attached to the Dept of Commerce
Published in Administrative Register

16. Comm 21.40 Formerly Comm 27.18 Now a part of the UDC
Applies to homes built before April 1, 2007

17. Comm 21.40
No footing on unprepared fill. All organic matter must be removed.
Soil bearing test using pocket penetrometer
Grade site to drain water away for minimum of 5 ft from home
A footing for every pier, nominal 16” by 16”
Consult others if soil is less than 2000 psi

18. Comm Footings
A. one 4 by 16 by 16 solid blocks or two 4 by 8 by 16 solid blocks.
B. 16 by 16 ABS pad rated at not less than 6000 lbs
C. 18 inch diameter hole bored below the frost line or to unfractured bedrock and filled with poured concrete
D. Other materials or systems approved by Commerce

19. Comm Piers
Concrete blocks, manufactured steel stands or manufactured concrete stands
Single stack piers limited to 36 inches
Single stack piers loads limited to 8,000 lbs
36 to 80 inch piers – double blocked (layered in opposing layers)
80 inch or more – double blocked laid in concrete mortar, cores filled with mortar and ½ inch steel reinforcing rod

20. Comm 21.40 Concrete Blocks 2 core design, construction grade 8x8x16
Cores placed with cores open vertically
Block nearest main frame shall be perpendicular to the linear direction of frame
No block may contact the frame

21. Comm 21.40 – Pier Spacing No more than 7 feet on center
No more than 3 feet from exterior side of each end wall
Can be varied to follow manufacturer tables
Piers under clear-span openings of 4 feet or more in mating walls
Piers must be plumb and centered under point of support

22. Comm Caps
Solid concrete block or solid wood block having nominal thickness of at least 2 inches
Cap must be same width and length as top of pier
No more than 2 pieces – 2 piece caps positioned with joint perpendicular to frame if used

23. Comm Shims
Where used, driven from opposing sides and be no less than 4” by 8”
Wood caps and shims at least equal to #2 spruce pine fir with min bending stress rating of 1200 psi. All wood caps must be of same species of wood. All shims must be of same species of wood.

24. Comm – Height limits
Combination of nominal 2 inch solid concrete block or wood cap plus shims must not exceed 3 ½ inches
Minimum clearance under home of 12 inches between lowest point of main frame in area of utility connections. Min clearance of 12 inches for 75% of home. Remainder may be less than 12 inches but cannot touch ground

25. Federal Installation Standard
MHCC recommended rule
HUD Secretary published rule for comment
HUD Secretary published proposed final rule
OMB Review completed
Awaiting final publication (November??)

26. The Standards 3280 – HUD Construction Standards for the home
3285 – HUD Model Installation Standards
VERY IMPORTANT (means will be on test)
The following must be AT LEAST AS STRINGENT as the federal model
State Standards
Manufacturer Manuals

27. HUD Code Development
Manufactured Home Consensus Committee approves standards
Secretary of HUD submits for public comment
Secretary of HUD issues final rule following OMB input (White House)
Rule is published in Federal Register

28. Understanding Part 3285
Use the Blue and Red Cheat Sheet

29. Definitions Words have meaning so read them carefully – see 3285.5
A manufacturer must provide with each new home a DAPIA approved designs and instructions that are consistent with the standards –
DAPIA – means Design Approval Primary Inspection Agency

30. Variations by Installer
If you vary support and anchorage from the manufacturer’s instructions, the installer must obtain site-specific instructions from the (1) manufacturer or (2) a registered professional engineer or (3) registered architect (b)

31. Temporary Storage
The manufacturer’s instructions must provide at least one method for temporarily supporting each section to prevent structural damage when those sections are sited at the plant, retailer’s lot or home site (c)

32. Reference publications
Some to remember
ASTM – American Society for Testing & Materials
NFPA – National Fire Protection Assn
FEMA – Federal Emergency Management Agency

33. Application
These standards apply to HUD Code manufactured Homes not modulars.

34. Fire Separation
Fire separation distances in accord with NFPA 501(a) must be maintained. Means 10 feet
Fire separation distance must also comply with Comm 26 in a mobile home park (10 feet between basic structures)
Local ordinances might have additional requirements

35. Flood Zones
Installer is responsible to determine if home is being installed in flood zone (c)
If it is, special installation methods are required.
Also note Shoreland zoning implications

36. Zone Maps 3 maps in the HUD Code Wind – Wisconsin in Zone 1
Roof Load – Wisconsin is South and Middle Zones
Thermal Zone – Wisconsin is Zone 3
U/O value must be less than 0.079
U/O is inverse of R value = R 12.6
Homes may not be installed in a wind zone that exceeds the design load for the home.

