Exam Cheat Sheet · Quick Reference

Idaho Manufactured Housing Retailer

Idaho  ·  PSI Services Contractor

Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.
Total questions
50
Passing score
70%
Exam time
150 min
Administered by
PSI Services Contractor
Format
Reference materials allowed

Idaho State Portion 50 questions

Idaho Manufactured Home Installation Standard Manual 50 Q · 100%
GeneralAccessory Buildings and StructuresDefinitions and AcronymsPermits and InspectionsGeneral Installation StandardsStandard Set Installation StandardsPermanent Foundation Installation StandardsElectrical ConnectionsPlumbing ConnectionsMechanical ConnectionsUnderfloors, Access and Egress

Key Distinctions

Accessory buildingvsAccessory structure

Under the definition of "Accessory Building or Structure," accessory buildings include ramadas, storage sheds and garages, while accessory structures include awnings, carports, decks, steps and ramps.

Idaho Manufactured Home Installation Standard Manual, Definitions, Item 02 (Page 62)
Installation — "Construction"vsInstallation — "Siting"

Construction is work performed inside the home after it leaves the factory (affecting arrangements/methods of construction, fire and life safety, and electrical, plumbing and mechanical systems), while siting is work performed outside the home to place it on its site, expressly including support and tie-down systems, utility connections, skirting and steps.

Idaho Manufactured Home Installation Standard Manual, Definitions, Item 32 (Page 64)
Utilities inspection items (204.03)vsInstallation inspection items (204.02)

Air conditioning, after-market electrical or plumbing equipment and mechanical equipment are utilities inspection items, whereas duct crossovers, flue/chimney/vents and dryer exhaust ducted through skirting or foundation are installation inspection items.

Idaho Manufactured Home Installation Standard Manual, Chapter 2, Subsections 204.02-204.03 (Pages 16-17)
Standard setvsFoundation set

A standard set is a home on footings and piers with the perimeter enclosed by above-ground skirting or fascia, while a foundation set is on footings and piers with the perimeter enclosed by a supporting permanent foundation footing and stem wall extending below the frost line.

Idaho Manufactured Home Installation Standard Manual, Definitions, Items 24 and 63 (Pages 63, 67)
Ground level installationvsFoundation set

A ground level installation has a below-grade foundation system with a perimeter retaining wall or foundation that has earth backfilled against it, while a foundation set is on footings and piers with a permanent foundation footing and stem wall extending below the frost line.

Idaho Manufactured Home Installation Standard Manual, Definitions, Items 24, 31 and 63 (Pages 63-66)
Stabilizing devicesvsSupport system / Foundation system / Load bearing device

Stabilizing devices covers ALL components of both the anchoring and support systems (piers, footings, foundations, ties, anchoring equipment, ground anchors), while support system is only foundations, footings, piers, caps and shims, foundation system is a perimeter footing and stem wall support, and a load bearing device is a single support component.

Idaho Manufactured Home Installation Standard Manual, Definitions, Item 62 (Page 67)
Main frame footings/piers on a permanent foundation set (503.01.c)vsMain frame footings/piers on a standard set (403.01.c)

On a permanent foundation set they are placed not more than 30 inches from the ends of the frames, while on a standard set they are placed not more than 12 inches from the ends of the frames (both then continue at 6 feet on center).

Idaho Manufactured Home Installation Standard Manual, Chapter 5, Subsection 503.01 (Page 36)
Poured-in-place pad footings, permanent foundation set (502.01.a)vsPoured-in-place pad footings, standard set (402.01.b)

Permanent foundation pads must be nominal 8 inches or thicker, while the 4-inch pad is the minimum for standard set installations.

Idaho Manufactured Home Installation Standard Manual, Chapter 5, Subsection 502.01 (Page 34)
Marriage line footings on a permanent foundation set (503.03.a)vsRidge beam support column footings on a standard-set-to-permanent conversion (504.02.d)

The entire marriage line must be supported by minimum 256 square inch poured-in-place footings and piers, while on a conversion every ridge beam support column must bear on a footing of minimum 512 square inches.

Idaho Manufactured Home Installation Standard Manual, Chapter 5, Subsection 503.03 (Page 37)
Anchoring equipment allowable working loadvsAnchoring equipment overload test value

Anchors, straps and tension devices must resist an allowable working load equal to or exceeding 3,150 lbs., and must additionally withstand a 50% overload of 4,725 lbs. without failure of the equipment or attachment point.

