BHM Forum      
Subscribe to Backwoods Home Magazine print or Kindle editions
Office Hours Momday - Friday  8 am - 5 pm Pacific 1-800-835-2418

Facebook   YouTube   Twitter
Follow Us!



 
Backwoods Home Magazine, self-reliance, homesteading, off-grid

Features
 Home Page
 Current Issue
 Article Index
 Author Index
 Previous Issues
 Newsletter
 Letters
 Humor
 Free Stuff
 Recipes
 Print Classifieds

General Store
 Ordering Info
 Subscriptions
 Kindle Subscriptions
 ePublications
 Anthologies
 Books
 Back Issues
 Help Yourself
 All Specials
 Classified Ad

Advertise
 Web Site Ads
 Magazine Ads

BHM Blogs
 Massad Ayoob
 Ask Jackie Clay
 Claire Wolfe
 Where We Live
 Dave on Twitter
Retired Blogs
 Behind The Scenes
 Oliver Del Signore
 David Lee
 Energy Questions
 Bramblestitches

Quick Links
 Home Energy Info
 Jackie Clay
 Ask Jackie Online
 Dave Duffy
 Massad Ayoob
 John Silveira
 Claire Wolfe

Forum / Chat
 Forum/Chat Info
 Enter Forum
 Lost Password

More Features
 Meet The Staff
 Contact Us/
 Change of Address
 Write For BHM
 Privacy Policy

Retired Features
 Country Moments
 Feedback
 Links
 Radio Show





  
 

BHM's Homesteading & Self-Reliance Forum
Posting requires Registration and the use of Cookies-enabled browser.

  Who's In The Chat Room

Go Back   BHM Forum > Homesteading > Energy

Energy Energy topics that do not have a dedicated board.

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 03-06-2012, 08:43 PM
alabamaman Male alabamaman is offline
New Member
 
Join Date: Oct 2011
Posts: 3
Question Concrete Home in Alabama - Good Idea?

Admittedly, I am nervous about posting this but I have been lurking for a while and there are some pretty smart people on this forum. So, I thought I would get an opinion.

I'm about to pull the trigger on my new home and I want to make it as energy efficient as I can and yet retain the 'conventional' look. (i.e. It won't be underground or circular or built out of shipping containers.) My original idea beginning 3-4 years ago was to build a dry-stacked block home and I still really like that idea for 3 reasons: sturdiness, thermal mass and ease of labor.

I'm planning to rebar and pour concrete into the cores of the block for mass and sturdiness. (I may be fooling myself on the ease of labor.)

Now, I'm no engineer but when I think of thermal mass I think of it as "the ability for a structure to store a temperature". (I've used this document as a reference. http://www.yourhome.gov.au/technical/fs49.html) That is, once this structure is a specific temperature, it will be difficult to change it.

My main concern is this: the Alabama summers are HOT - 90-100 degrees for at least 2 months out of the year. Will my home resist that temperature? If not, once my concrete structure is heated that hot will it ever cool down? (The nights are sometimes in the mid 80s) What can I do to be sure that I can keep it cool?

It makes no sense to do this if I'm going to be fighting it the whole summer. I need to be able to easily keep the temperature in the low to mid 70s for maximum comfort. I understand that in winter the structure will store heat alot better due to radiant heat from the sun, etc. But am I going to be baking in summer?

Some of you that built a concrete home - or someone that is smarter than me - can you help me out?
Reply With Quote

  #2  
Old 03-06-2012, 09:34 PM
kfander Male kfander is offline
Grand Master Pontificator
 
Join Date: Apr 2011
Location: Millinocket & St. Agatha, Maine
Posts: 1,947
Default

A friend of mine built a two-story home using rebar and poured concrete. This was in Los Fresnos, Texas, which is just north of Brownsville, in the Rio Grande Valley of Texas, where summer temperatures exceed those that you're speaking of.

I can't help you with ideas on the construction of the building because I didn't help to build it, but I do know that he was not a professional builder, but a paramedic, as I was at the time.

I have been in his home many times and the concrete construction kept the house comfortably cool in the heat and easy to heat on the rare cool days that we had.
__________________
That's my opinion and I'm sticking with it unless someone yells at me or something.
Reply With Quote
  #3  
Old 03-06-2012, 09:52 PM
MooseToo MooseToo is offline
Grand Master Pontificator
 
Join Date: Jul 2001
Location: south central ky
Posts: 5,931
Default

allow me to state the obvious even if it seems silly - in the construction you suggest (stacked and stuccoed and core filled) the concrete heat bank stays inside and your insulation (which is very much required) stays outside -
Reply With Quote
  #4  
Old 03-06-2012, 10:35 PM
Westcliffe01 Male Westcliffe01 is offline
Member
 
Join Date: Oct 2007
Posts: 237
Default

Ideally, use rigid foam insulation on the outside of the block. If you want furring strips for siding, perhaps spray foam is the best. The biggest problem with this type of construction is the details. The flashing where the siding ends to the foundation to prevent rodent access into the insulation. How to construct the windowsills, given the different layers of material from inside to outside.

