Mobile Home Inspection Checklist: Frame, Piers, Roof and Floors

A manufactured home can look perfect in the living room and hide thousands of dollars of trouble underneath. Standard home inspection checklists were written for site-built houses, so they skip the parts that matter most on a mobile home: the steel frame, the piers and tie-downs, the belly wrap, and the lightweight floor decking. This mobile home inspection checklist focuses on those manufactured-home-specific weak spots so you know exactly where to look before you buy, sell or plan repairs.

Start outside and underneath, because that is where the expensive problems live. Then move to the roof, the floors and the utility spaces. Bring a strong flashlight, a moisture meter, a screwdriver for probing, a tape measure, a phone camera, coveralls and a non-contact voltage tester. Plan on two to three hours for a thorough walk-through of a single-wide, a little longer for a double-wide.

Use the list as a screening tool. It will help you decide whether a home is worth a professional inspection, what questions to ask the seller, and which repairs to budget for.

Mobile Home Inspection Checklist: Paperwork First

Before you crawl anywhere, confirm the home’s identity and age. This step alone can rule out a purchase.

• HUD certification label (HUD tag): A small metal plate on the exterior at the rear of each section. Homes built after June 15, 1976, should have one per section. Missing tags can complicate financing and insurance.
• Data plate: A paper label usually inside a kitchen cabinet, a bedroom closet or near the electrical panel. It lists the manufacturer, serial number, date of manufacture, wind zone, roof load zone and thermal zone. Check that the wind and roof load zones match your location.
• Title and serial numbers: Make sure the serial number on the data plate matches the title.
• Foundation and installation records: Ask for any installation certificate, engineer’s foundation letter, or permits for additions and decks.

A home built before mid-1976 predates the federal manufactured housing code. That does not make it worthless, but expect older wiring, weaker framing and harder financing.

Piers, Tie-Downs and Frame

The home rests on steel I-beams supported by piers. If the piers settle or the tie-downs fail, floors sag, doors stick and the home becomes vulnerable to wind.

• Pier spacing and condition: Piers under the main I-beams are typically spaced 6 to 8 feet apart. Look for cracked concrete blocks, blocks stacked without caps, missing shims, rotted wood wedges and piers leaning off plumb.
• Pier footings: Blocks sitting directly on dirt or on cracked pads can sink. Look for footings or pads under each pier.
• Tie-downs and anchors: Check that ground anchors are present, straps are tight, and straps are not badly rusted or cut. Wind zone requirements are listed on the data plate.
• Steel frame: Check the I-beams for heavy rust, cracks, bends or cut sections, especially where plumbing or ductwork was added.
• Level: Use a 4-foot level on floors and countertops in several rooms. A home that is noticeably out of level needs re-leveling by a qualified installer.
• Marriage line on double-wides: Look for gaps, cracked drywall or ceiling separation where the two halves join.

Belly Wrap and Crawlspace

The belly wrap, also called the bottom board, is the fabric or plastic barrier under the floor that holds insulation and keeps out rodents and moisture. Damage here often leads to frozen pipes, high energy bills and pest problems.

• Look for tears, sagging sections, patches and animal entry holes.
• A belly wrap bulging downward often means wet insulation from a plumbing leak.
• Check that skirting is intact and vented, with an access door you can open.
• Look for standing water, damp soil, or a missing ground vapor barrier.
• Check ductwork crossovers on double-wides for disconnected or crushed flex duct.
• Look for signs of rodents such as droppings, nesting material or chewed insulation.

Floors and Soft Spots

Many manufactured homes built from the 1970s through the 1990s used particleboard subfloor. It swells and crumbles when wet, so soft floors are one of the most common repairs.

• Walk every room slowly. Pay special attention in front of the toilet, tub, kitchen sink, dishwasher, washer and exterior doors.
• Use a moisture meter on suspicious areas. Readings noticeably higher than the rest of the floor point to an active or recent leak.
• Look for bouncy areas, dips along the marriage line, and lifted or buckled flooring.
• Check vinyl or laminate seams for swelling, which often signals particleboard damage beneath.

