2x6 or 2x4 walls?

[JRobyn]

Hi folks,

We're starting to gather plans for the house at the farm, and one of our first decisions is to go with either 2x6 or 2x4 for exterior wall framing. This is for middle TN, where there are typically not weather extremes, nor severe wind loads, so I'm not really convinced that the extra cost of the 2x6 framing is justified. Anyone have any good metrics regarding the cost difference and other pros or cons?

- Jay

 

[Richard]

I'm not an expert (by ANY stretch) but... I've heard of using 2x6's where you want to help isolate sound transmission from room X through the walls to room Y.

So, if you're going to do a home theater, you might consider using something like that to help isolate that room from the rest of the house.

As for using it on outside walls, I suppose one could put thicker insulation in there?

Would also give you more room inside the walls for wiring & stuff? (though I guess that's not a major problem anyway?)

The next house that we build WILL have a "sound room" and I'll do everything I can do, at least to that room, to help isolate it from the rest of the house.

Having two monster speakers (see avatar ) in my house is one thing but if I can have it MY way, our next house will have 5 of those in a HT room and it WILL be something to die for!!

 

[ByronBob]

Normally homes in the north are 2x6 on the outside for insulation purposes and 2x4 in the inside walls. I added insulation in the inside for noise purposes and not give the walls the "hollow" sound you get when empty.

The cost really might only be a hundred bucks more for the exterior and it's worth it for structure strength and noise help.

 

[scott_vt]

Afternoon Jay,
Other than what others have added about insulation, another nice feature of 2x6 exterior walls is you can have a nice sized window saddle. They are just great for letting your wife have a showplace for all her nicknacks ! They also look nicer IMO !

 

[AlanB]

For me, here in Clarksville TN, the easy to get, ready to use, available at Lowes, HD etc stuff is geared around the 2 X 4 wall. If you go with the 2X6 there will be a bit more trimming and hunting for stuff. Not a big deal, but something to consider.

I like going with the "standards" usually.

And yes, it is all available just not quite as readilly as the 2 x 4 stuff.

 

[Jimbrown]

2x6 for strength and the insulation. No one here builds 2x4 except the guys doing the cheapo build it yourself stuff. All the builders go 2x6.

 

[Egon]

Check your codes. There are some places where 6 in. walls are mandatory.

 

[MrJimi]

I'll would also go with the 2 X 6 walls in todays times, stuff them with insulation and kick back and enjoy your effort on doing it right the first time, at my age I will not be able to build/or have a home built but I would go with the 2 X 6 walls and maybe some inside
It will cost you one time and you will save till ?
do it
Jim

 

[dmccarty]

Jay,

When we built the house we put in 2x6 walls which allowed for more insulation. Origionally we wanted to use ICF's but I knew we where going to put in lots of big windows. Kinda hard to justify the added expense of ICFs when all major rooms are going to have at least one window 6x8. So we compromised and put in 2x6 walls. And this may have been a waste. I think the 2x6 walls allowed us to put in R19ish insulation plus we have one inch of foam on the sheathing which gives us a wall R value of around 25.

The attic is about R40 and is where most energy loss occurs.

The 2x6s are stronger so if a tree hits the house maybe it will help. And the thicker insulation does deaden outside noise.

There is a program called RESFEN that will tell you how much the windows package in the house will cost to heating/cooling the structure. Seems like I had another program that would look at the costs for different R values. There are a bunch of free software out there to do this kind of analysis. Hopefully the RESFEN site will be a good starting point. RESFEN : Software : Resources : Environmental Energy Technologies Division

By the way the numbers produced by RESFEN where danged close to what it costs to cool the house. Since we heat with wood its hard to verify the programs number but the heating cost looks like its in the ball park.

Later,
Dan

 

[George2615]

I'm with the majority on using 2x6es for exterior walls. More space for insulation. You may not need it during winter but more insulation will cut your cooling bills as well and better sound dampening. 2x6 inside walls I'd doubt you'd need.

