The Home Improvement Thread

[topfiverecords]

Originally Posted by Mass_nerder

I'm not reversing terms.
I know that tyvek can be an air barrier, but it guards against air infiltration, which isn't a big problem in cool climates. Instead it essential functions as a drainage plane in cool climates. 6 mil poly is a vapor barrier, and vapor diffusion is certainly a concern, it is much less of a problem than exfiltration of humid interior air.
"Air barrier systems can be located anywhere in the building enclosure – at the exterior surface, the interior surface, or at any location in between. In cold climates, interior air barrier systems control the exfiltration of interior, often moisture-laden air"
air barriers
vapor barriers

I'm Intern Architect and also worked for 5+ years as an architectural technologist before that.

You’re approaching it from building science applied to commercial or multi family developments and not traditional construction methods applied to hundreds of thousands of local single family homes built over the last 120 years.

If you use the term air barrier, (which since house wrap has become a loose term) 95% of builders/trades/etc assume you’re taking about the exterior. Tar paper was the standard at the beginning of the 20th century and anyone in their right mind would still use it today over Tyvek or equivalent. Air infiltration is an issue in any climate. I’m aware we have wind here, and lots of it.

[Mass_nerder]

Originally Posted by topfiverecords

You’re approaching it from building science applied to commercial or multi family developments and not traditional construction methods applied to hundreds of thousands of local single family homes built over the last 120 years.

If you use the term air barrier, (which since house wrap has become a loose term) 95% of builders/trades/etc assume you’re taking about the exterior. Tar paper was the standard at the beginning of the 20th century and anyone in their right mind would still use it today over Tyvek or equivalent. Air infiltration is an issue in any climate. I’m aware we have wind here, and lots of it.

Just because it's been done that way for 120 years, doesn't mean we should continue to do it that way when we know it's less effective.

I misspoke though; air infiltration isn't really an issue for moisture control within wall cavities in cold climates, which is what I was originally talking about. Infiltration is still an issue for energy efficiency and keeping pollution/allergens out. Of course it can also technically physically push moisture into the assembly (hence house wrap still being used as a drainage plane material) but that's much less of a problem.

air infiltration

Of course in warm climates, this changes, as the exterior air is warm and humid, whereas the interior air is conditioned to be cool.

[topfiverecords]

Originally Posted by Mass_nerder

Just because it's been done that way for 120 years, doesn't mean we should continue to do it that way when we know it's less effective.

I misspoke though; air infiltration isn't really an issue for moisture control within wall cavities in cold climates, which is what I was originally talking about. Infiltration is still an issue for energy efficiency and keeping pollution/allergens out. Of course it can also technically physically push moisture into the assembly (hence house wrap still being used as a drainage plane material) but that's much less of a problem.

air infiltration

Of course in warm climates, this changes, as the exterior air is warm and humid, whereas the interior air is conditioned to be cool.

Well, this isn’t an “Let’s talk about Alberta Part 9 Building Code, Single Family Building Science and Best Practices thread”. We can start one if you want.

We need to remember the discussion was out of solving Calgary14’s attic rain and mysterious exterior moisture issues on his 2012 build.

What’s your exterior cladding Calgary14?

[Mass_nerder]

Originally Posted by topfiverecords

Well, this isn’t an “Let’s talk about Alberta Part 9 Building Code, Single Family Building Science and Best Practices thread”. We can start one if you want.

We need to remember the discussion was out of solving Calgary14’s attic rain and mysterious exterior moisture issues on his 2012 build.

What’s your exterior cladding Calgary14?

Hahah, nah. I get enough of that at work!
Didn't mean to start a debate.

I still think it could be an interior air barrier issue, which is why it has emerged during cold weather.
But again, I would consult with a building envelope professional.

[topfiverecords]

Originally Posted by Mass_nerder

Hahah, nah. I get enough of that at work!
Didn't mean to start a debate.

I still think it could be an interior air barrier issue, which is why it has emerged during cold weather.
But again, I would consult with a building envelope professional.

It’s all good, same here. I generally get my construction discussion out on another more construction specific forum.

If Calgary14 has stucco, that could be compounding a problem at the wall assembly but sounds like restoration has been looked at there. Hopefully that doesn’t show again, or elsewhere.

You are right it could be an interior barrier issue. The non-vented soffit is definitely a factor. Adding low level venting inputs in the attic may be the easiest to implement to remove more of the humid air out of the attic before it condenses.

Roof pitches, heal heights and attic insulation value are also factors at play.

In low roof slopes the cold plane of the roof sheathing is close to the insulation layer resulting in minimal air space between the two for the humid air to mix with the dry air and exhaust before it condenses on the sheathing.

