Hi,

I have asked questions about installing bamboo in my house a couple days ago, and you people are a great help. But I need more help on making final decisions.

The situation is this: I am planning on installing bamboo floor on on-grade concrete slab. There is radiant heat underneath the slab. Both the slab and the radiant system are 50 years old. A friend (who is a general contractor but not necessarily an expert on hardwood although he's done a lot of hardwood floor before) would be the installer. Based on his recommendation, I have bought 1500 sqf solid bamboo, vertical gain, natural color, measure 3 5/8" x 5/8" x 36. He has experiences with this product and highly recommended it. He would glue it down with Bostik Best.

Getting nervous about the project, I searched on this message board for information about glueing down on concrete. The more I read, the more I know about the moisture vapor emmision associated with concrete, the scarier I am about glue down a solid on concrete (even though it is a bamboo, and technically a laminated product) - If I had known better, I would've bought engineering bamboo instead of solid bamboo. The installer appeared experienced, but he didn't have a moisture meter and didn't plan on testing the moisture level (he claimed that he's done the same thing in houses as mine and had no problems). Finally I got someone else (a licensed contractor) test the slab, and the readings came in unexpected high (14, 9, 7 lbs per 1000 sqf per 24 hour). When I mentioned this to the installer, he said he can put Bostik MVP as a moisture vapor barrier and everything would be fine.

I just don't know if I should trust him at this point. My husband is urging me to do floating with engineering instead of glue down with solid. The problem is I already bought the bamboo (which can 't be floated) and it would a big hassle to return them, not mention the cost of returning (restock fee etc).

So I need you experts opinion on what should I do: do I go ahead with glue down with Bostik MVP/Bostik Best, or should I give up glueing down and switch product to go with floating (or give up on hardwood altogher and go with tile/stone instead)?

I guess I need assurance that glueing down is all right, as long as we install moisture vapor barrier. Is there a limit on how high the moisture level can be to be able to use the Bostik combo and not fail?

Also my neighbors all tell me that it is not a good idea to glue down on radiant heat, because of the temperature variation (we never heat the slab more than 68 degree).
Is this true, even if we take care of the moisture issue?

BTW, glue down appealed to me better than floating because I heard that the pad for floating is not good for transferring the heat from radiant heat. That was the reason why i liked the glue down idea and was talked into it. Can you experts comment on this as well?

Other points I'd like to mention as I don't know if these will/should affect my decision on wood flooring. We don't have air conditioning. We have open floor plan (kitchen/family room/living room/study all open to each other) and air flow is good. We have a big pool in the backyard. We don't have very good insulation in the house, with single pane floor to ceiling window walls all around the house. We cook a lot and during cooking time, the humidity would be high (I can tell because in winter we got condenstation on the glass walls while cooking). I now know that high humidity is not good for hardwood, and I will be sure to buy a dehumidifier to get indoor humidity in check.

Based on all above conditions (indoor condition and slab condition), what would you recommend I should go with my floor?


My carpert is out, the house is in disarray, yet I can't decide how to proceed. HELP!


Joanne

The MVP should bring down those vapor emmision levels. You could call Bostick's with your numbers and ask them. Generally speaking, 3 to 3.5 lbs. per 1000 sq. ft. in 24 hours is the maximun allowable by most flooring manufacturers. Good thing you had that calcium cloride test doine. MVP should be able to bring down those numbers to an acceptable level but I'd recommend contacting Bostick's directly. They should have a tech. help #. Bamboo is somewhat more stable regarding RH levels compared to solid wood but not as good as a quality engineered, IMO. The biggest problem with radiant in a house your age is leaks/failure of the tubing in the slab. What a nightmare if a pipe breaks!

Thanks for your reply, Gary. Also thanks for the tip on where to get Ardex Feather finish in south bay area.

Speaking of leaks in radiant heat pipe, yeah, we are aware of that from the first day of owning this house. I just had the pipes tested and no leaks so far.

That brings up another question though. Should leaks happen in the future, which do you think is easier for repairing the pipes, a glue down floor or a floating floor?

Joanne

With a click together floating floor, it could be disassembled to the problem area, the pipe repaired and the floor put back. However, the flooring would probably be ruined in either case, glued down or floated. The key here would be whether or not you could still get the exact same flooring to make the repairs. And then, the repaired area would likely not match due to the aging of the floor anyway. Oftentimes, a complete replacement is needed because a match cannot be made. A crap shoot no matter how you look at it.