Missed Opportunity

[vinny11950]

Playing the role of nosy neighbor, I have been watching in horror as this new home is being built in a nearby neighborhood. It is a pretty pricey part of town, so I was surprised when I saw them using Dens Glass sheathing covered with brick, on a steel structure.

I would have thought adding a couple of inches of foam insulation between the brick face and the Dens Glass would save money in the long run for heating and cooling. And now would be the time to put it on.

Also they don't seem to be adding the moisture barrier in long segments, rather they are patching it in as they complete parts of the walls.

Maybe the brick they are using has higher r value, but I doubt it. And I can't say I am crazy about the Dens Glass, from what I have read it is not a strong as plywood sheathing. And today it is raining pretty hard so it will be getting very wet.

Overall, it looks like a developer bought the lot and is just slapping the home together to build it and sell it as quickly as possible.

 

[valuman]

Stories like this one always make me scratch my head and wonder when we'll wise up and institute energy efficiency minimums in the building codes in the US. Penny wise and pound foolish, we are.

 

[vinny11950]

Exactly, "penny wise and pound foolish."

Looking at the windows a little closer shows the flashing detail to be wrong. I guess if they overlap the moisture barrier over the tape on the top of the window frame it will work, but I thought the moisture barrier gets tucked into the window frame and then the window is installed.

 

[BIGDADDY]

Maybe they are just using the Dens glass sheeting for the purpose it's made for which is behind brick and for moisture and mold control. They might be installing a good amount of insulation in the walls. Did you get a look at their plans?

 

[vinny11950]

Maybe they are just using the Dens glass sheeting for the purpose it's made for which is behind brick and for moisture and mold control. They might be installing a good amount of insulation in the walls. Did you get a look at their plans?

True. I have not looked at the plans but have been driving and looking at the structure since it has been going up. The steel frame didn't look outsized to hold more insulation inside, but still wouldn't you want foam insulation over the frame to prevent thermal bridging? Especially on the metal frame.

It is hard to explain, but the whole project just looks sloppy, like they are not paying attention to the details.

 

[Highbeam]

Assuming the builder is building speculatively or for the majority of Americans he is doing exactly what he needs to do to maximise his profits and have a successful business. Building to code is quite literally "standard".

You want a better home with wiser investments in efficiency then you need to be the guy paying for it.

 

[valuman]

Assuming the builder is building speculatively or for the majority of Americans he is doing exactly what he needs to do to maximise his profits and have a successful business. Building to code is quite literally "standard".

You want a better home with wiser investments in efficiency then you need to be the guy paying for it.

Therein lies the problem.

 

[woodgeek]

Yar, with all the construction around, who needs TV?

My (son of a master carpenter/GC) dad came to visit for a week and set up achair near the window where he could watch the McMonstro house being built across the way. Every evening he would regale me with the tales of poor workmanship and buffoonery, point out the crooked shingles on the roof (done from both sides without a chalk line), etc.

The climax was when the crew showed up in their giant pickup, and it was then clear that they had locked their keys and all their tools in the truck! We got to watch them try to break into it for a couple hours (without tools) before getting relief from a buddy they called in with a spare key.

I would have felt bad for them, but I am sure they got paid for a full work day.

 

[Where2]

There's 8,000 sq. ft. houses going up like that near me. Drop a couple of $M on the house, and you too can sign up to spend $500/mo on electricity. I still don't see why my utility is concerned about PV systems encroaching on their business model. Wait until that guy with a few $M to spend on a house puts two Tesla's in the garage.

 

[BIGDADDY]

True. I have not looked at the plans but have been driving and looking at the structure since it has been going up. The steel frame didn't look outsized to hold more insulation inside, but still wouldn't you want foam insulation over the frame to prevent thermal bridging? Especially on the metal frame.

It is hard to explain, but the whole project just looks sloppy, like they are not paying attention to the details.

It's so easy to criticize what other people are doing or how they are doing it. Isn't it?

 

[vinny11950]

It's so easy to criticize what other people are doing or how they are doing it. Isn't it?

It is a bad habit of mine, but I think it also comes from a desire to make things better, even if you can't improve a situation that is out of your control hopefully the critical thinking helps you in a situation down the road.

Aside from that, wouldn't you want more insulation on the walls to protect against the increased thermal bridging of steel stud walls?

Or better application of the moisture barrier and better detail on the windows to prevent water leaks in the future?

I even saw a big gap/rip on the top of one of the foundation walls, as if they poured the concrete but didn't do it right so this big v-notch gap appeared. I imagine they can patch it but why does it have to be patched in the first place?

If the professional builders don't get it right in the beginning, what hope is there for humanity? Or the common home owner down the road.

 

[begreen]

Locally at least, a professional builder does not mean one will get a professional job. I found a good resource is to speak with the sub-contractors. If the finishing contractor is full of tales and complaints about out of square walls and unlevel floors, you know there are underlying problems being covered up. Our old house had a "professional remodel" in 1984 that I am still redoing and correcting buried errors.

