thank you, gamountains. You have synthesized what I've been reading - essentially the subfloors and finish flooring have to be equalized to more or less what they will be when we're living there, 12 months of the year. We are in Putnam County, NY, about 50 miles north of the city but with much higher altitude so it could be as much as 10 degrees colder in the winter and maybe 5 degrees cooler in the summer BUT on a lake in a valley and there's a lot more humidity (or so it seems). With the nice breezes we didn't plan to use the A/C very much except to dehumidify when necessary. We have now brought the house down to about 40% RH using dehumidfiers. No one has checked the MC of either the subfloors or the oak that is already on-site but not installed. In addition, there are Viega radiant heat panels on top of the plywood subfloor so they add a third level to check. I have told the contractor not to install the floors until the A/C is in and running and the house is between 55 and 65% RH (which I think is a reasonable average, although we might let it rise higher in the interest of energy conservation and liking fresh air) and the flooring is sitting there for at least 10 days under those conditions. I realize that violates what most have said - 2-3 weeks, but I am operating on the premise that if the R&Q swells after installation, it can be corrected to some extent during final sanding and finishing. Also, my architect says 7-10 days and he's not about to stand up to the contractor he recommended. There will be irregularities in the floor, and I will have to live with that, but given that I don't want my contractor to walk off the job when we're so close to the end, I have to draw the battle lines someplace. The bigger battle right now is over how to get the A/C installed. Please correct me if you see anything that doesn't seem reasonable - can't go for perfection at this point - reasonable compromise is the name of the game now. Thanks.

Did they say anything about engineered flooring over radiant hydronic heat? Would this help without otherwise humidifying? I am considering using engineered hardwood over radiant hydronic heat in a low humidity area (Lake Tahoe). It ISN'T very low humidity. Inside has ranged from 20-50 with no humidification over the last 4 months. It is usually around 20-30 in the summer when the windows would be open anyway, so would a humidifier really work then anyway? However, the house I am looking at is over an open crawl space which I read dries the house out somewhat, so the humidity could be lower there. Thoughts?

They both have a point and are likely basing their suggestions on experience. I believe conventional wisdom says that you should have a whole home humidifier to add humidity to the house during the winter. That would keep the wood at a relatively uniform moisture content. If you don't, there's two scenarios I would predict. 1) If you install and finish the floor while the wood is very dry, it will expand when the humidity goes up. Any filler in the cracks will probably be pushed out, the floor may move due to expansion and/or the edges of the boards may get compressed and the cells could get crushed by the force of the expansion. This could also affect the finish at the edges of the boards since the filler is being pushed up and potentially the cells at the edges of the boards are being crushed. When the humidity goes down the floor will shrink and cracks will appear. 2) If you install and finish the floor while it's less dry, it will shrink when the humidity goes down and cracks will appear. If the cracks bother you, they could be filled when this happens. Once the humidity goes up again, the filler would be forced out and the floor would be tight, like when it was new. When the humidity goes down again, the floor will shrink and cracks will appear again. If I was not going to install a whole house humidifier, I think I'd choose scenario #2. Neither scenario is ideal for the floor people since they get blamed either way, for a situation over which they have very little control.

The AMOUNT of finish (2 coats vs. three) will be more the culprit. And the TYPE of finish (matte, satin, semi-gloss, gloss) will also cause scuffs to be MORE visible (ie. a shiny floor shows 'dull scuff's more than a satin...whereas a matte finish can show shiny scuffs more than semi-gloss). And the COLOUR of the floor will also enhance the look of scuffs. And to be clear, a 'scuff' is defined as material left behind.....not a scratch. Scratching (something piercing the finish causing a break break that can be felt with a finger) is more likely to occur with a poorly finished/poorly cured product. Scuffing is normally a problem with things moving across the floor. Remember gym class? We weren't allowed to wear black soled gym shoes? Why? Because of the black scuffs they made. Black marks. Marks left behind from our shoes. Those scuffs were easily removed (large pink erasures were our janitors' best friends...just like on the butts of a pencil)...but an entire gym class of black soled shoes could cause a week's worth of work for the janitorial crew. And therefore these soles were banned. Move to a home setting. White soled shoes can leave 'clear' looking scuffs. Black soled cause black or dark scuffs. Roller wheels on a desk chair = scuffs. Plastic feet on dining room chairs = scuffs AND scratches. Do you have photos of what you are trying to describe? Scuffs are different from scratches. So I'm wondering if you are trying to say your floor was easily scratched vs. scuffed. And yes...what was the product used the first time and how many coats were used?