thiamom = carbonized means "baked or burnt"...it's how they get the bamboo to darken without adding a chemical. In essence they put it in the oven until it starts to "burn" and then they take it out. The darkened colour, just like a burnt pie crust, remains forever.
lindshammer - high humidity for bamboo is anything over 75%. That makes bamboo a "happy" camper in higher than normal humidity (most wood is 45%-65% window). Bamboo has a happy window of 45%-75% (depending on the make). Cork has a happy window of 35% - 65%.
Moisture in the subfloor is a major issue with bamboo. There can be no more than 3% difference of moisture levels between bamboo (5-6% moisture content) and the subfloor (plywood must be below 10% moisture content = bone dry). Slab concrete is a major issue with bamboo. Even a small amount of moisture/hydrostatic pressure in a slab will cause the bamboo to fail/have problems. Moisture mitigation can quadruple the amount of money to install (properly install) bamboo over concrete. The same reasons why hardwood is not suggested to go directly over slabs in humid areas, is the same reason why bamboo should not go down over the same slab. Almost all wood products have these issues.
Manufactured products (like bamboo, eucalyptus, engineered hardwood, laminate flooring, even some cork products) have more chemicals added - the more "natural" products such as hardwood, wool carpets, ceramic/porcelain/cement tiles have less.
A cork floating floor only requires a vapour barrier to be installed over a cement slab and then the floor is clicked together over that. Forna cork floors have been produced using 100% VOC free/Formaldehyde free adhesives/binders = very low emission floors. Why so low...because we use German manufacturing techniques, with German/EU standard binders and finishes = EU standard air quality control/emissions.
I have a contact in Canada who sells EU standard bamboo flooring = no formaldehyde binders. He will know who to contact in your area. Visit: www.superiorbuiltproducts.com he will help you find out where/who carries his manufacturer's bamboo in your state.
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