[lti2000]

I need help to understand on flooring insulation.

I am ready to install a new solid hardwood floor over subfloor over crawl space cover with plywood. Even though I do have insulation under my subfloor/crawl space, I like to put an extra insulation layer between the plywood and the hardwood.

Can you suggest what kind of insulation material I can use? I have two type of radiant barrier sheets to question on:
1) Radiant barrier sheet (like in http://www.radiantbarrier.com/diamond-insulation.htm)
2) Double bubble radiant sheet (like in http://www.radiantbarrier.com/double-bubble-insulation.htm)

Please explain which type is better, if it is ok to use for the application, pros and cons of each if use, or better, any other recommendation.

Thank you in advance.

 

[joecaption]

Waste of time and money.
How did you insulate under the floor?
Make sure your location is in your profile.
If the crawl space has been air sealed and insulated that's all you need.
There's just no good way to get enough insulation and still be able to have a hard, solid, flat surface to attach the floor to and not have it effect the door openings, and baseboards.

 

[woodman58]

Try cork 1/4" underlatment. It atleast has an R value. I did not see an R-value on the 2 you mentioned.

http://www.ecobydesign.com/shop/cork/underlayment-specs.html

 

[lti2000]

Try cork 1/4" underlatment. It atleast has an R value. I did not see an R-value on the 2 you mentioned.

http://www.ecobydesign.com/shop/cork/underlayment-specs.html

It designed to reflect heat (i.e. keeps heat to go thru the floor with crawl space), thus, the insulation will work better. The foil reflection does work, I just need to know if the bubble between the foil will cause problem when nail down the hard wood plank. I just worry that the bubble will cause squissing sound.

 

[lti2000]

Waste of time and money.
How did you insulate under the floor?
Make sure your location is in your profile.
If the crawl space has been air sealed and insulated that's all you need.
There's just no good way to get enough insulation and still be able to have a hard, solid, flat surface to attach the floor to and not have it effect the door openings, and baseboards.

The underfloor is 10" insulation but the crawl space is not air tight. Yes, it can get cold down there and the heat will try to get out thru the floor. Just another protection, (heat reflection, moisture, vapor or any kind) <$500 and leftover from construction, before it hit the hardwood floor.

Also, this is a NEW construction (kind of totally redo), so door opening, baseboard is not a problem.

 

[retired guy 60]

If you do as you plan you will compromise your hardwood installation and accomplish little just as you have been told. If you are serious about wanting to keep the floor warm, then invest in a subfloor warming system using tubing carrying hot water. This system, while not for everyone, has been tested and works.
Insulation goes under the subfloor not between the subfloor and the hardwood surface.

 

[joecaption]

Real hardwood needs a rock hard none moving surface or it's going to flex, squeck, and open up the joints.
All you need is tar paper or kraft paper under it to act as a vaper barrier.

 

[lti2000]

If you do as you plan you will compromise your hardwood installation and accomplish little just as you have been told. If you are serious about wanting to keep the floor warm, then invest in a subfloor warming system using tubing carrying hot water. This system, while not for everyone, has been tested and works.
Insulation goes under the subfloor not between the subfloor and the hardwood surface.

Subfloor warm is a little over for me. I am thinking using this foil sheet as a part/addition to the underlayment (felt sheet). Hence, it can go between the subfloor and hardwood. Some people can treat underlayment as a type of insulation/noise reduction method.

Question still not answer is: if I put the bubble sheet between the subfloor and nailed down hardwood, will it cause the floor float or the nails will hold them well?
I know the bubble foil does well for concrete wall, and attic. But will it do for hardwood floor. Yes, it will do well under the floor joist too but I would prefer to have it installed inside, not outside.

 

[lti2000]

Real hardwood needs a rock hard none moving surface or it's going to flex, squeck, and open up the joints.
All you need is tar paper or kraft paper under it to act as a vaper barrier.

Then it looks like I will consider using the foil paper instead of the bubble.

Thank you joecaption.

 

[joecaption]

Under a hardwood floor all it's going to do is act as a vaper barrer and cost a whole lot more.

 

[lti2000]

Under a hardwood floor all it's going to do is act as a vaper barrer and cost a whole lot more.

I have a leftover roll, just want to make use of it.