Modular homes?

[K. L. McReynolds]

Examples of the differences(in my experience).

All are done on finished foundations with sufficient curing time achieved.

Factory stick built house(not mobile home, 2x4 or larger wall studs, 1/2" sheetrock on walls, 5/8" on ceilings), 6 months from order to delivery(does not include design time), depending on design. Delivery of completed home(less completed roof) dependent on distance from factory one day to two weeks(out of state). Installation on foundation 4 to 8 hours, depending on one piece or two and access to foundation. Finish roof (partial roof completion or raising hinged sections) 4-8 hours. Hooking utilities and sewer 1-2 days.

Only other requirements are flooring or owner desired additions like their own doors/etc.

Max time is about 7 months.



Factory modular section house with at least 2x4 walls built in 10-24' sections. 4 month wait, delivery 2-4 days, assembly of bare framed sections for exterior walls and interior walls 2+ days(unless you have 50 volunteers, which meant all the walls and 80% of the trusses were installed/sheathed, windows and doors installed in 8 hours). The rest is similar to conventional stick built houses.

Minimum time to dried in about 7 months(not including design time). Then another 2-4 months to finish.

CIF varies considerably depending on design. 1200 sq ft on one level and a conventional wood truss roof takes about 3-6 days to assemble, brace block walls, and pour concrete. Larger, more elaborate designs can take much more time. Roof truss install, sheathing, shingles take 2 days.
Windows/doors another 2 days. Then exterior siding, interior work as desired.

Never did a SIP, but videos show less than a week for basic walls/roof.

So, build times can be similar to experienced crews building stick built. The benefits are less actual on site construction time, faster finished home(especially the complete factory built), and fewer cost overrides.

I was part of a Habitat build where two houses were started on a Saturday morning. One was a conventional stick built, the other was a modular section built. All necessary supplies/materials were on site. The section house had 50 volunteers, four factory reps, and six experienced Habitat crew supervisors. The stick built had 30 volunteers and three supervisors.

Start time was 8AM for the stick built and about 8:30 for the section house(ceremony preceded).
At 4Pm, the section house had all the exterior and interior walls in place, all doors and windows installed and 80% of the roof trusses installed and sheathed. The stick built had a 28' and a 52' wall sheathed and installed.

Quite a difference.

[Lynden]

Doesn't Lindal work through dealers that do the assembly and installation?

I understand that they pre-cut all the pieces though.  It is not clear to me if Sears' homes had all the pieces cut to size or if they simply supplied all the studs and components and you had to do the final cutting yourself.

Here's some history re: Sears homes....

"Precut and fitted lumber was first offered by Sears in 1916. Prior to 1916, the prospective home builder had to cut their Sears-supplied lumber to appropriate lengths. Construction of a house with pre-cut lumber reduced construction time by up to 40% according to Sears. Sears's use of "balloon style" framing systems did not require a team of skilled carpenters, as did previous methods. Balloon frames were built faster and generally only required one carpenter. This system used precut timber of mostly standard sizes.

Shipped by railroad boxcar, and then usually trucked to a home site, the average Sears Modern Home kit had approximately 25 tons of materials, with over 30,000 parts.[4] Plumbing, electrical fixtures and heating systems were not included in the base price of the house but could be included, at an additional cost, with the house order. The Modern Homes features of central heating, indoor plumbing, and electrical wiring were the first steps for many families to modern HVAC systems, kitchens, and bathrooms. During the Modern Homes program, large quantities of asphalt shingles became available. Asphalt shingles were cheap to manufacture and ship, and easy and inexpensive to install. A later feature was the use of drywall instead of the plaster and lath wall-building techniques which required skilled carpenters and plasterers. Drywall offered the advantages of low price, ease of installation, and added fire protection. Local building requirements sometimes dictated that certain elements of the house construction be done professionally and varied to meet requirements of each area of the country. For example, requirements for the depth of the foundation varied by climate and terrain and whether the house was being financed by Sears.

Once delivered, many of these houses were assembled by the new homeowner, relatives, friends and neighbors, in a fashion similar to the traditional barn-raisings of farming families. Other homeowners relied on local carpenters or contractors to assemble the houses. In some cases, Sears provided construction services to assemble the homes. Some builders and companies purchased homes directly from Sears to build as model homes, speculative homes or homes for customers or employees."

[FloridaRetiree]

Am enthusiastic and have few problems with most of the great modular homes I have seen advertised.

That is, . . . if and only if, you have a local licensed contractor to bless and direct
their construction and installation.

[crokett™]

I'm reading this thread and wondering what the difference between 'modular' and 'manufactured' is. FTR, I live in a house that was built in a factory and delivered to the site in 2 sections, but you can't really tell. Also the county thinks it's worth about 1/3 more than I paid for it and the bank thinks it's worth more than that.

[JosephP]

If anybody wants a Lustron home, there is one available in town for free.  It is in good shape (from the outside at least, owner says it is good inside too) - it is on a lot adjacent to his home and he wants the extra space more than he wants the rental there...

If I had a place to put it, I'd probably take it to use as an office/storage.

[Aram]

I'm reading this thread and wondering what the difference between 'modular' and 'manufactured' is.    FTR, I live in a house that was built in a factory and delivered to the site in 2 sections, but you can't really tell.   Also the county thinks it's worth about 1/3 more than I paid for it and the bank thinks it's worth more than that.

It's really dumb nomenclature. Here's my understanding. 