 

[brian89gp]

If the professional builders don't get it right in the beginning, what hope is there for humanity?

Professional builders are giving buyers exactly what they want. Big, shiny, and cheap. There are well built houses out there and they tend to cost accordingly.

I live in a 2600 sq/ft house (plus an attic and a basement, both unfinished) built in 1890. Actual replacement value is roughly 600k, number gotten from insurance companies since they tend to know how to factor that very accurately. So.....who wants to spend 600k on an extremely well built 2600 sq/ft house??? Nobody I know of even if it is for a exceedingly sturdy house.

 

[Oldman47]

I am building my own home and no, I do not have anything but OSB and house wrap outside of my 2x6 walls. After that I just tacked on the vinyl according to the manufacturer's recommendations. If that is all that you can see you will think me a bit foolish since even the Roxul I use to insulate it is only rated to R-23. Now fast forward to what you cannot see. My next delivery was the 2x4 studs that I used to build the inner layer of the outside walls. I set the 2x4 walls back a 1/2 inch because wood is not steel so you need to allow for it not being perfectly straight. I tied the 2 walls together at every window and door opening so that I would have no issues with things shifting as the house "settles" over time. All outer wall plumbing is in that inner wall area and all wiring in the outside wall of the house also runs in that 2x4 wall. The outer R-23 runs completely uninterrupted except at penetrations like the outside lighting and the hose bibs that run straight through both walls to the outside and of course at windows and doors. The inner 2x4 wall gets R-15 Roxul insulation and is the only thing that has anything like receptacle wiring running through it. Just for completeness in the description I applied my moisture barrier to that outer wall before I built the inner wall. That means it is about 60% of the way between the interior and exterior of the home's insulation. I put it there because studies conducted in true heating challenge areas, in Canada, seem to show that is the best place for a moisture barrier relative to the insulation. Now I have some nice R-38 walls with an ideal moisture barrier location and a separate air space about 1/2 inch thick in my walls. I also have added R-60 cellulose to my ceilings. I am running a 2 stage Waterfurnace at the stage 1 only this winter and am seeing utility bills under $100 while I continue to finish the building inside.
Be careful how quickly you judge what you can and cannot see.

 

[vinny11950]

I am building my own home and no, I do not have anything but OSB and house wrap outside of my 2x6 walls. After that I just tacked on the vinyl according to the manufacturer's recommendations. If that is all that you can see you will think me a bit foolish since even the Roxul I use to insulate it is only rated to R-23. Now fast forward to what you cannot see. My next delivery was the 2x4 studs that I used to build the inner layer of the outside walls. I set the 2x4 walls back a 1/2 inch because wood is not steel so you need to allow for it not being perfectly straight. I tied the 2 walls together at every window and door opening so that I would have no issues with things shifting as the house "settles" over time. All outer wall plumbing is in that inner wall area and all wiring in the outside wall of the house also runs in that 2x4 wall. The outer R-23 runs completely uninterrupted except at penetrations like the outside lighting and the hose bibs that run straight through both walls to the outside and of course at windows and doors. The inner 2x4 wall gets R-15 Roxul insulation and is the only thing that has anything like receptacle wiring running through it. Just for completeness in the description I applied my moisture barrier to that outer wall before I built the inner wall. That means it is about 60% of the way between the interior and exterior of the home's insulation. I put it there because studies conducted in true heating challenge areas, in Canada, seem to show that is the best place for a moisture barrier relative to the insulation. Now I have some nice R-38 walls with an ideal moisture barrier location and a separate air space about 1/2 inch thick in my walls. I also have added R-60 cellulose to my ceilings. I am running a 2 stage Waterfurnace at the stage 1 only this winter and am seeing utility bills under $100 while I continue to finish the building inside.
Be careful how quickly you judge what you can and cannot see.

Looks like you didn't miss the opportunity to add insulation to your construction.

Would love to see photos of the double walls, insulation and moisture barrier, if you have any and don't mind sharing. Sounds like a very good system to use.

 

[CaptSpiff]

I am building my own home and no, I do not have anything but OSB and house wrap outside of my 2x6 walls. .... My next delivery was the 2x4 studs that I used to build the inner layer of the outside walls. ... Now I have some nice R-38 walls with an ideal moisture barrier location and a separate air space about 1/2 inch thick in my walls.

Hey Oldman47, looks like you did a super job, but you built this for yourself. And acting (competently) as GC probably saved you another 20%.

If you were doing this as a full-time business, trying to feed your family and set up a nest-egg to send the fruit of your loins to collage, that house would probably remain a dream. Just not enough buyers.

I read somewhere: "BUILDING CODE: Minimum acceptable construction allowable for human habitation."

You definitely went above that.

