Code of Maine Rules › 02 - DEPARTMENT OF PROFESSIONAL AND FINANCIAL REGULATION › 385 - MANUFACTURED HOUSING BOARD › Chapter 890 - MANUFACTURED HOME INSTALLATION STANDARDS › Subchapter D - FOUNDATIONS › Section 385-890-D-X - Pier Location and Spacing

Current through 2024-29, July 17, 2024
A. The location
				  and spacing of piers depends upon the dimensions of the home, the live and dead
				  loads, the type of construction (single-or multi-section), I-beam size, soil
				  bearing capacity, footing size, and such other factors as the location of doors
				  or other openings.
B. Mate-line and
				  column pier supports must be in accordance with this subchapter and consistent
				  with Figures A through C of this section unless the pier support and footing
				  configuration is designed by a registered professional engineer or registered
				  architect.
C. Piers supporting the
				  frame must be no more than 24 inches from both ends and not more than 120
				  inches center to center under the main rails.
D. Pier support locations and spacing must be
				  presented to be consistent with Figures A and B to Subchapter D, Section
				  XII, as applicable, unless
				  alternative designs are provided by a registered professional engineer or
				  registered architect in accordance with acceptable engineering practice.
Figure A to Subchapter D, Section X - Pier Location
					 and Spacing:
Typical Mate-Line Column Pier and Mating Wall Support
When Frame Only Blocking is Required
Click
					 here to view Image
Footings sized for single spans C and D to support
								the Pier and Footing Load indicated in Table 3 to Subchapter D, Section
								III. [Note:If wall is less than
								16" in width use combined span C+D, single pier.]
Footing sized for span B or C, as applicable, to
								support the Pier and Footing Load indicated in Table 3 to Subchapter D, Section
								III.
Footings sized for combined spans A+B to support
								the Pier and Footing Load indicated in Table 3 to Subchapter D, Section
								III(D).
Footing sized for span A to support the Pier and
								Footing Load indicated in Table 3 to Subchapter D, Section
								III(D).
Notes to Figure A:
1. Bottom of footings must extend below frost
				  line depth, unless designed for placement above the frost lines. (See
				  Subchapter D, Section
				  XII(B)
				  ).
2. Piers may be offset up to 6
				  inches in either direction along the supported members to allow for plumbing,
				  electrical, mechanical, equipment, crawlspace, or other devices.
3. Single-stack concrete block pier loads
				  must not exceed 8,000 lbs.
4.
				  Prefabricated piers must not exceed their approved or listed maximum vertical
				  or horizontal design loads.
5. When
				  a full-height mating wall does not support the ridge beam, this area is
				  considered an unsupported span - Span B.
6. Piers are not required at openings in the
				  mating wall that are less than 48 inches in width. Place piers on both sides of
				  mating wall openings that are 48 inches or greater in width. For roof loads of
				  40 psf or greater, a professional engineer or registered architect must
				  determine the maximum mating wall opening permitted without pier or other
				  supports.
Figure B to Subchapter D, Section X - Pier Location
					 & Spacing:
Typical Mate-Line Column Pier and Mating Wall
					 Support
When Perimeter Blocking is Required
Click
					 here to view Image
See Note 1
Footing sized & spaced to support the Load
								indicated in Table 2 to Subchapter D, Section
								III(D).
Footing sized for span C to support the Load
								indicated in Table 2 to Subchapter D, Section
								III(D).
Footing sized & spaced to support the Load
								indicated in Table 2 to Subchapter D, Section
								III(D).
Footing sized for span B to support the Pier &
								Footing Load indicated in Table 3to Subchapter D, Section
								III(D).
Footing sized for combinedspan A+B to support the
								Pier &Footing Load indicated in Table 3 to Subchapter D, Section
								III(D).
See Note 6
Footing sized for span A to support the Pier
								&Footing Load indicated in Table 3 to Subchapter D, Section
								III(D).
Notes to Figure B:
1. Bottom of footings must be below the frost
				  line depth, unless designed for placement above the frost line. (See Subchapter
				  D,
Section
					 XII(B) ).
2. Piers may be offset 6 inches in
				  either direction along supported members to allow for plumbing, electrical,
				  mechanical equipment, crawlspace, or other devices.
3. Single stack concrete blocks pier loads
				  must not exceed 8,000 lbs.
4. Piers
				  are not required at openings in the mating wall that are less than 48 inches in
				  width. Place piers on both sides of mating wall openings that are 48 inches or
				  greater in width. For roof loads of 40 psf or greater, a professional engineer
				  or registered architect must determine the maximum mating wall opening
				  permitted without pier or other supports.
5. When a full-height mating wall does not
				  support the ridge beam, this area is considered an unsupported span - Span
				  B.
6. In areas where the open span
				  is greater than 10 ft., intermediate piers and footings must be placed at
				  maximum 10 ft. on center.
7.
				  Prefabricated piers must not exceed their approved or listed maximum horizontal
				  or vertical design loads.
8. Column
				  piers are in addition to piers required under full-height mating
				  walls.
Figure C to Subchapter D, Section X - Pier Location
					 & Spacing:
Typical Mate-Line Column and Piers
Notes to Figure C:
Click
					 here to view Image
1.
				  Mate-line column supports piers are installed with the long dimension
of the concrete block perpendicular to the rim
					 joists.
2. Pier and footing
				  designed to support both floor sections. Loads as listed in Table 3 to
				  Subchapter D, Section
				  III are total column loads for
				  both sections.