Idaho Manufactured Home Installation Standard Manual, Chapter 5, Section 505 (Pages 43-44)
Single stack concrete block piervsDouble stack interlocking concrete block pier

Single stack block piers are limited to loads not to exceed 5,000 pounds and double stack block piers to 16,000 pounds; double and single piers may be combined for higher loads.

Idaho Manufactured Home Installation Standard Manual, Chapter 5, Subsection 502.02 (Page 35)
1/2" x 10" anchor bolt (504.01.a(3))vs1/2" x 7" anchor bolt (504.01.c(1))

The 1/2" x 10" bolt attaches the 2x4 sill plate to a poured concrete stem wall (6 feet on center and within 12 inches of each corner), while the 1/2" x 7" bolt secures the bottom plate of a pressure treated wood stem wall to its footing.

Idaho Manufactured Home Installation Standard Manual, Chapter 5, Subsection 504.01 (Page 39)
RamadavsCarport / Awning / Porch

A ramada is a stationary roof structure extending over the manufactured home (and possibly a patio or parking space) for protection from snow, sun or rain; a carport is a roof with supports and not more than one wall for sheltering a motor vehicle, an awning likewise has not more than one wall, and a porch may have two or more walls.

Idaho Manufactured Home Installation Standard Manual, Definitions, Item 52 (Page 66)
TagvsLabeled

A tag is a label or insignia issued by the Division applied to indicate compliance with federal or state laws, rules and regulations, while "labeled" refers to the identifying mark of a nationally recognized testing laboratory or inspection agency on equipment and materials.

Idaho Manufactured Home Installation Standard Manual, Definitions, Items 34, 44 and 65 (Pages 64-67)
Placement requiring an installation permitvsPlacement not requiring an installation permit

Permits are required before installing a home on a building site or in a park, including display homes in parks, subdivisions and residential lots and homes occupied on a sales lot; permits are NOT required for unoccupied manufactured homes temporarily displayed on a sales lot or in storage.

Idaho Manufactured Home Installation Standard Manual, Chapter 2, Subsection 201.01 (Page 15)

Key Terms

Approved Idaho Manufactured Home Installation Standard Manual, Definitions, Items 04 and 17 (Pages 62-63)
Approved, licensed, or certified by the Division of Building Safety or its designee (Definition 04); "Division" means the State of Idaho Division of Building Safety (Definition 17).
Ground Level Installation Idaho Manufactured Home Installation Standard Manual, Definitions, Items 24, 31 and 63 (Pages 63-66)
A manufactured home with a below-grade foundation system and a perimeter retaining wall or foundation which has earth backfilled against it.
Foundation Set Idaho Manufactured Home Installation Standard Manual, Definitions, Items 24, 31 and 63 (Pages 63-66)
A home installed on footings and piers with the perimeter enclosed by a supporting permanent foundation footing and stem wall extending below the frost line.
Standard Set Idaho Manufactured Home Installation Standard Manual, Definitions, Items 24 and 63 (Pages 63, 67)
A manufactured home installed on footings and piers which has a perimeter enclosed by above-ground skirting or fascia.
Foundation System (Item 23) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 23, 24, 62 and 64 (Pages 63, 67)
A perimeter footing and stem wall support system.
Support System (Item 64) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 23, 24, 62 and 64 (Pages 63, 67)
The combination of foundations, footings, piers, caps and shims that supports the weight of the home.
Stabilizing Devices (Item 62) Idaho Manufactured Home Installation Standard Manual, Definitions, Item 62 (Page 67)
All components of the anchoring system and support systems — piers, footings, foundations, ties, anchoring equipment, ground anchors and other equipment which supports the home and secures it to the ground.
Load Bearing Device (Item 36) Idaho Manufactured Home Installation Standard Manual, Definitions, Item 62 (Page 67)
Equipment used in support of the home — footings, piers, caps and shims.
Tie-Down (Item 68) Idaho Manufactured Home Installation Standard Manual, Definitions, Item 62 (Page 67)
A single anchoring device.
Recessed Porch (Item 53) Idaho Manufactured Home Installation Standard Manual, Definitions, Item 53 (Page 66)
An open floor area supported by the main frame which is located outside the exterior walls of the manufactured home.
Ramada (Item 52) Idaho Manufactured Home Installation Standard Manual, Definitions, Item 52 (Page 66)
A stationary structure having a roof extending over a manufactured home, which may also extend over a patio or parking space, used principally for protection from snow, sun or rain.
Carport (Item 12) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 07, 12 and 50 (Pages 62-66)
A stationary structure consisting of a roof with its supports and not more than one wall, used for sheltering a motor vehicle.
RME (Responsible Managing Employee) (Item 57) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 39 and 57 (Pages 65-66)
The person designated by the retailer, installer, manufacturer or resale broker to supervise other employees, either personally or through others.
Feeder Assembly (Item 21) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 21 and 58 (Pages 63, 66)
The overhead or under-chassis feeder conductors, including the grounding conductor, with necessary fittings and equipment, or an approved power supply cord, designed to deliver energy from the electrical supply source to the home's distribution panelboard.
Service Equipment, Manufactured Home (Item 58) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 21 and 58 (Pages 63, 66)
The equipment for connecting the feeder assembly; it must be readily accessible, in sight of the home, and not more than 30 feet from the exterior wall of the manufactured home (note to Section 603, citing NEC Article 550-23(a)).
Option (Item 48) Idaho Manufactured Home Installation Standard Manual, Definitions, Item 48 (Page 66)
A provision made during manufacture of a home to facilitate the future installation of an appliance or other equipment, such as an air conditioner, wet bar or dishwasher.
New Home (Item 46) Idaho Manufactured Home Installation Standard Manual, Definitions, Item 46 (Page 66)
A manufactured home that has not been titled or converted to real property and/or has not been approved for occupancy by the jurisdiction having authority to do so.
Testing Laboratory or Testing Agency (Item 66) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 17 and 66 (Pages 63, 67)
An organization that tests equipment and systems, is qualified to test to approved standards, is independent of any single manufacturer, publishes test reports, and whose methods and standards have been approved by the Division (Idaho Division of Building Safety).
Tag (Item 65) Idaho Manufactured Home Installation Standard Manual, Definitions, Items 34, 44 and 65 (Pages 64-67)
A label or insignia issued by the Division and applied to manufactured homes to indicate compliance with federal or state laws, rules and regulations.
IDAPA 07.03.12.020 Idaho Manufactured Home Installation Standard Manual, Chapter 2, Subsection 203.01 (Page 15)
The rule for which local jurisdictions that have adopted a building code (and the Division in jurisdictions that have not) issue permits and inspect all manufactured/mobile home installations to determine compliance.