37. Site Preparation Soil Mechanics
Soil tests can be conducted with a pocket penetrometer
Footings must be sized and spaced according to soil bearing capacity
Also see the tables in
Poor soils – peat, organic clays or uncompacted fill require a geologist, engineer or architect’s opinion

38. Site Drainage
Drainage must provided to direct surface water away from home and prevent build up under home.
Minimum slope of ½ inch per foot for the first 10 feet
Where site is sloped, home must be protected from surface runoff

39. Crown and Grade Site

41. Gutters and Downspouts
Manufacturer must specific if the home is designed for them
When installed, runoff must be directed away from the home

42. Ground Moisture Control
Vapor barrier must be installed except in arid regions
Min. 6 mill poly or equivalent
Overlap 12 inches and seal
Barrier may be under, over or around footings
Voids and tears must be repaired

43. Ground Moisture Control
1 pint of water vapor is generated in 24 hours
@ 55 degrees under 10 sq. ft of floor area sq ft home then equals 150 pints of water. That’s gallons of water

44. Foundations - Piers
Concrete blocks – Must conform to ASTM standard C 90-02
Pressure treated wood – think pilings
Adjustable metal - Manufactured piers must be labeled or listed for loads and installed to the pier manufacturer’s instructions
Listed means approved for use

45. Pier loads Must be designed with load taken into consideration
Spacing is dependant on factors such as soil bearing capacity and foot size
See tables at
Pier spacing tables do not taken into consideration flood or seismic loads see an engineer or architect

46. Pier Configuration Load bearing blocks not decorative
Nominal 8 by 8 by 16 inches
Stacked with hollow cores aligned vertically
When stacked side by side, each layer at right angles to preceding one
Center beam/mating line supports are always required for multi-section homes

50. Caps Must evenly distribute loads across the capped hollow block piers
May be made of solid concrete or masonry at least 4 inches nominal thickness OR hardwood lumber at least 2 inches thick OR corrosion protected min ½ inch thick steel or other listed materials

52. Caps Must be same length and width as piers
Split caps on double stacked piers must be installed with long dimension across the joint in blocks below

53. Gaps Must be filled with one of these methods
Nominal 4 by 6 by 1 inch shims
Must be used in pairs
Driven tightly
Must not occupy more than 1 inch of vertical space

54. Manufactured Piers
Adjustable risers must not extend more than 2 inches when finally positioned

56. Clearance under Home
Minimum of 12 inches between lowest member of main frame and grade under all areas of the home
Comm for older homes is A minimum clearance of 12 inches shall be maintained beneath the lowest point of the main frame in the area of any utility connection. A minimum clearance of 12 inches shall also be maintained under the home for at least 75% of the home. The remainder of the home may be less than 12 inches above the ground but may not touch the ground.

57. Less than 36” Piers
Permitted to constructed of open or closed cell 8 by 8 by 16 when capacity of block is not exceeded
Long sides are at right angles to supported I-beam
Hollow cores stacked vertically and at right angles to the footings
Horizontal offsets from top to bottom not to exceed ½ inch
No mortar unless instructions require

60. Piers 36 to 67” and Corner Piers
All frame piers 36 to 67” high and all corner piers over 3 block high must be double blocked
No mortar unless instructions require
Horizontal offsets not to exceed 1”

64. Piers over 67”
Must be designed by registered professional engineer or registered architect
Mortar not required unless specified

65. Perimeter support piers
Piers at mate-line supports, perimeter piers, and piers at exterior wall openings can be single open-cell or closed cell blocks to a maximum height of 54 inches
Must be installed with the long dimension parallel to perimeter rail

66. Pier Support Locations
No more than 24 inches from both ends of frame
No more than 120 inches center to center under the main I beam
Mating line, marriage wall line, ridge beam all mean the point where sections join and they require support – Be alert to extreme weight considerations in these locations!

67. Perimeter Support Locations
Both sides of any exterior door
Any side wall opening of 48 inches or more
Under any load-bearing porch posts, factory installed fireplaces and wood stoves

68. Alternative to Perimeter Supports
If additional floor joists or outriggers are providing perimeter support, the sizing of piers and footers under the main chassis beam must be adjusted.

