What can floor framing be?

[Jane Slaughter]

I'm not an inspector but I have been doing remodeling construction drawings for over 30 years. I have seen some very unusual floor framing systems but I'm baffled about this one.

I have to admit, I'm not familiar with "manufacturered homes" and don't know their history. I was recently in a manufacturered home which was "built" in the mid 70's and the new homeowner wants to remodel.

I cannot find a single exposed area where the home's floor framing is exposed. The best clue is the stairwell (a circular stairway that is going to go away). Here the floor system, including finish floor and ceiling, appears to be only 5.75" thick. The house is 24' wide with either a beam or bearing wall down the middle of it.
Besides the guess of "steel", do you have any ideas/experience with other possible floor framing?

[Gregory Booth]

Manufactured homes can be HUD Code or Modular(Mod). HUD Codes are built to a national (HUD) standard and have their flooring systems built atop steel beams running the length of the home. Since the 80's, the vast majority of homes use 2x6 joists spanning the beams in 12', 14', and 16' widths (nominal). The beams are usually about 99" O.C. Mods are built to state construction standards are are delivered on steel beam trailers-then lifted or rolled onto conventional perimeter wall foundations.

Some early HUD Codes used floor structures of 2x4 joists parallel to the steel beams-they then had intersecting supports perpendicular to the beams-these would be in the 60's and early 70's vintages. The total floor thgickness ends up being in the range you desribe.

However, what you describe and show in your picture does not fit any category --any other pics or descrption?

............Greg

[Jane Slaughter]

Gregory, Thanks for the info and interest.
Ok, I think I've attached two more photos that still just show the floor thickness at the stairwell and the area around it in the basement as well as the main floor. The original house was 58' long & 24'wide. It overhangs the foundation walls approximately 4" on the sides and maybe 6" on the ends. I only see a change in the basement ceiling at the center beam/bearing wall and one 10' wide area under the Master Bath.
I don't see any intersecting supports perpendicular to the center beam.

Also, Guess I was mistaken in assuming that only "mobile" homes were HUD; not modular homes.
Without knowing any better; my definitition of this house would be a "double wide" - but I don't know if that is an official term. This house is in MN, on a lake west of Minneapolis.
Regardless,
has anyone out there ever seen a 2x4 floor framing that clear spans about 11'? Does anyone know if there some sort of 4x4 joist/beams that could have been used?
Does anyone have a suggestion where to find the manufacturer's label in this house? Some vauge memory tells me there should be a label.

[David McGuire]

Labels can sometimes be found inside one of the closets or on one end of the exterior of the home.

[Rod Butler]

This is interesting.

I see insulated metal panels (IMP) used for a walking deck above mfr plants all the time. The ones I see are 4" thick but I am sure they come in many different thickness's. I think I'd consider drilling a hole or two to verify what you have before issuing any design documents.

Let us know what you come up with.

[Scott Patterson]

It is most likely built on a steel I-beam frame with the marriage wall running down the middle. It could have 2x4 or even 2x2 framing in it since homes like this were built under DOT (Department of Transportation) guidelines and not HUD when that home was built.

The subfloor could have been a Masonite type material or plywood back then. It sounds like all of that has been replaced based on what you are telling us.

[Gregory Booth]

As several posters have mentioned, at first glance, it appears like an early version of a mobile home-that is, pre 1976 HUD requirements. You indicate that there is only a center support beam. If it were a mobile double-wide, you would find 2 steel beams, length-wise, under each half and no center beam. The whole affair would then be supported by transverse beams set into the foundation walls. However, based upon your descrition, it sounds as if this is an early version of modular construction that was lifted from a transport trailer and placed upon the foundation, which was built too short/wide (not uncommon occurances). Some late 60's, early 70's mods, meant for apartment complex development, had some wierd framing techniques-one comes to mind that was built here in the Finger Lakes area was Sterling-Homex. When they went belly-up, their inventory was auctioned and many units were built into single family homes that still exist. I inspected one earlier this year on a valuable lakeside lot--it's since been torn down. Sorry for the drift..........Greg

[Garry Sorrells]

Jane,
If the owners are going to be remodeling then why not just cut out a section of ceiling to inspect. Done right an easy repair that will not be noticeable when completed. Thus taking out all of the guess work.

[Gregory Booth]

Jane,
If the owners are going to be remodeling then why not just cut out a section of ceiling to inspect. Done right an easy repair that will not be noticeable when completed. Thus taking out all of the guess work.

you're right.........all the guessing in the world will be trumped by actually seeing what's in there.:)
......Greg

[Garry Sorrells]

you're right.........all the guessing in the world will be trumped by actually seeing what's in there.:)
......Greg

Greg,
There has been so many occasions that a client has asked me to be psychic about what I can not see and want an opinion on an atypical situation. I start running off a list of potential possibilities and after a while stop and explain that exploration is needed to make a actual reliable and informed determination. They then understand that I am not part of the psychic connection network. The client seldom has a real understand that no two houses are built the same, to many humans involved.

[jamie wilks]

This would be a first for me. I have never seen a multi level manufactured home.
I see multi level modular homes all the time, but not manufactured.
Every manufactured home I have seen, has a steel frame supporting the house.

[Gregory Booth]

This would be a first for me. I have never seen a multi level manufactured home.
I see multi level modular homes all the time, but not manufactured.
Every manufactured home I have seen, has a steel frame supporting the house.

...........you are correct. But nobody said it was multi-level.......just that it was on a basement. To be technically precise with terminology: they are all manufactured homes, one type being Modular the other being HUD Code (Mobile home pre 1976);)
...........Greg

[Ted Menelly]

The 6 inch area appears to be at the perimeter of the spiral opening. The rest seems to be standard framing. The post undr the corner is at the base of the real thickness of the floor. I am sure this is headers around that opening and then they infill the rough opening with 2x6.

Just an opinion but I keep spinning the pictures around and that is what I think I am seeing. Those small areas framed in with 2x6 is not a problem at all. Like I said the main rough opening before the stairs and then closed in has much deeper framing.