Inspecting Manufactured Homes

                                               Inspecting Manufactured Homes

Sometimes referred to mobile homes, manufactured homes have come a long way. When I first started my home inspection business and would get a call for a “mobile home” inspection, I would always think; “this is going to be interesting”. These should not be confused with modular construction. Modular construction consists of house components built in a factory with very close specifications. These panels or sections are trucked to the building site and placed on a foundation. Most manufactured homes are normally built in one or two pieces.  If the home was built prior to June 1976, there were no universal building standards required. From 1976 to 1994 manufactured homes were built to a single HUD standard. While better than homes built prior to 1976, there were still some issues with these homes. Since July 1994 every manufactured home has been required to comply with the Manufactured Home Construction and Safety Standards or HUD Code. Part of this code was conformity with certain wind load zones. Any manufactured house I am hired to inspect built prior to June 1976 I warn the owner that it was probably built with no industry standards. I also let them know that homes built prior to July 1994 may also be substandard construction and have other issues that have been rectified since that time. Look for steel tags on the outside of the home that contain build information. What are some of the issues with manufactured homes that a home inspector should be looking for:

 

• Push on exterior walls to ensure they are solid. Movement in exterior walls may indicate rot at the floor or roof areas
• Look for spot spots in the floor
• Wavy floors / unleveled floors
• Sticking / damaged doors and windows
• Older mobile homes used a compressed fiberboard that would rot over time. Newer construction now employ ¾ inch water resistant plywood
• Polybutylene Pipe should be removed
• 100 amp electric service is recommended
• Water stains on the ceiling and walls (you should be able to walk most modern manufactured home roofs)
• Check underneath the home and ensure any pipes are insulated
• Insulation missing or hanging down
• Animal nests
• Foundation blocks should be plumb and not damaged
• The house should be properly attached to the foundation piers
• Deflection of the main beam
• Perimeter blocking normally used for additional support at larger openings greater than 4 feet should not be rotted or damaged
• The house should be properly anchored or strapped to the piers or foundation supports. Manufacturers have specific recommended anchors. Sidewall anchors are located on the long side of the house. End wall anchors are located on the short side of the home. Centerline anchors are located underneath the marriage walls of a double or triple wide home (see diagram).

What is Street Creep?

 

What Is Street Creep?

 

This is a term that I have never used in my home inspection reports. Because we are only inspecting one house and not an entire neighborhood; we would not necessarily be able to determine if the compromised foundation we are inspecting is limited to just that house. However we see many areas that are prone to foundation issues. I know every time I get a call for an inspection in one of these towns, I understand there is a chance there will be foundation issues. Again, we are only inspecting one house, so this term would probably not be put on a report. I had to do a little research on Street Creep

Street Creep, is a slang for movement, shift or expansion in concrete streets or sidewalks. Force or pressure, caused by expansive soils, heavy vehicles, and long term settlement, pushes the street or walkways against the driveway and possibly into the home's foundation producing serious cracks in foundation walls. This problem may be more significant on homes with concrete driveways and attached garages. Homes located at the end of "T" intersections, at the end of cul-de-sacs, and on the outside of a curve are especially susceptible to Street Creep damage. Homes built on hills are more susceptible to creep because gravity will induce paved streets and driveways to "slide" downhill.  Although this is a national problem, it is more prominent in wet areas and areas with expansive clay soils. Expansive soils expand significantly when saturated with water. This expansion is largely due to a chemical attraction of water molecules between layers of clay minerals called Smectites. Dry regions experience the downhill slide scenario. Typically, it is not as noticeable in regions without basements but it still occurs.

 The most common preventative fix for street creep is installing an expansion joint between the slabs to absorb the flex. Expansion joints, also called isolation joints, are used to relieve flex type stresses due to vertical movement of slab-on-grade applications. An expansion joint is simply a buffer made of a rubberized material inserted between two slabs of concrete. Properly installed, it will shrink and expand as the concrete moves, absorbing the pressure and stress of the movement before it starts cracking and shifting foundation walls. The driveway may already have an expansion joint but Street Creep may still occur if it not installed properly. Some individuals recommend installing a vertical flexible buffer joint in the foundation walls. So what are things a home inspector could look for:

• Take a screwdriver and try to tamp it down between the expansion joint and the concrete. You should be able to drive the screwdriver or knife blade down a good 4-5 inches. But, if you're hitting concrete at just 2 or 3 inches, the expansion joint is not installed properly.
• Most contractors will pour the entire driveway and then while the concrete is still wet insert the expansion joint material into the wet concrete. If the depth of the concrete exceeds the width of the expansion material, there can be inches of concrete beneath the expansion material that renders the expansion joint useless. When the slab expands it will push the concrete underneath the expansion material and could then push into foundation walls causing damage to the home.
•  Check expansion joints: If the joints seem unusually tight or compressed -- you might say, "squeezed" or "crushed" – there may be a problem.
•  Check garage floor / foundation walls: If there are cracks in the foundation, outside or in, or if the garage floor slab is pulling away from the garage wall (foundation) this may indicate an issue.
•  Remember, these are just possible indicators of Street Creep. If you see real concerns, note it in your report and refer a structural engineer or a professional foundation repair contractor to further evaluate. 

Inspecting Residential Entrance Ramps

 

Inspecting Residential Entrance Ramps

                                                                

I see many entrance ramps and often times my clients are planning on removing them. Every so often, they plan on keeping them in place. I inspect the physical condition of the materials, stability and visually look at the pitch. However, there are requirements that meld the building codes and ADA requirements. We see this also in other areas of the house. If the house is being build for ADA compliance, the codes may be altered to accommodate these requirements. The guidelines I will outline can also be modified to accommodate the individuals needs; however safety and egress requirements must be maintained. Remember, the remap will probably serve as a means of egress and these requirements also come in to play. The ADA requires a slope of 1:12. So basically if the door entrance threshold is 24 inches off of the ground, you would need a 24 foot long ramp. The maximum height of any section of ramp should not exceed 30 inches. If the height does exceed 30 inches a flat rest platform should be in place before the ramp continues. The minimum width of a ramp between hand railings should be 36 inches. Hand railings must be installed; therefore the deck of the ramp must be at least 42 inches wide to accommodate the width of the hand or guard rail. So what else should a home inspector be looking for when inspecting entrance ramps:

 

• Minimum door opening is 32 inches (clear width = measurement taken between the face of the door and the stop of the frame with the door open 90 degrees)  
• Handrails or guards must be installed if the ramp has a rise more than 6 inches or longer than 72 inches on both sides
• Tops of hand rails should be mounted between 34 & 38 inches above the ramp surface and continuous
• Spaces between the ramp and any wall or surface should be at least 1 ½ inches
• Ramps over 30 inches above ground should employ railings with spindles and a curb stop to ensure the wheels do not go over the sides of the ramp
• Curb guards or barriers shall be at least 4 inches high
• Maximum height of ramp should not exceed 30 inches per run
• There must be a flat landing at the top and bottom of all ramps
• Landings should be at least as wide as the ramp and a minimum of 60 inches by 60 inches
• The minimum headroom for all areas of the ramp must be at least 80 inches
• The floor or ground surface of the ramp run or landing shall extend 12 inches minimum beyond the inside face of a handrail
• Non-slip materials should be used for the ramp surface
• Ramps should be designed to ensure water does not accumulate on walking surfaces

Inspecting Synthetic / Composite Engineered Roof Coverings

            Inspecting Synthetic / Composite Engineered  Roof Coverings

 I’ll never forget the first time I saw a polymer slate roof covering. I first looked with my binoculars, as I always do before climbing. I was struck by the incredible condition of the “slate” tiles on this very old lake house. However when I went up the ladder, I discovered they were a rubberized material. Since then I have seen many. Although the materials used are very durable; it is the installation that can be problematic. There have been some manufactures that have had issues with their product materials in the past. Most of the newer products are very durable and if installed properly should have a long serviceable life. However it is important that other materials including flashing and fasteners are also durable. We normally refer to these coverings as just “composite” because of the many different materials used like: rubber, plastic, and other polymers. It is much more expensive than conventional roofing materials; however the serviceable life, if installed properly is longer. Composite roof coverings will tend to fade or oxidize over time. If you observe different colors / variations in different areas; that may mean that the shingle bundles were not mixed prior to installing. The installer should mix shingles from different bundles to ensure they are properly blended due to color variations. Special installation requirements are recommended for slopes of 2/12 or less. Composite shingles should not be installed on flat roof surfaces. I have outlined broad recommended guidelines. The specific manufacturer installation recommendations should always be referenced. What should a home inspector be looking for when inspecting composite roof shingles?

