Underlayment Options for Bamboo Over Wood

[CaptainJAllen]

I will be installing a strand Bamboo floor over a wood substrate. It will be a nail-down installation with tongue and groove boards.

This is on the first floor over a crawl-space, so sound deadening is not an issue, but moisture from under the house may be.

The floor is flat, but not perfect as it had carpet installed previously and there was a wall that has been removed.

What should I do for underlayment? Don't want to spend money unnecessarily, but want it to be right. Do I need more than felt-paper since the floor is not perfectly flat?

 

[DennisT]

How far off is the floor from the Bamboo mfgr's recommendations?

 

[CaptainJAllen]

I have a piece of flooring to replace, but I think I will be within it. The specs are 3/8 over 6 feet, I believe.

 

[Ernesto]

You can use Aquabar B under the wood as a vapor retarder. You can build up low spots with some paper then sand or plane down high spots.

Here's the new way to protect your hardwood from crawl space moisture intrusion.

http://buildingscience.com/documents/insights/bsi-009-new-light-in-crawlspaces

 

[Nick]

Good Post E.

 

[CaptainJAllen]

Thank you all. I am replacing some of the subfloor to get it within manufacturers recommendations and going simply with a vapor barrier.

 

[DennisT]

Have you determined which nailer you're going to use? Strand is really hard and dense. Too big of a gauge and you'll split the tongues off. I installed a few 100 sqft of strandwoven timber. The same as bamboo but made from wood fiber scraps. I ended up renting a Primatech 550 (18GA cleats) and it worked really well.