You certainly need reinforcing, but it also has to be done right. The reinforcing has to be as close to the surface of the block as possible. Stuck down the center of the core it is virtually worthless. In countries where block is common, the rebar is always doubled spaced by "rungs" of 1/4" wire that hold the bar at the maximum distance apart for the block in use. The horizontal rebar is actually spaced so that it sits under the middle of the concrete in the block above, one on each side. The verticals have to be able to fit in the cavities, but are also oriented so that the "rungs" are perpendicular to the line of the wall.

There is also "face bonding" instead of re-bar. Face bonding uses very strong cement with fiber reinforcing so the reinforcement is spread over the entire surface. This is apparently stronger than regular core reinforcement and is what is used by default with dry stacking.

Something one does not see here, but I don't know why is the use of block or brick for all internal walls. By tying internal and external walls together the home is structurally far superior. If a tornado takes the roof off, such a home will typically stay together. It does mean that careful planning is needed for all plumbing and electrical work, so that it goes in as the walls go up. One does not build the walls and then think about where to run wiring or plumbing... it is also not quite as easy to renovate in future, but the acoustic quality of the home is very different. One can barely hear what is going on in the room next door.

I think it goes without saying that such homes have a slab foundation, with footings under where the internals walls will run so that it is all fully load bearing.
Reply With Quote
  #5  
Old 03-06-2012, 11:04 PM
MooseToo MooseToo is offline
Grand Master Pontificator
 
Join Date: Jul 2001
Location: south central ky
Posts: 5,931
Default

Quote:
Originally Posted by Westcliffe01 View Post

There is also "face bonding" instead of re-bar. Face bonding uses very strong cement with fiber reinforcing so the reinforcement is spread over the entire surface. This is apparently stronger than regular core reinforcement and is what is used by default with dry stacking.
quite often with dry-stacking, surface bonding is utilized in conjunction with core reinforcement and not instead of it -

your idea of load-bearing walls continued into the interior is excellent -
Reply With Quote
  #6  
Old 03-07-2012, 04:40 PM
Dennis G Male Dennis G is offline
Senior Member
 
Join Date: Sep 2010
Posts: 377
Default

Quote:
Originally Posted by MooseToo View Post
quite often with dry-stacking, surface bonding is utilized in conjunction with core reinforcement and not instead of it -

your idea of load-bearing walls continued into the interior is excellent -

here is a system...

http://www.arxx.com/Content/Home-Own...-It-Works.html

talk to them, YOU might be able to use their system, or one like it...do some research...

I plan to build my house with this system or one like it... keeps in the heat or keeps out the heat... plus will stand up to high winds...

Easy to run conduits and piping in the insulated parts inside, plus you can put sheet rock on the inside, will look like most houses...

Costs might force you to abandon this system, but worth looking into it.

Dennis G

Dennis G
Reply With Quote
  #7  
Old 03-07-2012, 07:01 PM
Faith123 Female Faith123 is offline
Member
 
Join Date: Jan 2012
Location: Illinois/UP Michigan
Posts: 221
Default

You may want to look into ICF (Insulated concrete forms) too. (I can't get the link in the previous post to open....that may be what is suggested there.) They are insulated on both sides, so the concrete acts as less of a heat sink. There you have your sturdiness and ease of labor, but may not retain the heat that a block wall would.

We have a 900 sq ft place with block walls. In the dead of winter it takes a bit for the place to warm up, but once it does we can leave for the day and let the stove burn out, and it stays quite toasty inside because the block retains so much heat. It is built on sand, we think the foundation may have been hand poured. It is quite shifty. Don't skimp on the footings.

I know you are going for a traditional look, but if you managed a north facing structure with an earth wall on the south side, that would help a lot. And a white roof.
Reply With Quote
  #8  
Old 03-07-2012, 07:29 PM
kammisue kammisue is offline
Senior Member
 
Join Date: Jan 2012
Posts: 273
Default

I know nothing of building... but I can tell you that that style of building is really popular in my area (Southeast Alabama Barbour/Dale counties) and the folks I know that live in them aren't unhappy/complaining about anything..
A friend of mine moved into hers about 2 years ago... she did a stucco finish and it looks very old world...
Good Luck
__________________
[FONT=Courier New][SIZE=3][COLOR=blue][B][I][SIGPIC][/SIGPIC]Whosoever denieth the Son, the same hath not the Father; [but] he that acknowledgeth the Son hath the Father also. I John 2:23[/I][/B][/COLOR][/SIZE][/FONT]
[B][I][FONT=Courier New][SIZE=3][COLOR=purple]Y Gwir erbyn y Byd[/COLOR][/SIZE][/FONT][/I][/B]
Reply With Quote
  #9  
Old 03-07-2012, 08:25 PM
MNfarmlady Female MNfarmlady is offline
Member
 
Join Date: Nov 2011
Location: SE Minnesota
Posts: 33
Default

Our house is built out of the Integrated Concrete Forms and we love it. The foam blocks stack together like Legos, the rebar is positioned in the middle, and then concrete pumped in. The insulation factor is phenomenal. You can then side it with whatever you wish on the outside and put whatever you wish on the inner walls. We used cedar log siding outside and tongue and groove pine on the inside.
Also they are very sturdy. Our house was hit by a mudslide. Had a foot of mud inside, and probably 8 feet of mud hit the side wall. The house stood strong, I think if we had been in a stick-built house we would be dead. The only reason the mud got inside was because a tree knocked the door open.
I would recommend this type of concrete house to anyone.
Anne
Reply With Quote
  #10  
Old 03-07-2012, 08:38 PM
DavidOH's Avatar
DavidOH Male DavidOH is offline
Grand Master Pontificator
 
Join Date: Jul 2001
Location: Central, OH
Posts: 2,175
Default These folks have a nice place

This is a blog about a couple building their home.
It is earth sheltered.
She has posted it here before, but I could not find it.