Small soft spots can be cut out and replaced with plywood between the floor joists. Widespread damage means a larger floor replacement, which adds up fast once cabinets and fixtures must come out.

Roof and Exterior

Metal roofs on older homes and low-slope shingle roofs on newer ones both have their own problems. Inspect from the ground with binoculars or from a properly set ladder if you are comfortable, and do not walk on a metal roof that is wet, rusted or badly sagging.

• Roof seams: Metal roofs leak at seams and fasteners. Look for rust, loose screws and old sealant cracking or peeling.
• Roof coatings: Heavy layers of coating can hide previous leak repairs. Ask how often the roof was coated.
• Shingle roofs: Check for curling, missing shingles and exposed nails.
• Ceiling stains: Inside, look for water stains, bubbling ceiling panels and sagging ceiling board.
• Siding and trim: Look for loose or dented metal siding, rotted trim around windows and doors, and gaps where siding meets the skirting.
• Additions, porches and decks: These must be freestanding or properly supported, not hung off the home’s frame. Check for separation at the connection.

Water Heater Closet and Plumbing

Many manufactured homes put the water heater in a closet that opens to the outside. It is a common source of hidden rot.

• Check the closet floor for soft spots, rust stains and water damage.
• Confirm the water heater is rated for manufactured home use and has a temperature and pressure relief valve with a discharge line routed out of the home.
• For gas water heaters or furnaces, look for proper venting and a sealed combustion arrangement. Any gas smell means you leave and call the utility; gas work is for licensed professionals only.
• Look under sinks for leaks, old gray polybutylene supply pipe, and corroded fittings.
• Run water in every fixture and check for low pressure, slow drains and leaks under the home.

Electrical System and Aluminum Wiring

Homes built in the late 1960s and 1970s sometimes used aluminum branch wiring. Aluminum expands and contracts more than copper and can loosen at connections, which increases fire risk if the devices were not rated for aluminum.

• Look at the panel label and visible cable jackets for “AL” or “aluminum” markings.
• Check for warm cover plates, discolored outlets, flickering lights and a burning smell.
• Confirm the panel is not crowded, rusted or showing scorched breakers.
• Look for GFCI protection at kitchen, bathroom and exterior outlets.
• Check that the service entrance and feeder to the home are secure and not damaged by skirting or mowers.

Do not remove the panel cover or pull devices to inspect wiring yourself. If you need to look behind a cover plate, turn off the breaker first and confirm power is off with a non-contact voltage tester. Any sign of aluminum wiring problems, overheating or amateur wiring means a licensed electrician should evaluate the home.

Doors, Windows and Interior Clues

The inside of the home tells you a lot about what is going on underneath. Doors that stick or will not latch, cracks radiating from window corners, and gaps at the top of interior walls often mean the home has shifted on its piers. Check each window for failed seals and rot at the sills. Open every cabinet under a sink and look for water stains. Sniff for musty odors in closets along exterior walls, which can point to condensation or roof leaks.

Typical Repair Costs to Budget For

• Re-leveling: commonly a few hundred dollars to over $1,000 depending on size and pier condition
• Belly wrap repair: small patches are inexpensive; full replacement can run into the low thousands
• Soft floor repair: a few hundred dollars for a small area to several thousand for a whole room with fixtures removed
• Roof coating or seam repair: hundreds of dollars; roof-over systems cost considerably more
• Tie-down replacement: varies by count and soil conditions
• Electrical remediation for aluminum wiring: depends on the method; get a licensed electrician’s quote

When to Call a Licensed Professional

Hire an inspector who specializes in manufactured homes before you close on any purchase. Call a licensed manufactured home installer for re-leveling, pier and tie-down work, since anchoring must meet your wind zone and local code and usually needs a permit. Call a licensed electrician for aluminum wiring, panel issues or any new circuits, a licensed plumber for supply and drain repairs, and a licensed gas professional for gas appliances or lines. Structural changes, new additions and decks attached to the home generally require permits and must be supported on their own footings.