The national building code and the alberta building code. That if you beleive what they say.
Where in your framing training did you learn of up-to-date building science, psychrometry and H-A-M (heat, air and moisture) movement?
Where is the definitive text that says “leave an air gap behind the framing and insulation” or was this learned on the street? I have provided a document that has been around since the 1980’s and quite accurate since it’s last major re-write in 1989. Where are your references?
What Section, Subsection, Article, Sentence, Clause or Subclause?
Alberta building code 9.23.2.2 and I stand corrected. the requirement is for 19mm not 25mm.Sorry
A try but no cigar!!!
From the NBC:
9.23.2.2 Protection from Decay
***1) *Ends of wood joists, beams, and other members framing into masonry or concrete, shall be treated to prevent decay where the bottom of the member is at or below ground, or a 12mm air space shall be provided at the end and sides of the member.
2) Air spaces required in Sentence (1) shall not be blocked by insulation, vapour barriers or airtight materials.
These statements are referring to what we call here “beam pockets” at or below grade, not wall framing!! How can we leave a 12mm air space at the ends and sides of vertical wall studs???
There is a lot of misinformation at the street level!!
Here is how it was identified to me how to insulate and stud a basement as I did many as a renovator. If using batt insulation. Minimum 2x4 construction (or 2x3 built out to accomodate insulation R-16) Sill gasket on bottom plate 6 mil ( i used the roll out poly foam). 6 mill vapor barrier on the warm side all holes and joints sealed (Tuck tape) and and where possible use acoustic sealant on upper and lower sill plates. All headers to be insulated (usually R-24) and again vapour barrier sealed with usually acoustic sealant. Never had an inspection fail.
This process would stop all air movement and moisture penetration…in theory. I stopped this process some time ago and went straight to spray foam…solved allot of man hours and insulation/vapour barrier issues.
Sounds like good technique if there is no air space at the wall but what about a moisture barrier (poly or extruded foam) at the wall…have to prevent soil moisture by diffusion or leakage from getting into the wall system.
The black dampproofing applied at the exterior foundation usually emusifies/disolves into soil after 8-10-12 years leaving a black stain and no protection as initially provided. This was recognized by building scientists and in the 1970’s-80’s, the interior moisture barrier (asphalt (ugh!!!) or 6 mil poly) to grade was recommended. Joe Lstiburek later brought in an even better system.
“Never had an inspection fail.”
It’s not what it looks like at the inspection but will the wall still have no problems 10-15 years down the road?
As you well know Brian, what is good today may not be good tomorrow. I believe that I have seen that you believe in Mike Holmes…this (above my post) is the same way he does it. He also uses SM board on walls and floors to create a “thermal break”.
Remember I was talking about existing construction. On new construction the exterior of the home is water proofed, then poly, then a dimple (plastic) product (drainage board I believe its called). So I believe in this case…NEW construction there would be an air space but I have never seen an air space on the inside when spray foaming? So if spray foaming is considered acceptable practice but you maintain that it will cause problems…why is it allowed.
I am not disputing your logic just that air space can only apply to a new home being built…IMO. Basically you have stated that every basement will leak because of the breakdown of waterproofing in 10 - 12 years…no matter what we do on the inside…is that correct?
In the vast majority of houses, what is currently used and required by codes on the exterior of standard concrete foundations is dampproofing, not waterproofing. You seem to believe the bitumin based product that is sprayed or rolled on is waterproofing.
I was not talking of leaking (that does happen later on in some cases) but moisture diffusion through the concrete from the soil dampness…that’s why it is called “dampproofing” …but it does dissolve into soils as time goes on, leaving no dampproofing to protect the basement exterior wall finishes…that is why “Keeping the Heat In” requires the poly to grade on the inside of the foundation…a second moisture barrier for when the original outside fails.
I did not write the code. And its not tar it’s emulsified bitumen.
That was 50%RH at 20C condenses at 10-11C 40% at 20C condenses at 6-7C.
Patrick did not mention there was any visible moisture, condensation, sweating yet mould grew…from the ambient high RH conditions (>65-70%) that were created by the “dead” air in the corner cooling
Sorry Brian I stand corrected…I meant dampproofing…it was early when I posted 7.32am. The air space that I was referring to was the dimple product on the exterior. I stated that it was used in new construction not existing …but good contractors use the same method when replacing weepers and the exterior wall is exposed on older dwellings instead of just the emulsified solution.
From wikipedia
Bitumen is still the preferred geological term for naturally occurring deposits of the solid or semi-solid form of petroleum. Bituminous rock is a form of sandstone impregnated with bitumen. The oil sands of Alberta, Canada are a similar material. Bitumen is sometimes incorrectly called "**tar](http://en.wikipedia.org/wiki/Coal_tar)" (tar is a black viscous material obtained from the destructive distillation of coal](http://en.wikipedia.org/wiki/Coal) and is chemically distinct from bitumen).**
The 2006 ABC states.
5.8.2.3. Installation of Moisture Protection
1 ) Except as provided in Sentence (2), where materials are installed to provide
the required resistance to moisture transfer and their installation is covered in the
scope of the standards listed below, installation shall conform to the waterproofing
requirements of the respective standards:
a) CAN/CGSB-37.3-M, “Application of Emulsified Asphalts for
Dampproofing or Waterproofing,”
b) CGSB 37-GP-36M, “Application of Filled Cutback Asphalts for
Dampproofing and Waterproofing,”
c) CGSB 37-GP-37M, “Application of Hot Asphalt for Dampproofing or
Waterproofing,” or
d) CAN/CGSB-37.51-M, “Application for Hot-Applied Rubberized Asphalt
for Roofing and Waterproofing.”
