OSB vs foam board sheathing.

[Guest]

I am having a house built in PA on a hill top that is fairly windy. The builder uses only rigid foam sheathing (1/2"TUFF-R is the brand they use) with metal straps for bracing. When I suggested interest in using a solid sheathing instead to make the house more solid they basically said I was being rediculous and that using the tuff-r would prevent the vinyl siding from warping. This is most likely the house I will stay in for a long time so I want to do it right. I haven't committed to this builder yet and am considering going with some one else that will cosider solid sheathing. I hate seeing warped vinyl siding. Any opions on this are appreciated.

[Guest]

Re: OSB vs foam board sheathing.

Hi RAF,

Just what is it that the builder contends will cause the vinyl siding to warp if OSB or Plywood sheathing is installed? Any siding will warp or look bad when installed incorrectly. Ask him/her to explain the science of their objection and provide you with written documentation or a website where you can go to learn about/further understand this alleged phenomenon.

ONE TEAM - ONE FIGHT!!!

Mike O'Handley
[email protected]

[Guest]

Re: OSB vs foam board sheathing.

RAF,just remember,when someone builds to just meet code they are building to minimum allowable standards set by each state and never let a builder look down his nose at you,your paying the bills.

[Guest]

Re: OSB vs foam board sheathing.

Live on that hill -warping of the vinyl siding may be the least of your problems. But as a compromise - why don't you just have him:

a. do each seperately in either order - leave off the metal T brace w/osb/ply first and then the foamboard. Or with the metal T brace on with osb/ply to outside. You may have to mess around with jamb extensions though around windows and doors.

or

b. do a combination of the two to save on labor by adding a nailbase product (osb/ply bonded to foam) screwed to the studs while still needing the T brace.

or

c. better yet - apply either the foam sheathing or the osb/ply and spray the wall (you can go down to a 2X4) from the insidewith closed cell foam for a very "solid" wall (foam becomes structural) with superior energy/air/vapor performance.

I live in NH - in a house on a hill facing west with no wood sheathing just foamboard and the 2X4 walls sprayed with closed cell foam. It is a solid, quiet, draft & moisture free, energy efficient wall assembly.

good luck!

bg

[Guest]

Re: OSB vs foam board sheathing.

From a vinyl application standpoint, my experience has shown its not so much the sheathing as the quality of the studs that determines the smoothness of the wall. In the end, its the siding that has to make up for any variations behind it. The smoothest wall I've applied vinyl siding to was a foam/concrete wall system.
A second defense against waviness is to pick a premium siding with a thick wall gauge (i.e. 0.046"), a large butt height (i.e. 3/4"), and a small face exposure (i.e. D4 or T3). Avoid thin panels (i.e. 0.040 or less), small butt heights (i.e. 7/16"), and large face exposures (i.e. D5 or higher).

[Guest]

Re: OSB vs foam board sheathing.

Thanks for the information. Those siding dimensions will be real useful. I decided to look for a different builder.

[Guest]

Re: OSB vs foam board sheathing.

I'm glad you found it helpful. Most vinyl manufacturers will offer product with those or similar dimensions. It will really become a personal decision of color and texture/grain. In your case of building on a hill top, a side benefit of the premium lines is they'll have the best wind load ratings as well (150+ mph).

rick

[Guest]

Re: OSB vs foam board sheathing.

Another factor in the final appearance of a vinyl siding job is the consistancy of the fastener application. If any of the fasteners are over driven, they can prevent the siding from moving the way that it needs to, leading to warping and waviness that can be much more noticeable than variations in the wall plane caused by studs and sheathing. That last hammer blow can be hard to judge. I've found that using staples with a gun that has an adjustable depth setting usually gives better results. In addition, staples often increase the wind load rating of the siding. I certainly agree that using higher quality thicker panels is the way to go. However, I elected to go with Certainteed's mid range Mainstreet line because of cost. When the material arrived I found out that the supplier had ordered the top of the line Monogram siding instead. I checked my invoice and found that I had paid for the mid-range that I had ordered. I called my salesman and he checked and told me that ,yep, they messed up and I got a deal. I gave him the option of taking it back but he declined, saying that the restock fee from the manufacturer would make it a wash. I think he also didn't want to let his boss know.

[Guest]

Re: OSB vs foam board sheathing.

CertainTeed eh? One of my old companies... I was a senior product designer/application specialist for CertainTeed/Wolverine/Ashland Davis from 1989-1997. Troy got a good deal on that Monogram.

Troy brings up the Golden Rule of siding: Every panel must move freely after application. I prefer hand nailing personally, but the quality of staple guns with the depth control unrelated to air pressure makes staplers a good method as well. Staplers with depth control via air pressure should be avoided - too inconsistent, especially when running several guns together.

As Troy also eluded to, the consistency of fastener application is very important. Included in that is making sure to not exceed the 16" centers required for fastener placement. When spacing exceeds 16", a long "bulge" can appear. Too tight of fasteners can cause "bubbles" or "oil cans". Examples of these can be seen all too often where cheap siding, and "hit it and git it" construction methods are prevelent.

rick

[Guest]

Re: OSB vs foam board sheathing.

fairly new product -wolverine millenium they have a fabric strip instead of the usual nailer supposed to be good for winds up to 225.cant over nail as the fabric strip lets the panel move all it wants to.have found you have to lap it a bit more though cause it does move more than regular.

[Guest]

Re: OSB vs foam board sheathing.

Hi John,

I worked on developing Millenium while at Wolverine. The fabric is exceptionally strong. I don't know if you've seen the literature, but you can literally hang from a piece of vinyl siding nailed with that fabric - that's strong! The hard-nail ability only applies to the siding though, nailing for unrestricted movement still applies to all the accessories.

That's interesting what you noticed about the extra lapping required - thanks.

rick

[Guest]

Re: OSB vs foam board sheathing.

Rick-recently finished approx.24000sq job using wicker millenium.we started in the beginning of january 2001 and finishedabout oct 15.was able to see the differance between hot and cold hence the extra lapping.first couple of days,sunny and nice,give it a 1/2-3/4 lap cold at night find the laps butted.after my guys got used to it they loved it great product

[Guest]

Re: OSB vs foam board sheathing.

Hi John,

That's good to hear - I'll pass that on to my buddies back at Wolverine.

rick

[Guest]

Re: OSB vs foam board sheathing.

just signed another contract for around 18000sq.millenium today.gotta love the government