Chapter 15.32
MANUFACTURED HOME AND COMMERCIAL COACH INSTALLATION
Sections:
15.32.020 Occupancy restrictions and compliance.
15.32.025 Manufactured homes—Prerequisites to water service.
15.32.030 Installation requirements—General.
15.32.040 Building site preparation.
15.32.050 Foundation system footings.
15.32.070 Foundation system piers.
15.32.090 Foundation fascia/skirting.
15.32.100 Plumbing and mechanical.
15.32.110 Placement on site—Address.
15.32.130 Auxiliary structures and alterations.
15.32.140 Certified installer tag, inspections, final inspection and occupancy.
15.32.150 Manufactured home transport permit.
15.32.010 Purpose.
The purpose of this chapter is to establish minimum standards for the placement and installation of manufactured homes and commercial coaches. For the purposes of this chapter, the term “manufactured home” shall apply to both manufactured homes and commercial coaches. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.020 Occupancy restrictions and compliance.
Every manufactured home shall be placed, installed, stored, and occupied in pursuant to a manufactured home installation permit issued under this chapter and all applicable provisions of Chapter 296-150M WAC, Chapter 43.63B RCW, “Mobile and Manufactured Home Installation,” and the Housing and Urban Development Code (HUD), Part 3280, of the federal regulations, Manufactured Home Construction and Safety Standards (MHCSS). The manufactured home shall not be occupied until all setup procedures are completed and approved in accordance with this chapter and the manufactured home is approved for occupancy. A dealer may not deliver a manufactured home to a site for installation until the dealer has verified that the owner or installer has obtained an installation permit for the manufactured home. (Statutory Authority: RCW 43.22.350 and 43.22.440. 83-01-018 (Order 82-37), 296-150B-205, filed 12/6/82. Statutory Authority: RCW 43.22.440. 82-09-059 (Order 82-12), 296-150B-205, filed 4/19/82.) (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.025 Manufactured homes—Prerequisites to water service.
No approved domestic water purveyor shall provide water to any manufactured home until installation of such manufactured home has been approved and occupancy approved in accordance with this chapter. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.030 Installation requirements—General.
A. All manufactured homes shall be installed in compliance with the National Manufactured Housing Procedural and Enforcement Regulations in subparts F and I of 24 CFR Part 3282, which are incorporated into this chapter by this reference.
B. A HUD-labeled manufactured home shall also be installed in compliance with the manufactured home manufacturer’s installation instructions. The instructions must be approved by HUD. The manufacturer shall send two copies of its approved installation instructions to the purchaser of the manufactured home. The copies shall be in the home and available at the time of inspection. A manufactured home not labeled by HUD may also be installed in accordance with installation instructions provided by a professional engineer or architect licensed in Washington.
C. To the extent that the installation of a manufactured home is not covered by a manufacturer’s, engineer’s or architect’s instructions, the manufactured home shall comply with the installation requirements set out in WAC 296-150M-0600 through 296-150M-0670.
D. ANSI Standard A225.1 shall apply for relocated homes when the manufacturer’s set-up manual is not available.
E. Pre-HUD-Code homes built prior to the MHCSS, 24 CFR 3280, or other manufactured homes that have been altered or are in disrepair, are subject to a fire and life safety inspection conducted by the Washington State Department of Labor and Industries, prior to installation permit issuance.
F. No person, firm, partnership, corporation or other entity may install a manufactured home unless he, she or it owns the manufactured home, is a licensed mobile home dealer, a certified manufactured home installer registered under Chapter 43.63B RCW, or is a contractor registered under Chapter 18.27 RCW. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.040 Building site preparation.
A manufactured home may be installed at a building site only upon the following conditions for site preparation:
A. The ground at the site has been properly graded to allow water to drain away from the home. The minimum slope shall be one-half inch per foot for at least five feet in all directions away from the home.
B. The ground has adequate compaction and load-bearing capacity to meet the requirements listed in the manufacturer’s installation manual. If all or part of the ground at the site intended to support the manufactured home or other structures appears to contain nonengineered fill material, expansive soils, ground water, and detrimental amounts of organic or deleterious material, the building official may require a soils engineering report to verify adequate compaction and load bearing ability to meet the support requirements specified by the home manufacturer. The soils engineering report, including recommendations, shall be prepared, stamped and signed by a professional engineer, licensed by the State of Washington to prepare such a report.
