Replies

1. 
   DanH | Jan 02, 2005 06:57am | #1

   I've heard of it. Eliminates any possible benefit of the wrap as a rain shield (not so important for brick), but shouldn't greatly affect it's primary purpose as a wind barrier. Some extra attention needs to be paid to windows, though, to assure that a proper seal is obtained between window frame and wrap.

2. 
   RalphWicklund | Jan 02, 2005 07:09am | #2

   In Florida and other places where the exterior finishing is either T1-11 or something like Hardiboard which is also does double duty as the structural panelling, the house wrap is installed first. Otherwise, with cladding, including brick, the air and moisture barriers and other flashing for penetrations should be over the OSB sheathing. Brick walls are not waterproof. Brick weep holes or wicking is not always effective or even present. Caulking fails or is neglected. Water enters. OSB disintegrates.

3. 
   Matt_S | Jan 02, 2005 09:04am | #3

   One of the purposes of housewrap is to serve as the point where condensation will form (ie. the dewpoint) and drain. If the housewrap isn't applied to the outside surface of the sheathing, where do you think the dewpoint will form? I won't keep you in suspense.

   The dewpoint will form on the outside surface of the sheathing. Not good.

1. 
   HeavyDuty | Jan 02, 2005 09:34am | #4

   Housewrap has been debated to death in numerous previous posts.

   The main purpose of housewrap is to act as an air barrier, it also helps to direct water away from the building if water gets behind the cladding. I thought it is the recommendation of the manfacturers to install it over the sheathing.

2. 
   Davo304 | Jan 02, 2005 11:54pm | #13

   the dewpoint will form on the outside surface of the sheathing.....

    

   I may be wrong, but wouldn't the dew point actually be on the exterior (cold side) of the VB....which happens to be attached to the studs?...... so therefore the inside surface of the sheathing will be saturarted with moisture?  Either way...I agree, bad situation.

   Davo

1. 
   DanH | Jan 02, 2005 11:56pm | #14

   Tyvek isn't a vapor barrier.

2. 
   Matt_S | Jan 03, 2005 01:03am | #15

   Since the studs and sheathing are heated and cooled with the HVAC, they would be the same temp as the interior of the house.Let me offer an analogy: Sit a glass of iced tea outside in the hot sun. See where the condensation forms?

1. 
   BillHartmann | Jan 03, 2005 01:06am | #16

   The sheathing should be at the outside temp (or near it) after insulation is installed.

2. 
   dIrishInMe | Jan 03, 2005 03:24am | #17

   >> 

   Let me offer an analogy: Sit a glass of iced tea outside in the hot sun. See where the condensation forms?

   <<

   Let me offer an analogy:  sit a beer outside in the hot sun in one of those foam coolie cups.  See where the condensation forms?

   Answer: I never let it sit there long enough to find out :-)  

   But you catch my drift...  Besides, how can you say that the condensation did not form on the inside of the glass too? ;-)

    Matt

3. 
   user-263844 | Jan 04, 2005 07:14am | #19

   Thanks for your response--forwarded to my son Joe.  You are exactly right. 

   Jim Lundy

4. 
   MojoMan | Jan 02, 2005 02:52pm | #5

   I would hope this doesn't mean there will be no barrier between the brick veneer and the OSB.

   Al Mollitor, Sharon MA

1. 
   FramerT | Jan 02, 2005 03:27pm | #6

   As Mojoman pointed out,you still need builder's felt or something before its bricked. You said "contractor"believes tyvek deteriorates by the time the brick veneer gets on, whats gonna happen to that exposed osb?
   I didn't do it....the buck does NOT stop here.

1. 
   user-263844 | Jan 04, 2005 07:22am | #21

   Thanks for your input.  You're right.  Forwarded your comments to son Joe.  His contractor does not understand about how moisture gets in and must have a way out.  Your point on OSB exposure is right on.  Told Joe earlier today OSB must be protected from moisture.

   Jim Lundy

2. 
   user-263844 | Jan 04, 2005 07:18am | #20

   Al:  Thanks for your response.  Yes, the contractor did not see the need to protect the OSB from moisture.  Forwarded your info to son Joe and told him earlier today NO WAY should he allow the contractor to proceed as planned.  Thanks again.

   Jim Lundy

5. 
   dIrishInMe | Jan 02, 2005 03:54pm | #7

   Just to reinforce what the others said, I wouldn't worry too much about the housewrap being in that location, but if the builder intends to install brick over OSB with no felt, or other water barrier to protect the sheathing, I'd tell the builder that the sheathing will be covered or else, do one of 2 things:

   1) don't buy the house, or

   2) if the land is already owned by your son, fire the builder.