69. Footings
Must be located on undisturbed soil or fill compacted to 90% of maximum relative density
A footing for every pier
Footing size depends on the load bearing capacity of soil, footings and piers 69

70. Footing Types Concrete types
4 inch nominal pre-cast pads meeting ASTM C with 28 day compressive strength of 1,200 psi
6-inch minimum poured in place concrete pads, slabs or ribbons with at least 28 day compressive strength of 3,000 psi 70

71. Footing Types Pressure-treated wood
Minimum 2 layers of nominal 2 inch thick pressure treated wood
Single layer of nominal ¾ inch pressure treated plywood with a max size of 16 by 16 (must be rated exposure 1 or exterior sheathing PS-1-95 rated
Cut ends must be field treated

72. Footing Types ABS footing pads
Installed according to pad manufacturer instructions and certified for use in soil classification at the site
Must be listed for required load capacity

74. Frost Protection Frost line is 48 inches statewide as set by Commerce
Footings must be designed using methods and practices that prevent the effects of frost heave by:
Conventional below the frost line footing
Monolithic slab above frost line – must be designed by registered engineer or architect
Insulated foundation system above frost line - must be designed by registered engineer or architect
Frost line is 48 inches statewide as set by Commerce

77. Footing Sizing Table How to use the tables
Use soil bearing capacity to determine size and thickness needed

78. Anchorage
After blocking and leveling, the manufactured home must be secured against the wind by an anchoring system
Anchoring equipment means ties, straps, cables, turnbuckles, chains and other approved components including tensioning devices that are used to secure a manufactured home to anchor assemblies.
Conventional anchors or alternative foundation system (Tie Down or Oliver Technologies type systems)

79. Tie Down Engineering Vector System

80. Vector System with Longitudinal Support
Note base plate and longitudinal support

81. Anchorage
The anchors must be capable of meeting the loads the home was designed to withstand – see data plate
Follow the anchor company’s instructions for spacing, angles, connections and so forth
Install anchors to their FULL depth
A diagonal anchor tie is intended to resist horizontal or shear forces, but may also resist vertical, uplift and overturning forces

82. Ground Anchors Must be listed (listed means approved)
Steel coated with zinc to not less than 0.30 oz/ft2 of surface
Capable to resist a min ultimate load of 4750 lb and a working load of 3150 lbs (check listing labels)

83. Tie Down Straps
1 ¼ inch by in or larger steel strapping conforming to ASTM D standard
Capable to resist a min ultimate load of 4750 lb and a working load of 3150 lbs (check listing labels) – Same capacity as the anchors
Coated with zinc to not less than 0.30 oz/ft2 of surface

84. Tie Downs Maximum spacing – see the tables
See drawings for near beam and second beam methods
If sidewall or over the roof, mate-line or shear wall straps are installed, they must be connected
Must be augured below the frost line unless the foundation is a frost protected above frost line system

85. Tie Down Tips No long tails
Tension evenly or you might pull the home off the supports
Determine if stabilizer plate is needed – See anchor manufacturer instructions
Try locking clamp version

86. Tie Down Safety Issues Locate Utilities
- abandoned electrical drops is a concern
- utility lineman’s gloves are recommended
- Testing for power on anchor before connecting to home can be done using a simple voltage checker
$5.25 worth of safety
Image courtesy of Lab Safety, Janesville

87. On-site structures
Each expansion room or other on-site structure must be able to support its own weight including any garage unless pre-designed by manufacturer, engineer or architect
Any addition must be designed by either the home manufacturer, a registered engineer or architect

89. Optional Equipment
Comfort systems (HVAC) must be installed by a licensed HVAC contractor if not factory installed
Air conditioning equipment must be properly sized
All heat producing equipment must be properly vented thru the skirting or exterior wall as appropriate
When not installed by home manufacturer, must be installed according to the appliance manufacturer’s instructions

91. Skirting Must be weather resistant
Attached so no water is trapped between siding and trim or forced up into the wall cavity trim it is attached to
All wood skirting within 6 inches of the ground must be pressure treated or be naturally resistant to decay and termites – This would include lumber and sheathing extension if any of the wood is less than 6 inches above the ground

96. Crawlspace Venting
NEW - One square foot for every 1,500 sq ft of floor area – Important – Check with your manufacturer before proceeding with reduced venting
Vent openings as high as practicable
Vents must located on at least two opposite sides of home
Openings must be covered with a perforated corrosion and weather resistant covering to prevent rodent entry

98. Access Opening
Not less than 18 wide by 24 high and not less than 3 sq ft
Must be located so that any utility connections under the home are accessible

100. Dryer vents, air conditioning, & combustion air vents
Must pass through skirting to the outside
This includes fireplace air inlets

101. Ductwork, Plumbing & Fuel Supplies
Manufacturer must supply instructions for proper field assembly

102. Water
When local water supply pressure exceeds 80 psi, a pressure reducing value must be installed
An identified and accessible shutoff value must be installed underneath or adjacent to the home
Crossovers and lines must be protected from freezing
Only listed for MH heat tape is permitted
Water system must be inspected and tested for leaks after completion at the site.
Disconnect water heater if test is air only

103. Piping support Water lines supported every 3 feet
Drain lines supported every 4 feet – See 48 inch on center max

104. Gas Supply
Home design calls for system pressure of 10 to 14 inches of water column pressure (0.036 psi)

105. Ductwork Crossovers All ductwork connections must be sealed
Galvanized metal straps or tape and mastics listed to UL 181 A or B must be used around duct collar and secured tightly
Metal straps required metal sheet screws
Metal ducts must be fastened with at least 3 galvanized sheet metal screws equally spaced around the collar