Many homes were stupidly built with 3 1/4” truss heals which means on low slopes there may only be roughly R9 over ext walls, and R40-60 in the middle. Studies show you get more heat loss at the exterior edges of ceilings than the middle. Forced air heat may play into this along with heals, and that science thing. Temperature difference between the spaces is often the cause for air movement, so the solution to the problem is to get rid of this winter thing.

I’ve seen crazy things though, like bath fan exhaust pipes laying in attics sending all that humid air straight into the attic. Attic hatches with no weatherstripping or insulation. Attic hatches above showers (my 1910 house has this). Skylight shafts with no insulation around the shaft. Plumbing vent chases, chimney chases, wiring shafts all with wide open gaps into the attic. Electricians clearing insulation to install a light leaving a 4’ circle of no insulation. With air loss goes heat and moisture.

[Calgary14]

It has vinyl siding but whats behind that I honestly don't know. At some point this week I hope to get some answers from someone who can come take a look at it from a building envelope perspective, rather than a roofing perspective which is what the focus has been up until now

[topfiverecords]

Originally Posted by Calgary14

It has vinyl siding but whats behind that I honestly don't know. At some point this week I hope to get some answers from someone who can come take a look at it from a building envelope perspective, rather than a roofing perspective which is what the focus has been up until now

I’d guarantee your wall assembly is essentially this then:
Ext
- Vinyl siding
- Tyvek or similar product
- Sheathing, either 1/2” plywood or OSB
- 2x6 Studs
- R12 or R14 Fibreglass batt insulation
- 6mil Poly vapour /air barrier
- 1/2” gypsum board

Whether your electrical outlets are vapour sealed is unknown. I can’t remember at the moment what year that came into code.

In any event, you shouldn’t find water pouring down the outside walls no matter what. Hope you get some answers from the envelope perspective. Please report back what you find or don’t find!

[Brendone]

Originally Posted by topfiverecords

....wiring shafts all with wide open gaps into the attic...

Amazing how much humidity, condensation and ice you can get from a 2 1/2” wiring conduit without a cap. We had one run from our utility room to the attic for future wire pulls when we built. I found water in the utility room floor after a cold spell and was baffled until I climbed up there and found the conduit had no cap. All the warm humid house air travelled up and froze till the conduit was plugged, then started flowing once temperatures went up. Found some water damage on some ceiling drywall at a pot light in the area, so there was probably a lot of frost up there.

[Shin Pad]

Originally Posted by Mass_nerder

I'm not reversing terms.
I know that tyvek can be an air barrier, but it guards against air infiltration, which isn't a big problem in cool climates. Instead it essential functions as a drainage plane in cool climates. 6 mil poly is a vapor barrier, and vapor diffusion is certainly a concern, it is much less of a problem than exfiltration of humid interior air.
"Air barrier systems can be located anywhere in the building enclosure – at the exterior surface, the interior surface, or at any location in between. In cold climates, interior air barrier systems control the exfiltration of interior, often moisture-laden air"
air barriers
vapor barriers

I'm Intern Architect and also worked for 5+ years as an architectural technologist before that.

I've had this discussion with Mass_Nerder before, but polyethylene is not a vapour barrier - it's a vapour re tar der. The thing is, the sheet material might meet the requirements of a vapour barrier, but when you have it installed on the wall, with all the penetrations, etc, it ends up with a perm rating above 1 US perm - thus it is not considered a vapour re tar der not a vapour barrier. Anyway, you and Topfiverecords are both sort of right. The vapour re tar der always goes on the warm side of the insulation. The air barrier can be anywhere in the wall system - it doesn't have to be at the exterior side or interior side (unless you are doing an insulated stud cavity wall like in residential construction where the air barrier (building wrap) goes on the outside of the wall sheathing.

In commercial construction where you have a backup wall - whether it is stud/sheathing or concrete block or concrete or whatever, and the insulation goes on the outside of that backup wall, then you would normally be using a material that is both an air barrier and a vapour barrier (not vapour re tar der) - such as a self adhered membrane like blue skin or similar, which would be installed on the outside face of the backup wall prior to installation of the insulation which would normally be some sort of board insulation and would normally be mechanically fastened through to the studs in the backup wall. Self adhered membranes are considered air/vapour barriers because when installed they seal around screw penetrations, and around all other penetrations through the wall thus giving a perm rating of 1 US perm or less over then entire installation) The cladding would be installed on the outside of the insulation, with an air space between the outside face of the insulation and back side of the cladding - so you would have a "rain screen" type wall (I'm simplifying this but there is a lot more to this than I care to type here).