Manufactured homes would have been called "mobile homes," but the wheels come off and they are not meant to be driven around. They are built on a steel chassis (I think always), and may be placed on a foundation at the destination site. Many local building construction codes do not apply -- apparently HUD has defined a separate set of rules for them.

Modular homes, which confusingly are built in a factory, and so obviously are "manufactured" in the normal sense of the word -- are built in sections, transported to the final site, and bolted together on the same type of foundation that stick built homes have. They have to conform to local building codes. I don't know if every modular home is structurally the same as a stick built house (anyone?) but most, if not all, are 2x4 on 16 walls, same joists and floors you are used to, same drywall etc. Many of them are visually hard to distinguish from stick built. 

That's my understanding. I never worked in the building trades. Hopefully someone will correct whatever I got wrong.

[K. L. McReynolds]

It's really dumb nomenclature. Here's my understanding. 

Manufactured homes would have been called "mobile homes," but the wheels come off and they are not meant to be driven around. They are built on a steel chassis (I think always), and may be placed on a foundation at the destination site. Many local building construction codes do not apply -- apparently HUD has defined a separate set of rules for them.

Modular homes, which confusingly are built in a factory, and so obviously are "manufactured" in the normal sense of the word -- are built in sections, transported to the final site, and bolted together on the same type of foundation that stick built homes have. They have to conform to local building codes. I don't know if every modular home is structurally the same as a stick built house (anyone?) but most, if not all, are 2x4 on 16 walls, same joists and floors you are used to, same drywall etc. Many of them are visually hard to distinguish from stick built. 

That's my understanding. I never worked in the building trades. Hopefully someone will correct whatever I got wrong.

Manufactured homes used to be (mobile on steel frames/etc.) moveable. They are covered by different building codes.

Now some are simply stick built, to the same building codes an onsite house has to follow, put on a trailer(two or more trailers, depending on complexity), and trucked to the foundation. Roofs are incomplete to allow for clearance under overpasses and finished when the house is set. Or, in a two piece house, the roof halves are hinged and laid horizontally for shipment. At the foundation, a single piece house is winched over the foundation, mounting bolts(cast in the foundation just like site built) located, holes drilled in sill plates, and the house lowered onto the foundation. Once that is done, the factory built house is indistinguishable from a site built house. Houses built in two or more pieces are placed by crane and strapped to the foundation. Which is the only way, once finished , to distinguish it from a site built.

Modular homes can be complete rooms, assembled on site, conventional wall panels assembled on side, or SIP (foam and OSB sandwich) panels assembled on site.

Another option is the CIF built home. Foam blocks(with open centers and plastic structural webbing in center widths from 4" to 10", are stacked in the design(with wood frames for windows and doors(Called bucks). Temporary wall supports are installed and the concrete is poured into the completed forms. If one had the money, they could build a full sized replica of White House this way. And, it would be bullet proof.


This is a short description, there is a lot more involved in the processes, but, discounting factory build time, most of those first types can be dried in in a day and completely finished in a week or less.

[crokett™]

then by that definition, my house is a modular. it came in 2 boxes. they craned each box onto the foundation and then the crane picked up the roof on each box. the roof was hinged down where the roof rafters meet the top plate on the walls. the last 5' of roof was also folded back on itself. the crane picked up the roof on each box and a pre-framed kneewall was stood up to hold that in place, then after both of the main sections were up, the crew would flip that last 5' up on each side to close the roof at the peak. they had it set and shingled in a day.

[Cooler]

When I shopped for homes 20 years ago I looked at a factory built modular home.  The factory was located on the large plot of land that the developer purchased for the development.  

I was told that it would take about 4 weeks to assemble a home from one of their stock plans.  They would have to pour the basement.  They claimed that even in the winter they could find a day or two where it was warm enough to pour.  

I wanted a full ceiling height in the basement (8 feet), but they were offering 7' high home.  If I wanted taller I would have to take 10-1/2 feet (the forms were in 3½ foot tall modules.  

I did not know it at the time but the 7' high basement did not "count" in the square footage for the home when calculating the property taxes.  It would count if it were 8 feet or higher.  So the extra ceiling height would have been an expensive extra.  

In any case I could get a stock design with plumbing and heating in about 6 weeks.  They were near the end of that development and were not very busy at that time.

[Cooler]

I took a tour of the modular home factory near my house.  The were building basically conventional stick built homes in sections in a factory setting using squaring jigs.  The maximum open width would be 24', which they would transport in two 12' wide sections.  All the roofing was applied except the ridge section. The plumbing was all roughed in and all the electric too.

I saw a house going up near my home.  They dug and installed a modular cement basement with a poured floor.  That went up in two days.  A couple of weeks later the modular home sections arrived.  It looked like a finished home (from the outside) in two days.  It was a few weeks later that it was occupied.

I would not hesitate to buy a conventional stick built modular home. 

But the ones that look like modern structures, I am a bit leery of. 

A conventional home generally goes up in value over the years.  A mobile home, on the other hand, depreciates in value over the years.  I have never seen a study to say where the modern look modular home fits in.  Does it appreciate in value like a conventional home?  Or does it depreciate in value like a mobile home?  Or something in the middle?

Dwell, the architectural magazine has basically devoted themselves to the modern look modular home.  I  wrote to them a few years ago about resale value vs. regular homes and they never printed the letter or investigated the question.  Perhaps they don't want the answer.