106. Ductwork Max distance for duct supports is 4 feet
If straps are used they must be ½” wider than spacing of spirals in flex duct
Arrange so that straps cannot slip between spirals and to prevent kinking
Cannot contact ground
Listed for exterior use only
Crossovers outside the envelop must be insulated with proper materials
In-floor or ceiling crossover connections must be sealed to prevent air leakage

107. Subpart H - Electrical
Snap connections may or must be fastened to adjacent stud – CHECK instructions
If a fixture is mounted on a combustible surface a limited combustible or non-combustible ring must be installed
Wires connected black to black, white to white and ground to ground
Test all connections

108. Smoke Alarms
Additional shipped loose alarms for basement set models are typically provided by the manufacturer
They may be wired to communicate with factory installed units at main floor

109. Exterior close-up
Manufacturers provide instructions for joining sections. Pay particular attention to directions on fasteners
The mate-line gasket must be installed following manufacturer instructions
Exterior close up strips are trim that must be fastened securely and sealed with an exterior sealant

110. Before Sections are Secured
The poly sheeting used for transport must be removed completely

111. Hinged roofs and eaves
May be subject to alternative construction inspections if flue penetrations are above the hinge

112. Gaps
UPON COMPLETION – no gaps are permitted between structural elements
PRIOR TO COMPLETION – minor gaps not exceeding one inch are permitted PROVIDED they are filed upon completion
Fill gaps must be shimmed with dimensional lumber and fastener lengths used to make connections must be increased to provide adequate penetration into receiving lumber.
Pay particular attention to end wall and floor completion gaps – May have marriage wall sheathing in from end wall ends

113. Close up
All shipping blocking, strapping or bracing must be removed from appliances, window and doors.
At a minimum, shipped loose wall panels must be installed using PVA adhesive on all framing members and fastened with 1 inch long staples or nails 6 inch on center panel edges and 12 inches on center in the field unless manufacturer directs other methods

114. Bottom Board
Bottom Board is an industry term for barrier installed by the factory on the bottom of the floor system. It is for rodent control.
Inspect for loosing or areas damaged by transport or installation
Tears must be repaired
Any missing insulation must be replaced
Splits or tears must be resealed with tape or patches
P traps must be checked to be sure they are well insulated and covered
All repaired edges must be taped or otherwise sealed

115. Access to site
The installer is responsible to ensure that transportation routing is possible and permits obtained
Effective 4/01/07 disturbed soil areas of 1 acre or more at property site are subject to permits and UDC erosion control regulations
(This also includes entire driveway areas!)

116. Gas appliances Make sure orifices match the fuel supply
Inspect vents to make sure they were not damaged in transit

117. Other UDC Issues to Watch
Site constructed elements subject to UDC
Basement stairs
Exterior decks, stairs and railings
Garage attachments
Habitable basements
Egress windows for bedrooms
Heating calculations for entire envelop

118. Trouble spots-Basement Stairs
Finished Stairwell Length (FSL)
Headroom
(Min. 6'-4")
Headroom + Floor/Ceiling Depth (HFCD) Finished Stairwell Length(FSL)
Unit Rise Unit Run
So to solve for FSL, FSL = Unit Run x HFCD
Unit Rise
Floor/Ceiling Depth
Max. 8"
Unit Run
Min. 9"
Two Similar Right Triangles
Maintain 6'-4" Headroom In Required 3' Long Landing

125. “Structural Analysis” per Dept. of Comm.
Comm (Definitions.)
 (73) “Structural Analysis” is a branch of the physical sciences which uses the principles of mechanics in analyzing the impacts of loads and forces and their effect on the physical properties of materials in the form of internal stress and strain.
 Comm (Structural Analysis Standards.)
 Structural analysis shall conform to the following nationally recognized standards.
 ( c ) Concrete. Plain, reinforced or pre-stressed concrete construction shall conform to the following standards:
 ·        1. ACI Standard 318, “Building Code Requirements for Reinforced Concrete”.
·        2. ACI Standard 318.1, “Building Code Requirements for Structural Plain Concrete”.
  Comm (Frost Penetration.)
 ·        (2) Exceptions. (a) Floating slabs constructed on grade need not be installed below the minimum frost penetration line provided measures have been taken to prevent frost forces from damaging the structure.
·        Also, ( c ) Stoops or ramps need not be installed below the minimum frost penetration level provided measures are taken to prevent frost forces from damaging the structure.

126. Class Verification Certificate
Continuing Education = 8425
Password is ……
If password is not on the form it won’t be processed by the state.