 

• Snow guard devices should be installed
• ½ Plywood is the minimum thickness required for 16” on center rafters, although 5/8” is recommended. 5/8-inch plywood is required for 20” rafter spacing or greater. OSB is not recommended.
• Minimum 1 ½ ” large head ring shanked roofing nails Stainless steel are recommended
• Nails must be fully covered by shingles and not visible in joints
• Where applicable, only a “pure silicon” sealant should be used to cover up exposed nail heads or to seal joints on ridge caps. The sealant should be color matched
• Every shingle should have 4 nails
• Every cap should have 2 screws
• It is important that the head of the nail not be driven below the top surface of the shake. This may cause leaks in this area.
• The joint between 2 shakes in one course should never be closer than 1 ½” to a joint below or above it.
• A Synthetic underlay is required. Ice / water shield may also be used
• The second course should be installed directly over the starter course, but should project a maximum 1/2" beyond the starter course (drip edge)
• The exposure should be less than 9 inches (7-7.5 normally). (This will vary depending on the shingle size and manufacture)
• A 24” wide W-flashing (heavy gauge) should be used in the valleys
• Stainless steel flashing is recommended

Inspecting Modern Flat / Low Slope Roof Coverings

 

Inspecting Modern Flat / Low Slope Roof Coverings

 When I first started conducting home inspections many of the flat or low slope roofs were covered with roll asphalt for residential applications or built up roofing for commercial. Although some people may still use roll roofing, and it may have its place; most modern flat roof coverings are made from newer, more durable, and more waterproof materials. Some of the materials that are commonly used for flat roofs are IRMA – Inverted Roof Membrane Assembly which is widely used for commercial applications. Normally you would not see this on a residence. IMRA incorporate insulation in the assembly and have a protective coating that may contain gravel. Modified / Polymer Bitumen which can be Atactic Polypropylene or Styrene Butadiene Styrene is a rubber like compound that is installed in sheets. Elastomeric or EPDM are sometimes called rubber roofing. PVC or plastic roofing materials are also available. These types of materials are most common for modern flat roofs. Some bitumen coverings may be prone to damage from the sun’s rays unless they are coated with ultraviolet protection. Bitumen materials can also be reinforced with fiberglass. Flat roof covering materials can be applied by heating (torch down), peel and stick, or glued down. It will be difficult for a home inspector to identify the different types and specific materials of bitumen. We normally refer to these types of coverings in our reports as a “Single Ply Membrane.” Here are some of the things home inspectors should be looking for when inspecting single ply membranes on flat roofs:

 

·       Seams facing the wrong direction which could cause water entry

·       Cracking or splits in the membrane

·       Blisters / wrinkling

·       Any areas that have been repaired or patched

·       Seams that are not overlapped at least 3 inches

·       Areas that have “bubbled” or are not properly attached to the substrate

·       Ponding / standing water

·       Any puncture or tear in the material

·       Side & end laps should be staggered

·       Flash points especially around air conditioning systems due to vibration

·       Flashing around parapets

·       Flashing around skylights

·       Flashing around any roof drains

·       Examine any drains that travel through the interior from underneath if possible

·       Ensure the water is draining properly including the drainage system / gutters

Revisiting Attached Garage Fire Separation

 

Revisiting Attached Garage Fire Separation

                                                             

Many home inspector training manuals and continuing education courses address the fire separation requirements between an attached garage and living space. Specifically; fire rated drywall, self closing fire rated door, and ensuring the garage is 4 inches below the living space (although this may be waived for ADA compliance). I have seen some inspectors call out a wood door.  Also any pilot / flame in the garage should be 18” above the floor. However fire separation requirements have been revised and expanded. For instance in the IRC – R302.6 states in part that fire rated gypsum board shall not apply to garage walls that are perpendicular to the adjacent dwelling unit. Also, any openings from a garage directly into a room used for sleeping purposes are not permitted. Fire blocking is also required to eliminate concealed draft openings and to form a fire barrier between stories, and between a top story and the roof space. Fire blocking in wood framed construction should be in the following areas; in concealed stud spaces, vertically at the ceiling and floor, horizontally at intervals not exceeding 10 feet, at connections of soffits, dropped ceilings, and cove ceilings. So where should a home inspector be looking for fire separation:

 