   BTW - Tyvek brand housewrap will be negatively effected by UV exposure if it is left exposed for more than 90 days according to their literature.  Other house wraps have different time periods for exposure, and I think Typar can be left exposed indefinitely.
    

   Matt

   
   

   ---

   Edited 1/2/2005 8:10 am ET by DIRISHINME

1. 
   davidmeiland | Jan 02, 2005 07:58pm | #8

   I don't like the sound of it. I've only seen Tyvek over studs if the exterior siding is T1-11 nailed directly over the Tyvek.... the T1-11 is doubling as the siding AND sheathing. There definitely needs to be a barrier (felt) over the OSB behind the brick, and then I would be worried about sandwiching the sheathing between the felt and Tyvek. Seems like wet OSB is unavoidable in this case.

   Lundy should make a quick trip to a local, reputable architect or building designer to review the wall system as built (or as being built, whichever the case). Or, talk to the town's chief building inspector. Or both. Take photos and make drawings. No point in deliberating it much with the contractor. Contractors and the carpenters who work for them have their ways of doing things and will justify them whether right or wrong.

1. 
   user-263844 | Jan 04, 2005 07:29am | #23

   Thanks for your response.  Forwarded to son Joe.  Good point and question about the OSB being sandwiched and moisture.  Have wondered about same question.  The OSB will be protected even if contractor objects.

   Jim Lundy

2. 
   user-263844 | Jan 04, 2005 07:25am | #22

   Thanks for your response--forwarded to son Joe.  You're right on.  The OSB will now be protected.  Contractor tried to convince Joe there was no need to protect the OSB!!  

   Jim Lundy

6. 
   timkline | Jan 02, 2005 08:54pm | #9

   This may be a little bit of overkill, but check these links:

   http://www.toolbase.org/tertiary_printT.asp?TrackID=&CategoryID=1017&DocumentID=2140

   http://www.cmhc-schl.gc.ca/en/imquaf/himu/loader.cfm?url=/commonspot/security/getfile.cfm&PageID=48730

    

   View Image

    

   This diagram shows a window head detail. It doesn't matter if it is metal or wood studs.  You need a vapor barrier on the outside of the wall sheathing.

    

   carpenter in transition

1. 
   user-263844 | Jan 04, 2005 07:41am | #24

   Hi Tim:

   Thanks for your response.  Good sketch.  Good info sites.  Forwarded to son Joe.  I've seen some sort of open mesh plastic used in the cavity so the mud does not block all the weep holes.

   Taunton sells a book authored byJoseph Lstiburek--"Builder's Guide to Cold Climates"--Details for Design and Construction.  Has many sketches of wall designs and what is need to protect the sheathing as well as foundations.

   Jim Lundy

7. 
   dIrishInMe | Jan 02, 2005 11:06pm | #10

   PS - most model building codes require some kind of approved sheathing wrap between the sheathing and the masonry on brick veneer houses.  Last I heard, which was at least a few years ago, PA was in the process of adopting a building code, (IRC?) but enforcement was very sporadic from jurisdiction to jurisdiction.
    
   As long as things already appear to be going south, I'd print out that picture that someone posted above and have someone review it with the builder.  I've never seen that pea gravel detail, although the weep holes and base flashing are essential - as is the sheathing cover.  The weep holes and base flashing are not only important at the bottom of the veneer, but atop window and door openings too (as shown).
    

   Matt
1. 
   rez | Jan 02, 2005 11:24pm | #11

   What exactly does the pea gravel do?

   Act as a screening against insect intrusion?

   Help disperse the moisture more evenly to the weeps?

   or act as a hold down for the lower flashing on the sheathing?

    

   be 'or none of the above.' 

1. 
   Davo304 | Jan 02, 2005 11:48pm | #12

   What exactly does the pea gravel do?..........

    

   My guess is that it keeps mortar droppings from permanently blocking off the weep holes. As you build up a brick wall, mortar can sometimes fall behind it.

   Davo

2. 
   user-263844 | Jan 04, 2005 07:43am | #25

   Thanks for extra input.  Good points.  Forwarded to son Joe.

   Jim Lundy

8. 
   USAnigel | Jan 03, 2005 03:31am | #18

   A house in Willowgrove PA had house wrap exposed for 2 years with out problem ('sides the money for the finishing material)