C. Vegetation and organic matter, including all stumps and roots, shall be removed from the soil to a depth of least of twelve inches below the final surface grade of the ground in the area to be occupied by the manufactured home.
D. The site’s foundation base shall be free of frost and frozen ground at the time the foundation system footings are installed. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.050 Foundation system footings.
A. Foundations, including concrete runners and pads, shall be designed and/or installed according to the manufacturer’s installation manual. In the event that the manufacturer has not provided a foundation design in the installation manual, the foundation design shall be designed by an engineer or architect. Relocated homes may use ANSI Standard A225.1, if there are no manufacturer’s instructions.
B. The top of the foundation (concrete runner or pad) shall be at least eighteen inches below finish grade. For nonrecessed (nonpit-set) manufactured homes, the bottom of all required perimeter blocking/foundation must be placed greater than eighteen inches below finish grade. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.060 Crawl space height.
The crawl space height shall be at least eighteen inches between the I-beams and the ground or I-beams and the top of the foundation (concrete runner or pad); whichever is less, over at least seventy-five percent of the crawl space area. At no point under the home may clearance be less than twelve inches. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.070 Foundation system piers.
Pier supports, including hollow-core concrete blocks or metal engineered adjustable stands, shall be installed according to the manufacturer’s installation manual. In the event that the manufacturer’s instructions do not cover an aspect of installation, specific instructions from the manufacturer or from an engineer or architect shall be provided. Relocated homes may use ANSI Standard A225.1 if there are no manufacturer’s instructions. Metal stands used as piers must have the manufacturer’s name, model number, testing lab, and rated capacity stamped on them. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.080 Anchoring systems.
All manufactured homes must be anchored according to the manufacturer’s installation instructions. In the event there are no manufacturer’s instructions for anchoring into concrete runners, anchors shall be installed according to the design of an engineer or architect. Anchoring equipment designed and certified by an engineer that is provided with instructions and the appropriate documentation is acceptable. Engineered anchoring equipment must be installed in accordance with the home manufacturer’s overall anchoring instructions. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.090 Foundation fascia/skirting.
A. Every manufactured home shall have an approved foundation fascia around its entire perimeter.
B. Wooden foundation skirting systems recessed or within six inches of finish grade shall use only preservative-treated lumber and plywood. The preservative-treated wood system shall be marked by an approved inspection agency certified to inspect preservative-treated lumber. The plywood shall be APA rated sheathing and note: FOUNDATION TREATING GRADE. The wooden stud framing system supporting the sheathing shall be framed in a conventional method and have a minimum two-inch-by-four-inch top and bottom pressure-treated plate and minimum two-inch-by-four-inch pressure-treated studs placed a maximum of two feet on center.
C. Skirting set more than six inches above finish grade shall be of durable materials suitable for exterior exposures.
D. All metal fasteners shall be galvanized, stainless steel, or other corrosion-resistant material. Holes or gaps may not exceed one-quarter inch.
E. Concrete and concrete masonry unit (CMU) exterior footings and foundations, when required, shall be reinforced. Footings shall have at least two continuous number four, one-half-inch horizontally placed reinforcement bars evenly spaced and supported. Foundations shall have at least one continuous number four reinforcement bar suspended horizontally six inches from the top of the foundation and vertical number four reinforcement bars embedded three inches into the footing and spaced four feet on center and tied to the continuous horizontal reinforcement bar. The horizontal bars shall overlap a minimum fifteen inches.
F. A six-mil thick, black polyethylene plastic ground cover/vapor barrier is required. The ground cover/vapor barrier shall be placed over footings and under support piers. Pieces shall overlap a minimum of twelve inches and be secured. If the ground cover/vapor barrier is left temporarily exposed to the wind prior to skirting, it shall be satisfactorily fastened to the ground.
G. Foundation ventilation shall be provided according to the manufacturer’s installation manual. If there is no installation manual, ventilation shall be provided in the crawl space at a minimum of one square foot of net free venting area for every one hundred fifty square feet (one to one hundred fifty) of the home’s floor area. Net free venting area is calculated by deducting the area of the louvered vent cover from the actual vent opening. Ventilation openings shall be placed evenly, within three feet of each corner of the home, and as high as possible. Openings shall be located to provide cross-ventilation on at least two opposite sides. Vents shall be covered with corrosion-resistant wire mesh with mesh openings of one-quarter inch in dimension. The net free venting area may be reduced to one to one thousand five hundred when moisture is nominal; the required ground cover is installed; adequate cross-ventilation has been provided; and vent openings are placed within three feet of each corner.
