Home flooring question (non-Valk... sorry...)

[CajunRider]

Google isn't being a friend right now... maybe I just have a very strange setup.    

So I have a house on piers.  Part of the house is wood flooring with standard wood seal beams & 2X6 joists.  The other part (small area) is a concrete slab on piers.  I've never seen this before buying this house.

The wood floors get a tad bit chilly in the winter, which is expected.  The concrete part, however, is downright brutal!!!  My feet literally start cramping if I don't have my shoes on!   

I've been told before that one should NOT insulate the bottom side of the wood flooring because it will hold moisture and cause rot... which I can understand.  Plus, like I said, the wood part isn't bad. 

However, can the under side of the concrete slab be insulated since it is off the ground without any issues??  I have about 2 1/2 feet of space between the under side of the concrete and the ground.  I'm thinking 2 or 3 inches of insulation under there will help the icy mid-night pee breaks... otherwise, I'm going to have to find some nice thick rugs.   

[hubcapsc]

Electric radiant floor heating!

I put it down under the tile in the bathroom, still works great...



-Mike

[MP]

Electric radiant floor heating!

I put it down under the tile in the bathroom, still works great...



-Mike

Yep.  Put the heat in, then thin coat, laying tile or more concrete on top.  Nice and warm.  And, to save money, go ahead and insulate the bottom of the concrete.  Just insulation alone will help with cost, but the floor will still be cold.Without heat, concrete is ALWAYS cold.

You could also put a little heat UNDER the wood flooring too, but, would need to leave open, or it will be wet. Just a little, to warm it a bit.  Too much will dry the wood out too much.

MP

[Crackerborn]

  to radiant heat, but do research to make sure you get a servicable variety. Some kinds will short out if knicked when laying substrate. If your slab is on piers, you are in a soft soil condition and pilings are sunk to prevent the foundation from shifting. You should have grade beams supporting the slab and insulation should be applied to all exposed concrete to cut energy loss. Generally grade beams on pilings are back filled before the slab is poured unless built to be above a flood level, say 8 feet in the air. Then it's called a stilt house.

[fudgie]

I wouldnt put fiberglass insul under the concrete but some 2" 4x8 foam board. Usually its blue or pink. I wouldnt know why you cant put fg insul under the wood floor. Put the fg insul and then some visqueen/plastic up and then cover it. That would hold out the moisture.

[Jess Tolbirt]

i was thinking about putting a coat of something like great stuff on it and put enough on it to let it swell up to about 4 inches, that stuff will stick to the bottom,, heck that stuff sticks to everything,, you can buy it in those big containers..

[CajunRider]

If your slab is on piers, you are in a soft soil condition and pilings are sunk to prevent the foundation from shifting. You should have grade beams supporting the slab and insulation should be applied to all exposed concrete to cut energy loss. Generally grade beams on pilings are back filled before the slab is poured unless built to be above a flood level, say 8 feet in the air. Then it's called a stilt house.

Close... 2.5 ft in the air, without any sort of beam under the concrete.  Just a hand-full of piers (stilts) holding a 4" thick slab of concrete 2.5 feet in the air.  

But this is only about 400 sq ft of the house.  The rest of the house is the typical wooden beam & joist type flooring which doesn't get near as cold.  

Like such:  

Would this be a "Stilt House"??

[fudgie]

Or just have the insulators put 4" of spray foam under the whole house.

[Hoovey]

I second the spray foam suggestion. It shouldn't take much and it should be closed cell foam!! Not only to insulate  but the foam will stop any air infiltration you might have.

[Pete]

You can insulate either floor. With what ever you want to BUT:
The important point is to have a moisture barrier on the side where the MOST moisture is located.
In your case the ground.

I would also suggest that good airflow between the ground and the moisture barrier would be a GOOD thing.

And good drainage of the ground under the house would be a BIG plus.

[Gryphon Rider]

+1 on the spray foam under both types of floor.  Ask homeowners who have had this done how thick their foam is and their satisfaction with it.

[Tundra]

Mike there is a dog hiding in your tub.

Electric radiant floor heating!

I put it down under the tile in the bathroom, still works great...



-Mike

[JimmyG]

+1 on the spray foam under both types of floor.  Ask homeowners who have had this done how thick their foam is and their satisfaction with it.

I have used it in my house and plan to use more, in a situation like you have.  Unbelievable how well it insulates. Made a believer out of me. My application was about 5" of foam. Moisture barrier on ground, not wood or you will surely see it rot. I have seen this done wrong and also right. Just get your research done and you will be surprised what a difference it makes.  You can also buy the stuff yourself and apply it and save quite a bit of money.

[Crackerborn]

You have a house on piers, probably built long before the local governing body had any silly building codes or failed builders hired by said body to try to enforce such codes. Typical of the southern construction methods used into the 60's. No hurricane straps, no steel clips, just nails and local wood (although someone added concrete on yours). I helped remodeled a similar home in Delray Beach, FL that was built in the 20's out of Dade County Pine (can you say lighter pine) and withstood every wind storm that blew up the coast including the 1939 hurricane that leveled Palm Beach. To add a large deck to the pool area, the architect said we needed 32 pilings sunk to the bedrock every 6 feet. The piers raised that house 30 inches above grade and a better haven for spiders, scorpions, cockroaches, lizards, and even a racoon or two would be hard to find. Just ask me how I know, since the youngest on the site were usually given the more  colorful jobs such as removing all ball and tube electric from the underbelly. 

And yes to foam professionally applied.