Concrete Block (Cinder Blocks)

[stevenf]

I've posted twice and so far ya'll have scared me off both. The first was using RR ties for piers and the second was using sonotube. The RR ties because you couldn't cut well, they might have termites and they rot from inside out quickly stood on end. And the sonotube requires as much as 22,000 lbs of concrete which I don't believe I can mix in a wheelbarrow.
Here's the hopefully my last idea how about using Concrete Blocks (Cinder Blocks) the house plans I've drawn are 28' x 60' it would require 7 piers long by 3 piers wide with two extra on the ends. Which means I need 25 piers the idea is to stack 2 on 2 on2 on2 to give me 32" of height and 16" square crisssrossed two one way two the other etc. and then filled with concrete and rebar scratched in to the earth to level but essentially sitting on top of the ground. I'm in South Texas so frost is not a consideration and the house site is fairly level and virgin caliche and dirt.
Has anyone in the Southern States used this method and how did it work out. I have found that most mobil homes in this area are done like this, do you think I could use this same method for a stick built house.

 

[Bird]

<font color="blue">( most mobil homes in this area are done like this )</font>

Yes, they are, but without the blocks having rebar and being concrete filled, and instead of the blocks being directly on the ground, a solid concrete, square "pad" is used for the bottom of each pier, with a board on top of the concrete blocks between the top blocks and the trailer frame. And frequent re-leveling is necessary in many places due to the natural contraction and expansion of our surface soil. Minor adjustments are usually made with hardwood wedges. Then a number of anchors are augered into the ground around the perimeter with metal straps to hold the entire unit down.

<font color="blue">( do you think I could use this same method for a stick built house )</font>

Yes, you could, but I would not recommend it. The mobile homes (or manufactured housing) are built in a factory on a fairly rigid steel frame, transported to the site, and then the piers are placed under them. In addition to the piers under the frame, "perimeter blocking" is also required. That amounts to two piers under the edge of the house at each door as a minimum; additional perimeter blocking is necessary on some of the bigger units such as the 18' single wides. To do as you say, you would need to get your piers set and leveled, then build on top of them. I would be surprised if you didn't have uneven settling of those piers even during construction. My next thought is that I believe (could be wrong) you have grossly underestimated the number of piers that would be required. While I don't have an exact number right now, look under a double wide mobile home of that size. There will be 4 rows instead of 3 (two frame rails for each half of the house), plus the perimeter blocking, and while I don't remember the distance between piers right now, I believe my 28' x 52' double wide had more piers than the 25 you mentioned.

So, yes, you can do it, but I don't think you'll like it. /forums/images/graemlins/wink.gif And since I'm no construction expert, this is purely my personal opinion. /forums/images/graemlins/tongue.gif

P.S. I just looked at a new 16' single wide that was set up in the park this morning; not sure of the length, but think it's either a 66' or a '70 one and it has 32 of those piers under it.

 

[dbelisle]

Seven piers on each row for a total of 21 piers sounds like it would work as long as you build a carring timber on each set of piers. Being over a twelve foot span you will need at least 2 x 10 on your floor system.

I would go back to the sono tubes before I would set a house on blocks. You want to start with a good foundation or you will regret it later. Why not rough your utilities into the ground and pour a concrete slab. It would cost less that a deck system and make a great base to start your house.

Up here in New England, we even have to pour a concrete pad before we can even start to set a double wide mobil home.

Dave in NH

 

[GareyD]

Back about 30 years ago, during the "back to nature" peace, love, dope phase of my life...several of my friends and I (can you say / do you remember communes?) purchased 30 acres and jointly built houses for each of us, using much the same methods you are asking about...

We built some on flagstone and some on cinder block a total of 8 houses and several smokehouses, outbuildings and barns...when I visited a year ago, all except 1 are still standing...the one that wasn't was a result of a direct hit by a tornado...

Since I'm thinking about building a guest house on my current place...here are some things I'll do this time...

1. Pour a 3' square footer on grade...four 8' rebar driven from the centers toward the outsides, then bent up to pass throught the blocks in the piers..add extra rebar if it looks neccessary...

2. Bed the bottom blocks to the footer...dry stack to height and bend the rebar at the top to center/anchor into the top block...pour full of 'crete add the anchor/sill bolts and scree the top...

3. Flash the top of the pier with a sheet metal pan turned upside down...and treat or have treated around the footer for termites...

4. Have 2 piers at any exterior doorway (helps to keep the door swinging freely in years to come)...and piers down the long center of the building...

My neighbor and I built a 12' wide wrap around porch all four sides of the house this way when we built his house 8 years ago...the only reason we didn't do the house this way, was he wanted a full basement....still as plumb today as the day we finished /forums/images/graemlins/smile.gif

Of course, you will have to get this past your local zoning ****'s...around here we don't have that problem...yet /forums/images/graemlins/crazy.gif

YMMV
GareyD

 

[texbaylea]

It has been a while since I was in Boerne but you are west of the Balcones fault zone which means you do not have the alluvial soils with their high clay content. Houses have been built on block foundations succcessfully for years. Slabs are a quick and dirty substitute.

I would go with dug and poured footers then add the block piers. Just be sure that everything is tied together with rebar and that your sills are also tied down. I built a house between Houston and Galveston in 1970 on "bell bottom" poured piers. It never moved even during a flood in 1979.

I did not read your post about sonotube but I will go back and do so. Houses with framed floors are, in my opinion, the better way to build.

Vernon

 

[stevenf]

I thought the number of piers seemed light also but on the 28' dimension the piers are 16" x 3piers = 48" = 4' so 28' minus the 4' is 24' divided by 2 is only 12' span between piers. It is still early so my math is probably off somewhere but even so I have to have the center wall support beam for the roof rafter support and it just seemed like way overkill to run another set of piers between the center and the outside set and have cut the span to less than 6'. I'm really sounding this off ya'll so feel free to open up and let me have it I know that a solid foundation would be best and than sonotubes drilled in would be next choice since this is sorta a temp fix for us I hope, doesn't it seem like it will work fine. Someone mentioned using 2 x 10 floor system which I think would probably be best but anybody that has suggestions please feel free I can use all I can get at this point.
I just have to add this about halfway thru this post one of my hunters came whizzing up on his 4wheeler he had a very nice 10pt white-tailed buck strapped across his rack and a big smile. Thank God its the first one of the season and the hunters had already started grumbling about their less than successful first weekend.

 

[texbaylea]

The house I built in 1970 was roughly 80' x 40' and had 40 12" piers with 30" bottoms and 2 18" piers with 36" bottoms for the fireplace. 4" x 10" sills supported 12' o.c. with 2 x 10 joists 24" o.c. with 1-1/8" tongue and groove plywood sub floor would be adequate. If you put in the loft make those piers larger so that the supporting columns bear directly on the piers and the sills can butt against the columns with good ties.

I also do all of my framing work now with 3'' square drive screws and all plywood or other sheathing is also glued. Also look at engineered wood sills and joists. Always straight and uniform.


Vernon

 

[Cliff_Johns]

</font><font color="blue" class="small">( I also do all of my framing work now with 3'' square drive screws)</font>

I was under the impression that screws were inappropriate for framing because they are considerably too brittle, breaking instead of just giving a little when the wind really blows. I thought I'd read that in Fine Homebuilding. Could be that screws have changed some, but it seems to me that nails are a perfect fastener for framing and that even if nails were more expensive, they would still be a better choice.

Cliff

 

[texbaylea]

You are correct where builders use drywall screws, I use screws from McFeely's so I know the strength. Nails will work out from thermal cycling, screws will not.

Check them out www.mcfeelys.com .

Vernon