H. WAC 296-150M-610(5) requires a minimum of one crawl space access door measuring at least eighteen inches by twenty-four inches. Access doors shall not be placed where blocking piers, metal or wood framing supports, mechanical and plumbing equipment, are within any portion of the access opening. All areas under the home must be available for inspection. Valves or control devices, such as water shutoff valves or waste line cleanouts, must be accessible within twenty feet of the crawl space entrance. When homes/coaches exceed two sections, more than one access door may be required. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.100 Plumbing and mechanical.
A. Water heater relief valve drains shall extend past the exterior of the skirting and be directed downward. The drainpipe shall elbow down, and terminate between six and twenty-four inches aboveground. Any water from the drainpipe shall be prevented from re-entering the crawl space. The drain line may not be trapped and must slope down continuously to the exterior of the skirting. Terminal fittings are not permitted.
B. Condensate drains shall be piped past the outside of the skirting or exterior wall, and drain away from the home.
C. Clothes dryer exhaust vents must extend to the outside of the skirting with no dips or sags, and shall be equipped with a back-draft damper at the terminal end. Ducts shall not be connected or installed with sheet metal screws or other fasteners that will obstruct the flow. The minimum duct diameter is four inches. The duct shall be metal and shall have a smooth interior surface.
D. Horizontal drainage waste lines are to be installed according to the Uniform Plumbing Code as incorporated by HUD. Waste lines shall be sloped at least one-quarter inch per foot. Waste lines shall be properly supported not more than four feet on center. A cleanout is required on the upper terminal end of the visible main trunk line or an approved two-way cleanout may be installed inside the skirting wall at the lower end of the drain line or installed outside the skirting near the connection between the building drain line and the building sewer line. Additional cleanouts are required for each change of direction if the total aggregate change exceeds one hundred thirty-five degrees. Branch lines greater than five feet in length require cleanouts above the floor or in the crawl space. Branch lines servicing sinks require cleanouts regardless of the length. Cleanouts shall have sufficient clearance space for access and use. Cleanouts on piping two inches or less in diameter require not less than twelve inches of clearance. Cleanouts on piping larger than two inches in diameter require at least eighteen inches of clearance. Plastic drain line pipe located in the crawl space area shall be DWV rated and UPC approved, Schedule 40 ABS DWV, or Schedule 40 PVC DWV. The building waste line and the sewer line connection shall be a minimum of two feet from the exterior side of the skirting. Sewer (UPC Schedule 40, “green plastic pipe”) pipe is not permitted inside the crawl space.
E. The water supply connection shall be installed according to the manufacturer’s set-up manual. Water supply piping shall be UPC approved. If water supply pressure exceeds eighty pounds per square inch, an approved pressure-reducing valve must be installed in the supply pipe. A main shutoff valve must be installed in the supply piping prior to the connection to the home. The valve must be of the full-flow type such as a gate valve or ball valve. It must be at least three-quarters-inch nominal diameter or the same size as the supply pipe, whichever is greater. The water supply pipe entering the crawl space must be fully covered with pipe insulation to a value of R-3. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.110 Placement on site—Address.
A. Each manufactured home shall be placed on the parcel according to the plot plan described on the permit.
B. For the purpose of emergency response, a street address shall be assigned and conspicuously posted so as to be visible from the public road or right-of-way serving the parcel. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.120 Landings and steps.
Manufactured homes shall have a landing on the exterior side of each exit door. Landings shall be a minimum of thirty-six inches by thirty-six inches in size, or at least the width of the exit door served if the door is greater than thirty-six inches in width. Landings exceeding thirty inches in height require a guardrail. Riser height for stair steps is a maximum seven and three-quarter inches. Stair treads must be a minimum ten-inch run. Steps shall be a minimum of thirty-six inches in width and steps with four or more risers require a handrail, as required by the International Building Code. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.130 Auxiliary structures and alterations.
A. Attached or detached auxiliary structures such as site-built residential additions, garages, uncovered decks over thirty inches in height, covered decks regardless of height, porch covers, covered patios, basements, and carports, require a separate building permit in addition to the manufactured home installation permit.
B. Site-built additions that affect the structure or mechanical equipment of the manufactured home, such as heating or cooling systems, elimination or installation of windows, sliding glass doors, air conditioners, and gas or solid fuel heating appliances, are considered alterations. Alterations must be reviewed, permitted, inspected and approved by the Washington State Department of Labor and Industries.