Formulas to Know

Perimeter sidewall footing/pier spacing by roof load — standard set (403.02.c)30 to 40 psf → 8 ft on center max; over 40 and up to 60 psf → 6 ft on center max; over 60 and up to 80 psf → 4 ft on center max. (Example: a 50 psf roof load requires 6 ft on center.)
Marriage line rim joist support spacing with a bearing wall above — permanent foundation set (503.03.d(3))over 40 and up to 60 psf → 6 ft on center max; over 60 and up to 80 psf → 4 ft on center max; over 80 and up to 100 psf → 3 ft on center max. (Example: 75 psf with bearing wall above requires 4 ft on center.)
Marriage line rim joist support spacing with a bearing wall above — standard set (403.03.d(3))30–40 psf → 8 ft; 41–60 psf → 6 ft; 61–80 psf → 4 ft; over 80 and up to 100 psf → 3 ft on center maximum. (Example: 90 psf with bearing wall above requires 3 ft on center.)
Concrete block pier stacking by height (402.02.a)Single stack permitted up to 36 in. high under the main frame or marriage line and up to 48 in. high under perimeter walls; above those heights piers must be double stacked with interlocking blocks; no block pier over 80 in. high unless designed by an Idaho Licensed Professional Engineer (403.04 likewise caps pier height at 80 in.).
Concrete block pier load limits (402.02.a(4) / 502.02.a(4))Single stack ≤ 5,000 lb; double stack interlocking ≤ 16,000 lb; double and single piers may be combined for higher loads.
Anchoring device test load (404.04)Test to 1.5 × horizontal wind load of 15 psf, in combination with a roof uplift of 9 psf, using ASTM D-3953 test procedures.
Anchoring equipment strength — permanent foundation (505.02)Allowable working load ≥ 3,150 lb, and withstand a 50% overload (4,725 lb) without failure of the equipment or attachment point.
Site drain piping grade (704.01 / 705)1/4 in. per foot, except as otherwise permitted by the authority having jurisdiction; where a full size cleanout is installed at the upper end, grade may be reduced to 1/8 in. per foot.
Foundation vent placement (504.01.f)Vent within 3 ft of each corner and at 20 ft maximum spacing (consistent with underfloor ventilation placement of Section 902).
Tall main frame pier limit — permanent foundation (503.05)No more than 25% of main frame pier supports may exceed 36 in. in height without prior approval of the local authority having jurisdiction, unless the home is set on a basement.