New Home Begins

[tkappeler]

tkappeler:

Is the install manual online? Or does it come only after buying the panels?

PM sent.

 

[mjncad]

I'll be looking at the Ray-Core website. Although batt insulation is better than nothing; it is too easy to do a sloppy job installing the stuff and thereby defeat the purpose of insulation.

 

[edlegault]

I did a very quick calculation on the back of a napkin for a 2x6 wall with fiberglass bat (R-18) versus 2x4 Raycore panels (R-25). The 2x6 wall was a little bit less than $2 a square foot for 5.5 inches of fiberglass batt insulation (R-18). To get to about R-25 takes 2 inches of closed cell spray foam plus 3.5 inches of fiber glass batt for a little less than $4 a square foot. This puts the Raycore panels at a competitive price for the same R value of insulation.

 

[sdkubota]

This isn't really true. Curing at lower temperatures (and over a longer period of time) will result in higher concrete ultimate strength and less cracking. You want really want the concrete to cure over the longest period possible and at a uniform temperature (not fluctuating). So I would agree, it looks like this pour was under ideal conditions. Interestingly enough, I once saw a technical paper reporting on use of a concrete additive that prevented freezing so the concrete could be held below freezing during the cure. This increased the ultimate strength of the concrete.

If you want to challenge my facts at least have it correct. Concrete cylinders for checking compressive strength are stored in a water bath at 70 degrees F for 28 day design strength. Concrete pipe are cast and then placed under tarps with 100+ degree heat and 100% humidity. The reach their required strength and can be shipped after 24 hours of curing. Concrete continues to cure for 100+ years although approx. 80% of ultimate strength is achieved within 28 days given 70 degree temps and submerged in water. There is zero benefit to curing concrete at lower temperatures and all that happens is you ****** the curing process.

Calcium is added to concrete during low temperature pours which helps generate additional heat but actually weakens the concrete compressive strength. Concrete does not cure below 32 degrees.

 

[tkappeler]

More rain last night. But we were able to move another truckload of fill around the foundation. Only the front remains a pool at the foundation. We will have to work around the rain and the framers as I do not want to get in their way. We will take down the ramp that was built for the concrete trucks that went unusable and fill around the foundation with that. Of course, we have to pump out that water first.

In the meantime, the framers were able to get three wall sections up and the rain is holding off now, so they are busy. Here are picks of the progress. The pictures out to the yard are from various bedrooms.

We are so happy that we opted for the 6' tall windows instead of the 4'9", especially with 9' wall heights.

 

[EddieWalker]

We are so happy that we opted for the 6' tall windows instead of the 4'9", especially with 9' wall heights.

This is where I get confused. You have walls that will have an extreme R value, but you went with bigger windows that will have an R value of around 3. At what point does is it not advantagous to spend more money on increasing the R value of a wall when you lose so much in the windows?

Air sealing is the single most important thing you can do for a wall. I'm a HUGE supporter of that. Then maxing out the insulation in the attic is where you see the biggest return for your investment and energy savings. There is only so much you can get out of a wall that has a window in it.

Eddie

 

[tkappeler]

This is where I get confused. You have walls that will have an extreme R value, but you went with bigger windows that will have an R value of around 3. At what point does is it not advantagous to spend more money on increasing the R value of a wall when you lose so much in the windows?

Air sealing is the single most important thing you can do for a wall. I'm a HUGE supporter of that. Then maxing out the insulation in the attic is where you see the biggest return for your investment and energy savings. There is only so much you can get out of a wall that has a window in it.

Eddie

Eddie,

Building is always about compromises. We are being as energy efficient where we can, based on climate and expense. Some considerations, like wanting to have great views, are a higher priority than efficiency. We are still using Andersen windows with a U-factor of 0.30 and a SHGC of 0.21.

NJ adopted the IECC (International Energy Conservation Code) 2009 codes. All new homes must meet these standards. ResCheck is a free program that can demonstrate conformance to the standard. We ran it and are 18% higher than the minimum allowed by code, even with the larger windows.

 

[KennyG]

If you want to challenge my facts at least have it correct. Concrete cylinders for checking compressive strength are stored in a water bath at 70 degrees F for 28 day design strength. Concrete pipe are cast and then placed under tarps with 100+ degree heat and 100% humidity. The reach their required strength and can be shipped after 24 hours of curing. Concrete continues to cure for 100+ years although approx. 80% of ultimate strength is achieved within 28 days given 70 degree temps and submerged in water. There is zero benefit to curing concrete at lower temperatures and all that happens is you ****** the curing process.

Calcium is added to concrete during low temperature pours which helps generate additional heat but actually weakens the concrete compressive strength. Concrete does not cure below 32 degrees.

Test cylinders are kept at a constant temperature for consistency, not high strength. Sounds like the pipe process is customized for high production rates. Here is a reference providing results from the Portland Cement Association showing that the greatest long term strength results from curing at 55 degrees F or 40 degrees depending on the type of cement. They also found that even concrete cured below freezing was stronger than 73 degree cured concrete. Even that surprised me. Apparently they were able to cure the concrete below freezing.

Best Curing Temperatures - Cement, Concrete Curing, Curing Blankets - Concrete Construction

High temperature curing gives you an early strength gain (important when you are casting concrete and need to quickly remove forms and move the casts) at the expense of long term strength. See the charts in this summary:

Curing Concrete | Concrete Technology | Portland Cement Association (PCA)

You often see cautions about curing below 50 degrees, but that is a concern about normal daily fluctuations and, if you pour at below 50 it is likely it will dip below freezing before it cures. You are correct that chloride addition reduces long term strength. However, the paper I saw (and don't have now) used a different "antifreeze" that did not have the same effect as chloride.

 

[Depmandog]

DING DING DING

sdkubota and KennyG back to your prospective corners! This will be the last and final round. Debaters, protect your opinions at all times. Extra points will be given for verifiable references. Opinions only will be counted against you. Come out fact slinging at the sound of the bell.

DING

Debate!

Aw, just joshing. I am truly interested! I have a ballast box full of curing concrete in my (currently) unheated work shop - temps stay around 40 when I don't have a fire going. Poured it last Friday.

This little side jaunt has been informative

 

[mjncad]

As I recall, the Hoover Dam has cooling pipes in it that were placed for the sole purpose of controlling curing temperature due to the project location's climate and the amount of heat generated by so much concrete curing at one time.