Hi, I am in at the tail end of a complete reno and I have hardwood coming to et installed on Monday.

How clean should/must the subfloor be? I have swept the whole house as best as I could, but of course there is still some dust (saw dust and sanding from drywall), that its very fine and I cannot get rid of it all.

Should I clean it so there is absolutely zero dust?

 

There could be more dust coming, so ask the contractor some questions.
If they need to level the floor and sand it, there will be some nasty dust and a lot of it.
Ask them if they think the floor will need leveling and sanded and how they plan to deal with the dust.
From my experience, sanding leveling compound without any dust containment is unacceptable to most customers.
The floor doesn't require a dust free surface, but the installer needs to avoid making your house a mess like you won't believe.

 

Hopefully the hardwood is already acclimating in the house. They can not just show up on Monday and install, it needs to come to equilibrium with the environment that it will be installed in for at least 72 hrs. Sweep all you want, but vacuum with a shop vac before the install happens.

 

Really? Even for engineered? This is what it says on the install instructions, if not followed, the warranty could be void: It is Superior hardwood.

Enhanced Flooring Inc. will only warranty product installed by an approved Enhanced Dealer.
Longevity of hardwood floors is directly related to proper installation.
DO NOT ACCLIMATE Enhanced Hardwood Flooring PRIOR TO INSTALLATION. Flooring must be installed
immediately upon opening the boxes. Enhanced Flooring Inc. product should be one of the last items
installed when renovating your home, cottage, chalet or condominium. For new construction the
heating system must be operating for at least one week (7 days) at normal residential temperatures
approx. 70ºF/22ºC prior to installation. The relative humidity level in your home must be targeted at
50% (i.e. between 30-65%) throughout the year. Where conditions in the home have high and low
humidity levels, Enhanced Hardwood Flooring is much more dimensionally stable in comparison to ¾”
solid hardwood flooring.

 

There is not a single hardwood floor - solid or engineered or laminate that I would install without acclimating first. But in your case, it is not my warranty or reputation that is at stake.

 

Get a humidistat to check the humidity level. If there's been drywall work, etc the humidity level may be high.....hear a lot of stories about new builds and renos having too much humidity for new flooring. Interesting installation instructions. Based on the fact that you've had reno work done I would contact the manufacturer's techies and get an opinion on the wisdom of doing an immediate installation. Just my 2 cents.
Also, get the floor flat....remove drywall mud lumps. Run a shop vac and install a vapor retarder as required (Aquabar B is a good vapor retarder).