Guys,

What is your preferred method to shield SPF from concrete?  We are not fans of PTL in indoor situations.  Have looked at Timbersil 2x12's but the cost is beyond reach.  I am not a fan of vinyl bucks.  How about 2-3 layers of #30 between concrete and the SPF?  2-3 layers of Tyvek?

Just curious about your thoughts?

Leonard

I use copper gold and treat the portions that will be in contact with concrete

Paladium and platinum also work well.....will never corrode.....

We have the window installers install the buck the day the windows go in. Caulk behind the buck and install as usual.

This will not work for most. We use a removable form in our window and door openings.


Silcone coating then your tyvek or the #30 you mentioned should give you a nice barrier.

I used foam sill seal stapled to the 2x buck. On the window bucks, which are inside the 11" form, I used one 5 1/2" strip leaving about 1/4" of wood each side of the strip exposed to concrete. I'm not concerned about that little bit of contact because the climate here in SW Idaho is very dry. On the door bucks, which are 11" wide, I used 2 strips side by side and folded the foam inside the forms. How well this all worked I really don't know, but from what I've been able to probe I think pretty well.

Next time though, I'm inclined to follow my civil engineer cousin's suggestion to brush asphalt emulsion on the 2x's. Probably would have been faster and easier.

Someone here on the forum said he uses LVL rim board for bucks. After I've seen how even untreated 2 x 6 Douglas Fir twists and turns as soon as the package band is cut I think he may have the right idea!! Anyone who successfully uses PTL for bucks deserves a medal!

I swear I had 2 x 4 studs that twisted and bowed as soon as they sensed being carried through the house doorway!! They were straight in the bundle and crooked 1 minute later on the saw horses!!

I use one layer of 30# with SPF or DF which works fine, typically the concrete curing has the bulk of the moisture used after 7 days.

I agree that pt may cause issues, although I always use pt for my basement/ground level work.

Guys,

Thanks for the replies. As we all know the new PTL is very corrosive to fasteners. Jim, I also agree that below grade one is almost obligated to use PTL. Above grade....well different story. Regular SPF or DF is much cheaper. There are no code violations (I think minimum is 8-12" above grade). Just have to shield from the concrete. Brush on asphalt seems like an interesting idea. I am thinking of 3 layers of 30#, extending sllightly past the buck, stapled up to the buck before the install.

Leonard

Len
Thats the point I was making. You don't need multiple layers to protect the wood, it only needs to be an inplace barrier for the pouring and early curing.

And yes, I have preached many times about the 6" for sheathing and 8" for structural components not required to be pt if they are more than 6 & 8!

Jim,

I don't understand your last point.
"And yes, I have preached many times about the 6" for sheathing and 8" for structural components not required to be pt if they are more than 6 & 8!"

Are you saying that wider components don't need to be pt? 
If so, why not?

Very respectfully,
Larry

Larry
No, thats not what I'm saying.

The IRC2003 building code, pretty much adopted by all the states plus a few amendments stipulates that framing lumber closer to the ground than 8" needs to be PT. However, the typical wood sheathing can extend below the structural members and be as close as 6" above grade and not be treated.

Basically this is why window and door bucks on other than the basement level can usually be untreated SPF or DF. The 30# felt barrier is a moisture barrier commonly used for this purpose, however, it really is not code-mandated. It shows though that someone wants to keep the current concrete moisture in the wall, and not be sucked up by dry wood in direct contact with uncured or fresh concrete.

I've been using KD lumber for the past year or so, we spray twice with deck water sealer in a garden sprayer prior to installation. Can't see why we need to do more, bucks turn out nicer -and lighter- than with PT.

I may just try that method :-)

Thanks

Jim,

Thank you for a clear explanation that ties it all together.

Very respectfully,
Larry

attached is the IRC 2006 code requirements

http://www.wwpinstitute.org/mainpages/documents/2006IRC-Aug06.pdf

anything in contact with concrete/masonry needs to be PT or naturally durable wood (redwood) or protected with an impervious moisture barrier

"anything in contact with concrete/masonry needs to be PT or naturally durable wood (redwood) or protected with an impervious moisture barrier"

Sorry Chris, your blanket statement is incorrect, or at a minimum misleading. My comments follow this section from the IRC2003 Commentary used mostly for clarification purposes by Building Officials. (And yes, I am a licensed one).

SECTION R319
PROTECTION AGAINST DECAY
R319.1 Location required. In areas subject to decay damage
as established byTableR301.2(1), the following locationsshall
equire the use of an approved species and grade of lumber,
pressure treated in accordance withAWPAC1,C2,C3,C4,C9,
C15, C18, C22, C23, C24, C28, C31, C33, P1, P2 and P3, or
decay-resistant heartwood of redwood, black locust, or cedars.
1. Wood joists or the bottomof a wood structural floor when
closer than 18 inches m) or wood girders when
closer than 12 inches (305 mm) to the exposed ground in
crawl spaces or unexcavated area located within the pe-
riphery of the building foundation.
2. All wood framing members that rest on concrete or ma-
sonry exterior foundation walls and are less than 8 inches
(203 mm) from the exposed ground.
3. Sills and sleepers on a concrete or masonry slab that is in
direct contactwith the ground unless separated from such
slab by an impervious moisture barrier.
4. The ends of wood girders entering exterior masonry or
concrete walls having clearances of less than 0.5 inch
(12.7 mm) on tops, sides and ends.
5. Wood siding, sheathing and wall framing on the exterior
of a building having a clearance of less than 6 inches (152
mm) from the ground.
6. Wood structural members supporting moisture-perme-
able floors or roofs that are exposed to theweather, such as
concrete or masonry slabs, unless separated from such
floors or roofs by animpervious moisture barrier.
7. Wood furring strips or other wood framing members at-
tached directly to the interior of exteriormasonry walls or
concretewalls belowgrade exceptwhere an approved va-
por retarder is applied between the wall and the furring
strips or framing members.