 

[Mickey_Fx]

Code requirements aside, I'd recommend you spend a couple hrs and do a little math, cost Vs benefit analysis. Cost of added materials today, lumber and insulation Vs reduced energy costs. Don't forget to include likely increases in energy costs over the yrs and the possibility of some tax credits for being more energy efficient. If the payoff on the added cost is less than 10 yrs, I'd go for the added cost today.

You should be able to get most of the info needed for this little exersize from the lumbr yard and power Co(s).

 

[Diesel-ME]

Jay,

Code considerations not withstanding.....You might want to consider 2x4 if you use a high R-value insulation such as sprayed on foam. You would yield R-24 or so with foamed-in 2x4 walls. You would have a nice tight easy to heat/cool house. If you go that route install and air exchange system too, else you'll be breathing stale air all the time.

~paul

 

[JasonL]

I am a framer of high end custom homes. My opinion (for what its worth) is to use spray foam and 2x4 walls. That is if you are having 8' or 9' ceilings. We do a lot of 10' ceilings, and I would use 2x6 there for strength. I question just how much advantage you actually get with conventional batt insulation going to 2x6. I know it says the R value is higher (and it is) but the weak link is still there -AIR MOVEMENT!!

Jason

 

[JRobyn]

Thanks for the input!

For sound considerations, the area we are in is extremely quiet, and if there *IS* any significant noise outside, I probably want to know about it!

There are very, very few code requirements in this area; they've only recently added septic and electrical permitting, so it's not likley that any code would require 6".

I really like the extra strength consideration, and the ability to go with R-19 insulation. Like Dan, we'll also have lots of glass area, so the extra insulation to help offset that might be the deciding factor.

We have a probable GC/builder in mind (just finished my BILs house), so I'll check with him regarding cost differential, both for materials and for framing labor. I can't see where additional labor would be much of a factor, but with the ever-increasing cost of lumber, 2x6 cost may be a significant factor. Anyone have any recent data on cost difference that I can cross-check against the builder?

- Jay

 

['Bota Fan]

I sure wouldn't count on a lack of wind in your area. Tornadoes and severe thunderstorms can pop up anywhere. We used 2 X 6 walls with brick on top of that for all of the reasons others have stated. No regrets. Can't imagine you'd be unhappy with six inch walls. Four inch? Maybe.

 

[ericinmich]

We built two years ago and the 10' and over walls are 2x6s. We could of upgraded them all, but our builder talked us out of it. As most (75%?) of the heat loss is up, the walls are a small part. Then if you realize that the windows are the weak link in heat loss to the sides, then the R values of the walls has a very small impact. I ran the numbers (with very large SWAGs) and it wasn't worth the extra for 2x6s.

But what do I know...

 

[N80]

When I built my log cabin I used mostly 2x4 framing for interior walls but used 2x6 framing on walls that had plumbing in them. Just made it easier.

 

[gotcha]

Check your codes. There are some places where 6 in. walls are mandatory.

The above is the very first thing one does before designing and/or laying out a home or any other type of wooden building.
Most areas are now requiring you to use 2X6 outside wall framing for all energy savings. All parts such as door, windows and other parts are now made and easy to get for both the 2X4 and 2X6 walls. The initial costs are a bit higher, but the savings makes up for it in a very short time. Pay back is around 5 years and from there on it's all savings. Don't forget to go with the double insulated windows and doors. Again in most areas this is also required by code. As stated in the thread below about using 2X6's on interior wet walls is also the most common thing to do.
The Gotcha Man

 

[dmccarty]

Jay,

I forgot to mention we have 10' ceilings. Helps in the summer but hurts in the winter.

I highly recommend the books by Joe lstiburek. He is an engineer who has books with design details depending on one's climate. He has a website at Building Science Corporation

The wall details in our house are from one of his books.

Later,
Dan

 

[WayneB]

Around here it is code to go with 2x6 exterior walls. Just didn't know there were that many places where people are building 2x4 stick houses any more. Just not sure what the savings would be using the 2x4 wall structure.