Anyway, I have worked as an Architectural Technologist (specializing in Architectural Specifications), for 40 years before I retired 2 years ago. Building science is my thing.

[Calgary14]

Thanks for all the info. In early January when I discovered the baseboard was wet, they came and took the drywall and insulation out in that corner to discover the insulation was wet and the wood behind the drywall was wet too. So as of right there there is a bare wall there still as they were doing testing for mold etc up until a week ago. This is exactly where the issue is with water running down the exterior. I’m guessing having a bare wall there wouldn’t help either?

[topfiverecords]

Originally Posted by Shin Pad

I've had this discussion with Mass_Nerder before, but polyethylene is not a vapour barrier - it's a vapour re tar der. The thing is, the sheet material might meet the requirements of a vapour barrier, but when you have it installed on the wall, with all the penetrations, etc, it ends up with a perm rating above 1 US perm - thus it is not considered a vapour re tar der not a vapour barrier. Anyway, you and Topfiverecords are both sort of right. The vapour re tar der always goes on the warm side of the insulation. The air barrier can be anywhere in the wall system - it doesn't have to be at the exterior side or interior side (unless you are doing an insulated stud cavity wall like in residential construction where the air barrier (building wrap) goes on the outside of the wall sheathing.

In commercial construction where you have a backup wall - whether it is stud/sheathing or concrete block or concrete or whatever, and the insulation goes on the outside of that backup wall, then you would normally be using a material that is both an air barrier and a vapour barrier (not vapour re tar der) - such as a self adhered membrane like blue skin or similar, which would be installed on the outside face of the backup wall prior to installation of the insulation which would normally be some sort of board insulation and would normally be mechanically fastened through to the studs in the backup wall. Self adhered membranes are considered air/vapour barriers because when installed they seal around screw penetrations, and around all other penetrations through the wall thus giving a perm rating of 1 US perm or less over then entire installation) The cladding would be installed on the outside of the insulation, with an air space between the outside face of the insulation and back side of the cladding - so you would have a "rain screen" type wall (I'm simplifying this but there is a lot more to this than I care to type here).

Anyway, I have worked as an Architectural Technologist (specializing in Architectural Specifications), for 40 years before I retired 2 years ago. Building science is my thing.

I believe the correct term now is barrier challenged. It is a barrier when it leaves the factory on the roll so you spec for a barrier to be installed, not to turn it into a barrier challenged material prior to installation. When it becomes barrier challenged due to the semantics penetrating it, that’s after my specifications.

[81MC]

Any resident electricians? What I hoped was a simply moving a few devices and adding some lights involves a wiring configuration I’m not entirely sure about.

[PaperBagger'14]

Originally Posted by topfiverecords

I’d guarantee your wall assembly is essentially this then:
Ext
- Vinyl siding
- Tyvek or similar product
- Sheathing, either 1/2” plywood or OSB
- 2x6 Studs
- R12 or R14 Fibreglass batt insulation
- 6mil Poly vapour /air barrier
- 1/2” gypsum board

Whether your electrical outlets are vapour sealed is unknown. I can’t remember at the moment what year that came into code.

In any event, you shouldn’t find water pouring down the outside walls no matter what. Hope you get some answers from the envelope perspective. Please report back what you find or don’t find!

It would be a real easy check for outlet vapor barriers, pick any plug or switch on an exterior wall, pull the faceplate off and shine a flashlight between the cut out drywall and the box itself.

The vapor barrier should be very noticeable. Also I'm not sure when they were added to code, but they've been code for at least 20 years now

[Shin Pad]

Here is the thing about how you call things up on the drawings and in the specifications. Suppose you are doing a project where a portion of it is commercial construction with a backup wall, with air/vapour barrier (self adhered membrane) on the exterior side of the wall and insulation and cladding outboard of that, and then you have a portion of the building that is residential type construction with the traditional stud with batt insulation type construction, with a polyethylene sheet on the inside face of the studs and a building wrap material on the exterior side of the sheathing. So you are calling up the materials as an air/vapour barrier (on the commercial portion), a vapour barrier (poly) and air barrier (building wrap) on the residential portion. This could create confusion on site and in the bidding process. What if the contractor comes back and asks for an extra because he priced out vapour barrier (poly) on the commercial portion during the tender period instead of what you wanted which was the self adhered air/vapour barrier. I have seen this being tried by Contractors - they will try and get an extra on anything they can. So to avoid any confusion, you need to make sure you use the right nomenclature throughout your documents. So I would call the building wrap - exterior sheathing membrane. I would call the poly - vapour re_tarder and I would call the self adhered membrane air/vapour barrier. I would have a separate specification section for each material and the drawings would call out these materials using the same nomenclature so there is no confusion, it's absolutely clear which material goes where. Anyway - another reason for making the distinction between air/vapour barrier and vapour re_tarder.