2) Where the substrate is cast-in-place concrete, and a drainage layer is installed
between the building assembly and the soil, and the assembly will not be subject to
hydrostatic pressure
a) materials and components installed to provide the required resistance
to moisture transfer and whose installation is covered in the scope of
the standards listed in Sentence (I), are permitted to be installed in
conformance with the dampproofing requirements of the standards listed
in Sentence (I), or
b) materials installed to provide the required resistance to moisture transfer
and whose installation is covered in the scope of the standards listed
below, shall be installed in conformance with the requirements of the
respective standards:
i) CGSB 37-GP-12Ma, “Application of Unfilled Cutback
Asphalt for Dampproofing,” or
ii) CAN/CGSB-37.22-M, “Application of Unfilled, Cutback
Tar Foundation Coating for Dampproofing.”
(See A-5.8.2.2.(7) in Appendix A.)
5-10 Division B Alberta Buiiding Code 2006 Voiume 2
So you have to go to PART 5 of the code (Environmental Separation) to find anything to attempt to support your “bitumen” correctness…NOTICE that no “emulsified bitumen” is mentioned in the above but “asphalt” is the correct term!!.. and that tar is allowed for this purpose also!!! And… I imagine the above products would be for exterior application, especially when used for waterproofing.
BTW…Not a thing about interior “dampproofing” in PART 5… Why not try PART 9- Housing and Small Buildings?? 9.13…
To go back to your original post in the thread:
“OK lets start with the NBC. It calls for a bitumen coating on the inside concrete from the bottom of the wall up to the level of the exterior grade.”
No…asphalt or tar… and it does not specifically refer to these in 9.13.2.6**. Interior Dampproofing of Walls **…6 mil poly used as “moisture barrier” (a generic term) is my choice!
“NBC also calls for an air space between the framing and insulation and the exterior concrete wall. This is for the moisture to escape up the space and then out side.”
Have you found this anywhere in the code? I haven’t…
*“NBC also calls for 6 mil polyethylene on the warn in winter side of the framing.” *
Yepp!! But it’s useless unless truly airsealed. But if you use the better system with the foam board on the wall first, leave the VB out!!
“NBC also calls for weeping tile around the perimeter of the foundation and damp proofing or water proofing of the exterior wall. This is dictated by local conditions.”
Can’t argue with this!
BOB I hope you believe in mold now.
1-Vapor barrier, there (hot side of course),
2-Bat insulation
3-Framing is right against the foundation wall, no gap between them
4-Framing is not wet, but also have 19% humidity conductive to mold growth.
5-Foundation is not wet (no water)
SUSPECT: Drainage .
Deficiency : Insulation Basement wall. Fiberglass batting.
Framing: directly on the surface. No clearance.
Styrofoam sheeting 3 feet below grade is the normal procedure.
Basement walls have visible organic growth ( apparent mold ).
http://oee.nrcan.gc.ca/residential/personal/new-home-improvement/choosing/insulation-sealing/basement/khi-inbasement.cfm?attr=4
This issue of no vapour barrier versus vapour barrier has given me endless headaches!
Canadians, at least in Ontario use vapour barrier on the warm side, in the basement, yes, yet studying interior and insulation unit I am reading and fully comprehending the use of no barrier on the inside, it makes sense to me.
We have vapour barrier on our basement, and all walls are dry. Our newly built cottage has insulation blanket, mechanically attached to the wall, a continuous contact with wall so that no convective loops form, this surprised the towns inspector, as he had only ever “heard of this stuff” he would have preferred framing, batt and 6mm poly. Yet here in the southern regions of ontario the blanket is I hear pretty much the standard.
As someone said a few posts back, it might be the new science not to have vapour barrier, but try getting it past the inspector (just checked to see who made this comment, I appear to be on the same page as Brian today).
Now, as I can see in the pictures, the problem is on the inside of the walls, so the problem does lie within the interior, and I think that Brians original comment makes a lot of sense, I know when we let the temperature in our basement get too cool it gets pretty cold and swampy feeling. This has actually only happened since the addition of a/c to the house.
This vapour barrier topic in this area of Canada seems to be getting murkier for me, Ontario’s code is for the use of vapour barrier, that should settle it for me, right!
Mrs. Luuk.
VDB Vapor Diffusive Barrier comes in many forms. Maybe that is what is confusing you.
Try to think or look at it simply. Building science is great but simplify you learning curve first.
It is mixing the 2 components properly (* VDB and Insulation ) that lead to the best result.
Following Brian MacNiech will slow you down. Just a theory.
Some much more advanced, liked, mannered, established and credible, understanding, wanting the best for InterNAQCHI MEMBERS LIKE YOURSELF, HUMAN AND NOT CARTOON CHARACTERIZED, better educated, non pompousness or compulsory egocentrically devoted to ones self, and better versed to accommodate you educational objectives.
Want me to create a list.
You might have to wait a day.
Its almost every PAYING MEMBER HERE.
Sounds like the A/C is oversized for the house or airflows are not properly balanced for the space. You are getting lots of cooling quickly but the air has not had enough passes over the evaporator to remove the moisture…you end up with cool but clammy air as you mentioned.
BTW, as to the main topic here, you seem to be grasping it fairly quickly for a relative newcomer. It will be harder for others that have learned over 15-20-30 years in a system that did not teach all the facts and had a lot of info passed along at the street level!!
Like I said Robert, it’s getting murkier for me, and I need to do a lot more investigating into this. Fortunately I have a husband that I can also talk to about these things when I get a little over my head with the reading.
Brian, the a/c is only a few years old, we are still trying to get the balance right the few days a year we actually need it, LOL.
Oh Robert, please call me Kathy. Thats what my friends call me.