C. Self-supporting, site-built auxiliary structures attached to the home require a separate permit and must be reviewed, approved and inspected by the building official. Structures partially supported by the manufactured home require a separate alteration permit from the Washington State Department of Labor and Industries as well as a permit from Douglas County. To be considered self-supported, auxiliary structures must have an independent foundation system around the entire perimeter, in addition to other applicable requirements of this title.
D. Placement of a manufactured home over a basement must be planned and designed by an engineer or architect and reviewed, approved and inspected by the building official. Special design consideration must be given to: attachment of the home to the foundation; interior structural support; stairwell access to the lower level, and height of basement walls to allow for proper headroom height in stairwell. Basement excavation and installation requires separate permits from the building official. Field alterations to the home must be approved by the Washington State Department of Labor and Industries.
E. Garage attachments to manufactured homes require a fire protection separation wall per the International Codes. The separation may be attained by the installation of materials approved for one-hour fire-resistive construction [one layer of five-eighths-inch, fire-rated gypsum board] on the garage side and a self-closing, tight-fitting solid wood door one and three-eighths inches in thickness, or a self-closing, tight-fitting metal door having a labeled fire-protection rating of not less than twenty minutes. Garage attachments require a separate permit from the building official. (Res. TLS 06-13 § 1 (part); Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.140 Certified installer tag, inspections, final inspection and occupancy.
A. The combined inspection record card/installer tag issued, together with the installation permit, must be posted at the site prior to any site work, foundation work, and inspections performed by the building official. Care must be taken to protect and secure the inspection record card/installer tag at the site. If the inspection card/tag is not posted, is lost, or is damaged beyond use, a new card must be issued, and a fee for reissuing the card may be required. If a property owner does the work listed on the tag, the property owner must write “owner” on the appropriate line and sign the tag. The building official shall not approve installation inspections until the certified installer performing the installation work, or the property owner, has put their current certification number and signature on the installer tag indicating the work performed. (RCW 43.63B.060(8))
B. The manufactured home must not be skirted or framed for skirting until after the blocking, tie downs and plumbing have been approved. The manufactured home must be unlocked and accessible in order to verify data plate information located inside the home. The manufacturer’s set-up manual shall be located between the I-beam and the bottom board within five feet of the main electrical feeder. When a concrete foundation has been installed, the set-up manual shall be located between the I-beam and the bottom board within five feet of the access opening or adjacent to the data plate inside the home. Each manufactured home approved for placement shall be subject to the following inspections prior to occupancy:
1. Siting to verify zoning and land conditions.
2. Footings and foundation.
3. Data plate verification, piers/blocking, tie-downs/anchorage, and plumbing, prior to skirting.
4. Skirting, landings, steps, ventilation, and crawl space access.
5. Grading and final occupancy.
C. The owner shall be responsible for arranging for inspections. The owner, or the owner’s representative, shall notify the building official when the work is ready for inspection and request that an inspection be conducted. A request for inspection shall be made at least one business day prior to the date inspection is desired. Inspections shall be scheduled by the building official based upon workload and the location of inspection sites. It shall be the duty of the owner to provide access to the work and a means for inspection. Work scheduled for inspection shall be complete and ready for inspection when the building official arrives at the site. In the event that the work is not ready for inspection, or the installer tag has not been signed, or the set-up manual is not provided, or the home is not accessible, then a re-inspection fee shall be assessed. Follow-up inspections shall not be performed until the re-inspection fee is paid.
D. The manufactured home shall not be approved for occupancy until all necessary inspections, including the final inspection, have been completed, signed-off and approved by the certified installer and the building official. Other necessary approvals required prior to occupancy may include: alterations to the home, approved by Washington State Department of Labor and Industries, and required auxiliary structures, approved by the Douglas County Land Services Division. If the permit is conditioned upon construction of a garage, the garage must be constructed, complete and have passed all necessary inspections prior to occupancy. Occupying the home prior to approval of final occupancy shall subject the permit holder and/or owner to penalties and enforcement action, including cessation of water service. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))
15.32.150 Manufactured home transport permit.
Manufactured home transport permits shall be subject to the county’s adopted Washington Model Traffic Ordinance. The permit shall be clearly displayed in the lower right-hand corner of the lead vehicle’s windshield while moving the manufactured home on any county roadway. (Res. TLS 04-41 Exh. A (part): Ord. TLS 01-02-06B Exh. A (part))