This link is to their website:
http://www.city-data.com/forum/tenne...tennessee.html

Going Off Grid in East Tennessee

You may find it very useful to read how they did it.
There are LOTS of pages replies and Photos.
You my even find some posts from people here.
Reply With Quote
  #11  
Old 03-07-2012, 11:50 PM
Dennis G Male Dennis G is offline
Senior Member
 
Join Date: Sep 2010
Posts: 377
Default try this site

http://www.wisehomedesign.com/icf-homes.html

What are the advantages and disadvantages of ICF homes?

ICF homes provide a solid solution to high energy costs and extreme weather.
There are advantages and disadvantages of ICF homes, so educate yourself before making a final decision.
Reply With Quote
  #12  
Old 03-08-2012, 11:06 AM
alabamaman Male alabamaman is offline
New Member
 
Join Date: Oct 2011
Posts: 3
Default Interior Walls too

Even though the plans I've been looking at are mainly open floor plans. I had thought about making some of the interior walls concrete as well to add to the strength of the structure and, as was mentioned, cut down on noise. I also figure that a solid interior wall would retain the heat (temp) of the interior better and help to radiate it over time.

I'm not sure what to do about electrical wiring. I had originally believed I would put furring strips (sideways 2x4s) on the inside of the home and drywall as normal. But that makes very little sense in terms of enjoying the benefits of the thermal mass on the inside. So, I've got to figure out my plan for the electrical wiring on the exterior walls.

As for insulating/sealing the outside I've had many thoughts. I actually hadn't thought about insulating the outside too much but that seems so obvious now that it's been mentioned to me. Not sure how I would approach it. I had actually wanted a stucco over rock exterior and had considered using the surface bonding cement and covering it with something. I've actually talked to Line-X about covering the house with tan-colored bed-liner material. ($17K for plain 2000sq ft house btw) And I've seen the textured deck sealing stuff at Home Depot that is supposedly water-tight and has some nice colors as well. (I may still use it on the inside. It looks really nice.)

Thanks for the input.

If anyone else has any comments I'd love to hear them.
Reply With Quote
  #13  
Old 03-08-2012, 01:34 PM
Faith123 Female Faith123 is offline
Member
 
Join Date: Jan 2012
Location: Illinois/UP Michigan
Posts: 221
Default

Something else to consider since you are using block/concrete is to build a safe room. An interior room or corner room with no windows and block walls all the way around and a sturdy door and hefty ceiling for a tornado shelter. It could be a pantry or bathroom.
Reply With Quote
  #14  
Old 03-09-2012, 12:34 AM
Westcliffe01 Male Westcliffe01 is offline
Member
 
Join Date: Oct 2007
Posts: 237
Default

Wiring does not have to be a big issue. Pre-plan where you want the outlets. The easiest way is if you do not fill the cores until you pour a bond beam at the top of the wall. If you go that way, you use electrical conduit that runs along the top of every wall distributing the electrical power from the switchboard. Then you cut/knock out the openings for all of the electrical and cable outlets in the wall itself at the right height. Drop more conduit down the cavity to each location (means that one has to be neat with the mortar, if dry stacking, no such problem, or use thin set to hold the blocks in place before face bonding. Connect the electrical outlet boxes to the conduit and then tap in to the "distributor" pipe at the top of the wall.

Always try to provide for a means to add things later that one did not think of or were not available. Keep electrical, cable and phone separate. How many still have conventional phone hookups ? Run extra 230V power to a small distribution board in the garage. Even if not needed now, it will be great to have it when you find a reason for it later...
Reply With Quote
  #15  
Old 03-30-2012, 01:36 PM
alabamaman Male alabamaman is offline
New Member
 
Join Date: Oct 2011
Posts: 3
Smile Thanks everyone

I appreciate everyone that replied to this thread... After much deliberation (I've been researching this off and on for 3 years) I have decided to build a home with normal wood frame construction.

I've not found a builder that I feel can reliably support me in the other phases of construction if I decide to build this way and I'm not that confident in my own construction ability. Any mistakes would cost me dearly and I'm not in a financial position to recover from too many mistakes. So, I will go with standard construction on the exterior walls. My hope is to include some other energy saving factors such as radiant heat floors and heavy insulation to help reduce my energy needs (especially in winter).

Again, thanks for all the helpful comments.
Reply With Quote
Reply

Bookmarks


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -2. The time now is 09:03 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
© 1996 to Present. Backwoods Home Magazine, Inc.