I have never seen the term "barrier challenged" before, but the important thing is, what you end up with when it is installed - and poly is definitely not a vapour "barrier" once it is installed.


I know in single family residential, you don't have specifications (other than some notes on the drawings), and you are just using 6 mil polyethylene sheet, so it probably doesn't matter what you call it.

[topfiverecords]

Originally Posted by Shin Pad

Here is the thing about how you call things up on the drawings and in the specifications. Suppose you are doing a project where a portion of it is commercial construction with a backup wall, with air/vapour barrier (self adhered membrane) on the exterior side of the wall and insulation and cladding outboard of that, and then you have a portion of the building that is residential type construction with the traditional stud with batt insulation type construction, with a polyethylene sheet on the inside face of the studs and a building wrap material on the exterior side of the sheathing. So you are calling up the materials as an air/vapour barrier (on the commercial portion), a vapour barrier (poly) and air barrier (building wrap) on the residential portion. This could create confusion on site and in the bidding process. What if the contractor comes back and asks for an extra because he priced out vapour barrier (poly) on the commercial portion during the tender period instead of what you wanted which was the self adhered air/vapour barrier. I have seen this being tried by Contractors - they will try and get an extra on anything they can. So to avoid any confusion, you need to make sure you use the right nomenclature throughout your documents. So I would call the building wrap - exterior sheathing membrane. I would call the poly - vapour re_tarder and I would call the self adhered membrane air/vapour barrier. I would have a separate specification section for each material and the drawings would call out these materials using the same nomenclature so there is no confusion, it's absolutely clear which material goes where. Anyway - another reason for making the distinction between air/vapour barrier and vapour re_tarder.

And if you shaped it into a cup form you could call it a bag, or if you lay it flat in your yard you could call it a tarp or any other non-applicable distinction you want to make. You're killing an ant with a sledgehammer here and that just drags the topic away from the original point of use in a single family wall and ceiling assembly.

Originally Posted by Shin Pad

I know in single family residential, you don't have specifications (other than some notes on the drawings), and you are just using 6 mil polyethylene sheet, so it probably doesn't matter what you call it.

We don't have specifications other than some notes on the drawings? Huh?

It doesn't matter what you call it either after it's been installed which is what we're talking about here and not a specification situation on a multi-use development.

Originally Posted by Shin Pad

I have never seen the term "barrier challenged" before, but the important thing is, what you end up with when it is installed - and poly is definitely not a vapour "barrier" once it is installed.

[MoneyGuy]

Water is leaking from our bathroom fan. I’m attempting to dry it out. My wife just had a shower and we’re running a portable humidifier constantly. I should know in a couple of hours if humidity is the problem but I don’t want to go onto an icy roof to check.

Thoughts?

[topfiverecords]

Originally Posted by MoneyGuy

Water is leaking from our bathroom fan. I’m attempting to dry it out. My wife just had a shower and we’re running a portable humidifier constantly. I should know in a couple of hours if humidity is the problem but I don’t want to go onto an icy roof to check.

Thoughts?

Your problems are extreme cold, showers and gravity. Which one can you do away with?

[Red]

Originally Posted by MoneyGuy

Water is leaking from our bathroom fan. I’m attempting to dry it out. My wife just had a shower and we’re running a portable humidifier constantly. I should know in a couple of hours if humidity is the problem but I don’t want to go onto an icy roof to check.

Thoughts?

Most likely condensation. Just let it drip until dry and inspect attic venting in the summer.

[Shin Pad]

Originally Posted by topfiverecords

And if you shaped it into a cup form you could call it a bag, or if you lay it flat in your yard you could call it a tarp or any other non-applicable distinction you want to make. You're killing an ant with a sledgehammer here and that just drags the topic away from the original point of use in a single family wall and ceiling assembly.



We don't have specifications other than some notes on the drawings? Huh?

It doesn't matter what you call it either after it's been installed which is what we're talking about here and not a specification situation on a multi-use development.

Those are just drawing notes. When I have finished preparing a specification for a commercial project, it ends up being a 3" thick book spec. I have done drawing "specifications", which might be one or two drawing sheets, but it is a really short form but usually adequate for the projects I would use it on. Again, you don't usually have a "book" spec for a residential house, but most commercial projects of any size or complexity have book specs accompanying the drawings.



Ok you got me on the joke .

[Nufy]

Is there a industry going rate for railing replacement.

Approx 14 feet with a 90 and then two flights of 7 stairs each to the basement.