 

[DickRussell]

Here are two diagrams of the double wall construction of my house, one where half the upper level floor rests on the foundation wall on the uphill side and the other where the upper and lower floors meet on the downhill side. On the first, the rim board is insulated as part of the wall cavity, with dense-packed cellulose. On the second, the rim board is insulated as part of the lower level wall cavity; the lower floor walls there rest on the frost wall (fully walkout there). In general, going superinsulated vs "code" costs on the order of 5% more (YMMV). I asked the framing crew how long extra it took them to frame the inner walls (done after the outer walls were up on each level). They thought around a day and a half. The extra studs cost around an extra grand. But I agree with others that getting a house done this way is really up to the buyer having the work done. Most folks don't know, don't care, don't want to do either. And that quote about "code" being minimum acceptable is just that. One builder on another site (jlconline, I think) has it in his tag line. "Code is the minimum to pass the test. You build to code, congratulations; you're grade is a D-"

PS: How do I get the two diagrams to show in-line?

 

[vinny11950]

Nice walls. I am jealous. Thanks for sharing the designs. XPS on either side of the foundation is nice too.

How big is the gap between the two walls?

 

[DickRussell]

How big is the gap between the two walls?

Gap is 3", which puts the cavity at 12" wide. Center-of-cavity is about R-43, whole-wall with framing figured in is around R-39. I roughed out the difference in whole-wall R for studs lined up vs staggered studs at perhaps a couple percent - not worth the complication and adjustments around windows, in my mind. In-line studs certainly made it easier for the framers to duplicate the outer wall in 2x4s for the inner wall.

 

[Oldman47]

In my case I just built the double wall system on top of the standard subfloor. That means the outer walls continue straight up from the rim joist just like any typical construction and the inner walls are supported a half inch from the outer walls by the floor joists and subfloor. This is a much less aggressive approach than the ones in DickRussell's diagrams but it worked for me. The way I tied the inner to the outer walls was by framing each window or door opening completely around with 1/2 inch ply. I knew that the wall with a half inch spacing would measure 5.5+3.5+.5 inches so I cut a piece of ply at 9.5 inches wide to fit the window space plus 2 2x4s long. The 2 2x4s are what I did around every opening so that I could use standard windows instead of windows custom designed to fit a super thick wall. What I ended up with is a window that fits just like it is mounted in a standard 2x4 wall but it is recessed into the wall as viewed from the inside. By boxing it with 2 2x4s I have room to surround that window on 3 sides with standard casings and I can do as I intend to and put a nice wide sill on every window without really intruding into the house. The spacers I use to fit that sill to the bottom of the window is something I will try to settle with my spouse before I start. She seems to think it would be nice to have a storage space under each window sill with easy access for things like Christmas decorations for each window stored right under it. We shall see.
My last tie between inner and outer wall was when the 2 walls were already in place. To prevent critters taking up residence between those walls I nailed wood across the top of all wall spaces to both block the critters and tie the walls together as they already are so they become more or less a single wall at the top and the bottom with that protection from shifting in the middle at each window or door. I was able to do that because I had specified special "energy heel" trusses for thick insulation and there was room to get my nail gun into that space. I intentionally paid no attention to lining up inner and outer wall studs because I really did not want them lined up and leaking heat. My outer wall studs were spaced to optimize the OSB sheeting and the inner walls were set up for economic use of drywall. That virtually guaranteed the studs would not align between inner and outer walls.
As CaptSpiff said, this construction would be a loser for a contractor working on spec, but this is my home so I pay myself to add the features that I want. I wanted some solid wall insulation and got it. My wife wanted wide window sills and got them. It is a win-win for me. Designing to allow thick walls does require that you look at every door and make sure it will still work without ripping out the hinges. I had to change a few things on my original plans to work better with thick walls but the changes were minor.

 

[Lake Girl]

Exactly, "penny wise and pound foolish."

Looking at the windows a little closer shows the flashing detail to be wrong. I guess if they overlap the moisture barrier over the tape on the top of the window frame it will work, but I thought the moisture barrier gets tucked into the window frame and then the window is installed.

When we replaced windows in our condo, we used a self-adhesive rubberized membrane that sealed from the moisture barrier over the framing members to the vapour barrier inside. Windows installed with nailing fins and then another layer of the rubberized membrane over the nailing fins sealed to the moisture barrier again. Contractor mentioned we were the only ones in the unit that had properly sealed windows

 

[Lake Girl]

The DensGlass is pretty interesting stuff ... looks like additional insulation would have to be on the interior though. Wonder if it is standard insulation w/vapour barrier or foam?
file:///C:/Users/Acer/Downloads/102250.pdf

When I first started reading it, I thought gypsum are you crazy? Fiberglass mat exteriors does reduce the potential for mold development. Wonder what they are using in the actual gypsum mix?

 

[sportbikerider78]

Some people need cheap homes. I would rather spend money up front and get an energy effecient home, but some don't have the money.

I don't think changing codes to something more aggressive is the answer. Changing how we build in the first place is what needs to happen in my mind. Isn't it a little ridiculous that we still live in mud and stick homes? With all the advances in materials, we still have very basic living structures.