• Fire separation doors should be solid wood doors not less than 1 3/8” thick, solid or honeycomb core steel doors not less than 1 3/8” thick OR 20 minute fire rated doors
• Enclosed accessible space under stairs shall have walls, under stair surface and soffits protected with ½” gypsum board
• All doors should be equipped with a self closing device
• Ducts in the garage penetrating the walls or ceilings separating the dwelling from the garage should be a minimum of No. 26 gauge steel, 1 inch minimum rigid nonmetallic or other approved fire rated material
• No Duct openings are permitted in the garage
• Any openings around vents, pipes ducts, cables, or wires shall be sealed with approved material to resist the passage of flame, smoke, and products of combustion
• Wood Structural Panel floor structures shall be required to have a 5/8” gypsum wall board
• Wood floor assemblies using dimensional lumber equal to or greater than 2 inch by 10 inch or any other approved floor assemblies demonstrating equivalent fire performance do NOT need 5/8” gypsum wallboard (basements only)
• The annular space between the wall membrane and any electrical box shall not exceed 1/8”
• Two family dwellings should be separated from each other by wall and floor assemblies having not less than a 1 hour fire rating
• Two family dwellings equipped with an automatic sprinkler system should have a ½ hour wall and floor assembly separation 

Inspecting Modular Built Homes

 

Inspecting Modular Built Homes

Many people confuse modular homes with manufactured homes. Mobile or manufactured homes are built on steel frames called chassis and they cannot be removed. The chassis are used to support the homes and transport them to their permanent locations. These homes can either be placed in “parks” where other manufactured homes are also placed or be fixed on a permanent foundation, which may qualify them as traditional homes.

Modular homes are built in units that are joined together on-site and, unlike a manufactured home; they can be built as a multiple story house. Modular homes are built with wooden beams that use steel supports which make it possible for the modules to be stacked, allowing the homeowner to have a basement and multiple stories.

Modular homes are built with a process that involves the construction of components in a factory. It starts with a wood frame floor built to attach the wall panels later. The builders will then use fasteners to attach the wall panels. The window openings are already cut out before they are attached. As the structure is built, the drywall, ceilings, plumbing, and electrical wiring are installed under the close supervision of inspectors.

The roof is attached in one of two ways depending on the builder. Some manufacturers will build the roof and then set it on top of the walls. Other companies will send the roof separately and attach it on-site.

The final step is adding the exterior and interior finishes. The buyer can customize their own finishes such as the siding, the cabinets, flooring material, backsplash, vanities, countertops, and many other finishes.

The modular units, are usually shipped with a layer of plastic wrap suitable for transportation purposes only. Failure to erect these assemblies on a timely basis may result in serious weather damage and molded areas. Modular homes are inspected like a “stick built” house; however there are some areas that an inspector should pay close attention to:

- An energy seal should be installed by the factory around the perimeter of the marriage wall.

- To ensure an energy-efficient seal between the modules, a foam gasket or other sealant should be used for this insulating process.

- The perimeter rail of the structure is nailed to the sill plate with 16d nails @ 12” O.C. (For basement sets, all lally columns are located per the recommended schedule and lagged to marriage wall floor rails/girders with four 3/4” x 4” lags each one preferably into each rail. Additional columns are required under each side of marriage wall opening in excess of 52”.)

- The first two modules are bolted together, using 1/2” through-bolts.

- If the home is a two story, the rails of the first floor are bolted together with 1/2” bolts @ 4’ O.C.

- The third module should set on top of the first module, in the same manner as the first. The second floor rails should be fastened to the first floor ceiling rails with 16d nails @ 12” O.C.

- Spray foam is put in place around the marriage wall perimeter.

- Roof center beams must be nailed with a 16d nail @ 8” O.C. in height and 12” O.C. in length, staggered, after leveling the beams to each other.

-  Fire stop should be installed in chase areas to assure a maximum of eight feet of vertical distance.

- For an open roof system; fasten truss knee wall to ridge or rafters as per plans.

- Ensure floors are level and not damaged

- The center beams should be bolted together per specifications

- Check factory installed interior / exterior doors for proper working order.

- Drywall cracks, especially at marriage wall openings.

- Check the connection of water lines between modules

- Connection of electric panel to main service and between modules. There may be electrical connection junction boxes where the modules are joined

- Connection of hot water heater to main plumbing pipes.

- Connection of mechanical equipment, furnace, air conditioning, etc., to main systems.

- Ensure there is a bottom sheathing board that completely covers the sill plate

- Examine sheathing splice at marriage wall openings.

- Examine marriage wall doors and cased openings.