Author Topic: Man, we sure don't build houses like we used to.  (Read 135 times)

rcjordan

  • I'm consulting the authorities on the subject
  • Global Moderator
  • Hero Member
  • *****
  • Posts: 7076
  • Debbie says...
    • View Profile
Man, we sure don't build houses like we used to.
« on: September 14, 2018, 09:32:23 PM »
<from Florence thread>

http://puu.sh/BtXEK/ea15a0feb6.jpg

The short answer is that we've moved away from individual strips of tongue & groove sheathing or lathing and replaced it with sheet stock like plywood or -ugh- OSB (chip board).

ergophobe

  • Inner Core
  • Hero Member
  • *
  • Posts: 4175
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #1 on: September 14, 2018, 10:21:12 PM »
Yes, now we actually bolt them down. A modern house can't just roll over like the ones in the photos

Drastic

  • Need a bigger hammer...
  • Global Moderator
  • Hero Member
  • *****
  • Posts: 2338
  • Resident Redneck
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #2 on: September 15, 2018, 03:05:16 PM »
OSB....OSB everywhere. It's a rarity to see actual plywood in construction these days.

The listing agent who first showed our new house touted the "triple I beam" flooring supports. So, naturally when I checked the crawl space, I was surprised to not see steel I beams. He was bragging on a 3 piece engineered product which the main piece is, you guessed it, OSB. Pic:
http://puu.sh/Bvrjn/81685b5df2.jpg

Now that's definitely stronger than a 6" joist, but "triple I beam"?? Fucken salesmen.
« Last Edit: September 15, 2018, 03:11:28 PM by Drastic »

rcjordan

  • I'm consulting the authorities on the subject
  • Global Moderator
  • Hero Member
  • *****
  • Posts: 7076
  • Debbie says...
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #3 on: September 15, 2018, 03:24:16 PM »
Even with plywood, it's not as strong as tongue & groove sheathing. Many old-time structures laid it on a 45-degree angle and nailed it as it crossed every stud or joist. Of course, you could hire a good carpenter for $1/day back then.  IMO, our framing (with real wood and not some engineered crap) is fine though it is a lighter structure than the old post & beam-like framing of 100 years ago.
« Last Edit: September 15, 2018, 03:25:51 PM by rcjordan »

ergophobe

  • Inner Core
  • Hero Member
  • *
  • Posts: 4175
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #4 on: September 15, 2018, 05:05:32 PM »
For cost vs strength vs insulation... I would take SIPs frankly.

>OSB

OSB is inherently twice as strong as plywood in shear, but in some applications, this is offset by nail-holding ability. So it is superior when used in TJIs and SIPs and about equal when used in shear walls.

Quote
Osb is stronger than plywood in shear. Shear values, through its thickness, are about 2 times greater than plywood.This is one of the reasons osb is used for webs of wooden I-joists. However, nail-holding ability controls performance in shear wall applications. So both products perform equally well as shear-wall components.
https://bct.eco.umass.edu/publications/articles/choosing-between-oriented-strandboard-and-plywood/

Plywood is stiffer and, traditionally,  more moisture resistant, so many still prefer plywood for floors and roofs. Modern OSB supposedly does better on moisture. If you have an application where you need to fit 3/4" OSB into a 3/4" channel and it has ever seen water, good luck with that.

But for TJIs, SIPs and shear walls, I'll take OSB.

The right tool for the job.

https://www.builderonline.com/products/product-pros-and-cons-oriented-strand-board-vs-plywood_o

One issue with looking at old houses that survive a storm and saying that the materials and methods are better is that that analysis is subject to survivor bias.

Modern houses are stronger, stiffer, tighter (actually in a modern house they commonly need to add methods to make sure it has adequate air exchange), quieter, more energy efficient.

Just like cars, there have been great advances. Modern cars are just so much better than the cars of the 1970s.

The problem with houses is that the skill of the builder has a huge impact. Unlike cars, there are millions of builders and they range from genius craftsmen to atrocious incompetents or worse. Looking at the houses that have been built in our area in the last ten years, some are built to last for centuries and some are built to last long enough for the contractor to get his last payment from the bank.

Brad

  • Inner Core
  • Hero Member
  • *
  • Posts: 2214
  • What, me worry?
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #5 on: September 15, 2018, 08:55:32 PM »
SIPs are the way to go.

rcjordan

  • I'm consulting the authorities on the subject
  • Global Moderator
  • Hero Member
  • *****
  • Posts: 7076
  • Debbie says...
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #6 on: September 15, 2018, 09:17:49 PM »
I like SIPs but I would like to know more about the foam off-gassing.

>OSB

Just say "No!" Tom

ergophobe

  • Inner Core
  • Hero Member
  • *
  • Posts: 4175
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #7 on: September 16, 2018, 06:46:22 PM »
I like SIPs but I would like to know more about the foam off-gassing.

We came really close to building with SIPs and for reasons long to explain, chose not to. But IIR, the claim is that "cured foam" has minimal offgassing, but there is... the OSB. Traditionally, there have been concerns with formaldehyde offgassing from plywood and OSB and, because of the way it's constructed, more so with OSB. Supposedly, these concerns were addressed in a round of rulemaking by HUD, the state of California, the EU and Japan. I don't trust the EPA on such things, but I do trust the EU. I'm undecided about California... if anything California may tend to go to far, posting cancer warnings on almost every product we own (but then again...).

In any case, most offgassing should get vented to the outside in any case, since you'll almost certainly drywall over the SIPs, whereas your outer layers (housewrap and siding) should be more gas permeable.

All in all, I think I would worry more about a foam mattress (Tempurpedic, Casper) than SIPs. When our house was closed up for 39 days during the fire with all doors closed, we were surprised to open the bedroom and find that it smelled of foam offgassing... which has me thinking about getting rid of that mattress.

Quote
>OSB

Just say "No!" Tom

:-)

As I say, right tool for the job. I'm building a small backyard climbing wall right now. It will be plywood. OSB is the wrong tool for that job. I want rigidity. But I might say yes in another context

ergophobe

  • Inner Core
  • Hero Member
  • *
  • Posts: 4175
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #8 on: September 16, 2018, 06:48:38 PM »
Here's an amusing webpage. It turns out that polystyrene and polyurethane SIP manufacturers are in the habit of saying the other's product will kill you.

https://www.eco-panels.com/blog/63-eps-as-a-carcinogen.html

So maybe you're right.

A friend is building a SIP house though and I really like it. Can't wait to see and smell the finished product.

Brad

  • Inner Core
  • Hero Member
  • *
  • Posts: 2214
  • What, me worry?
    • View Profile
Re: Man, we sure don't build houses like we used to.
« Reply #9 on: September 16, 2018, 09:12:08 PM »
I have a home built with SIPs.  It is built very tight for energy efficiency, however I have a fan circulation system that does air exchanges with outside air. 

It's also pretty quiet, not as quiet as a good brick house would be but way more quiet than my conventionally built home is.

I'm less worried about the SIP panels than the carpet, flooring, furniture and anything with glue in it.