This section addresses the need for minimum protec-
tion against decay damage for wood members located
in certain locations.
For those portions of a wood-framed structure that
are subject to damage by decay, the code mandates
that the lumber be pressure-preservatively treated or
be of a species of wood having a natural resistance to
decay.
Crawl spaces and unexcavated areas under a build-
ing usually contain moisture-laden air. These spaces
are required to be ventilated in accordance with Sec-
tion R408 to remove as much moisture as possible be-
fore it causes decay. Wood placed a minimum speci-
fied distance above grade in unexcavated under-floor
areas or crawl spaces as shown in Commentary Fig-
ure R319.1(1) is not required to be either treated wood
or wood that is naturally decay resistant. These clear-
ances below floor joists and beams are deemed to be
the minimum necessary to allow adequate circulation
and removal of moisture from the air and from the
wood framing members. Such clearances apply within
the exterior wall line of the building foundation.
Foundation walls will absorb moisture from the
ground and by capillary action move it to framingmem-

This section addresses the need for minimum protec-tion against decay damage for wood members located

in certain locations.For those portions of a wood-framed structure that are subject to damage by decay, the code mandates that the lumber be pressure-preservatively treated or be of a species of wood having a natural resistance to decay.

Part 2 address "when closer than 8""....
Part 3 addreses only the situation of a slab on grade, it does not apply to windows or doorway above grade such as the first and second floor of an ICF building. because it is more than 8" above grade!!
Part 5 addresses the 6" rule for siding and sheathing.....

For years I also thought "anything wood" in contact with concrete or masonry had to be PT, I was wrong!! These
stipulations clarifying exactly when PT is required is one of the most misapplied applications in regards to code approved work.

James;

 

hey its 2008!     if you used the latest 2006 code you might be more inclined to enforce the correct book

I don't make it up........... I just read it and pass it along

Jim,  

Thank you for your clear and documented postings.

 I have very limited experience working with concrete.  I've read in other threads that concrete wicks water and transports it via capillary action.  Although my impression was that this could raise the water a significant distance, R319.1. does not require a moisture barrier if the concrete-wood interface is at least 8" from the ground:

 Does this 8" limit represent a finding that capillary action in a concrete foundation cannot raise water over 8"? 

If so, does that 8" lift limit impact design decisions (such as vapor barriers?) other than protecting the framing members that contact the cement?

VERY respectfully,
Larry

Chris,

James is correct, I believe in your own document that you added for evidence that quotes the 2006 code says exaxtly what James has said here "2. All wood framing members that rest on concrete or masonry exterior foundation walls and are less than 8 inches from exposed ground."

Not meaning to cause a rift but before you blast someone for a misquote or wrong material maybe you should make sure you are 100% correct and have read fully what you are quoting.

The code is interesting in that it many time makes a sweeping statement like,
"SECTION R319
PROTECTION AGAINST DECAY
R319.1 Location Required.
Protection from decay shall be provided
in the following locations by the use of
naturally durable wood or wood that is
preservative-treated in accordance with
American Wood-Preservers’Association
(AWPA) U1 for the species, product,
preservative and end use. Preservatives
shall be listed in Section 4 of AWPA U1."

Then it lists a whole host of exemptions.

http://www.wwpinstitute.org/mainpages/documents/2006IRC-Aug06.pdf

ICF Contractor

Chris
if you used the latest 2006 code you might be more inclined to enforce the correct book

If you would review your own listed states adoptions, you would find that according to the ICC, Florida still runs under the 2003, wheras La and GA use the 2006.

However, rather than get in a pis.... match, I suggest you reread BOTH codes and carefully interpret their wording. What happens in the code world is ONE OR TWO words clarifies the whole sentence, and it is very easy to stray from the actual definition of what the code requires!

Because I currently work under the IRC2003, IBC2003, MEC2003, etc., etc....I only posted one of the current interpretations for the Section R319- protection against decay. If you look at your 2006 posting, and my 2003 posting for R319....duh, they're the same. The only time a newer code is used for a state or possibly a very large city, is when that newer code has been adopted. Are there differences between the codes, sure there are, but most issues are very minor in nature plus sometimes adding appendices and other paragraphs.

Larry
Does this 8" limit represent a finding that capillary action in a concrete foundation cannot raise water over 8"?

It is probable, but I don't remember where this 8" rule came from, maybe earlier BOCA codes? I always used pt on concrete, until I learned its not always necessary. But if you reread paragraph 3 above about pt vs regular wood on a slab, its the requirement of an impervious vapor barrier which allows or requires one over the other. Now in older homes there are tests one can do to determine whether a barrier is in place, but in most cases its just easier to use pt plates instead of placing a barrier, such as ice and water, under untreated plates.

I'm not sure I follow your question as to 8" design decisions for a VB?

james & icfcontractor;

I was not making a "blanket statement" it was a generalized" statement about wood framing ( not doors & windows) in contact with masonry and/or concrete should be PT or durable.

I still stand by that statement and left the PDF document for all to read and interpret the code exemptions for themselves

James ;

If you want to split hairs...................
 
I am sorry you are incorrect about the Florida code , it does not use the 2003 IRC, it uses the 2004 Florida Building code with 2005 & 2006 supplements

You originally made the "blanket" 2003 IRC reference that was incorrect as well