Hi, I'm new to the forum, so I apologize if this has been asked already. I live in Michigan and added a new room to the house this past fall. Construction has been complete for about 6 weeks now. I want to install a 0.25 x 2.25 inch solid oak floor, prefinished, made by Bruce. It's 20 degrees outside, cold and snowy, and a little dry inside. How can I avoid problems as summer approaches and humidity increases?

Here's the facts:

- Temperature in new room varies between 65-70 deg and has been heated
- Humidity now is about 41%
- Subfloor is a 3/4 inch structure wood (with tongue & groove, I believe) and appears to be well-acclimated
- Subfloor is screwed to rafters with insulation between them, and the insulation is covered from below with brown paper
- Under the new room (about 12 feet below) is a concrete slab poured in August with doors that open to the outside
- The new room opens up to the old kitchen, which has a similar flooring arrangement (2.25 inch solid oak floor). This floor develops gaps in the Winter (about 1mm every 20-30 inches or so)
- I plan to leave 3/4 inch expansion room on all sides of the floor
- The new room is about 12 feet wide (the width of the planks will cover this span) and about 20 feet long (the direction the length of the boards will go), and the floor will be installed perpendicular to the joists. It has windows on three sides (it's called the sunroom).
- Summer humidity in the house goes up to 55% or so, maybe higher (can't remember the exact figures) and is air conditioned.
- The new floor has been acclimating in the new room for 4 days so far, and I plan to let it acclimate for at least 7 days (longer if needed).

I don't know the moisture content of the planks or sub-floor yet (I have a moisture meter on the way from Amazon.com), but will have it thoroughly checked prior to installation.

Can I install the floor now?

How can I avoid buckling/cupping as the humidity increases?

Do I need to make expansion gaps in the planks every few boards (I read that this can be done using small washers)

Should I put in extra nails?

Thanks in advance!

Clear that part up a little. By brown paper are you referring to the kraft paper that is attached to the fiberglass insulation? If so, the paper side should fit firmly up against the bottom of the subfloor with no air space. If its installed upside down the kraft faced vapor barrier will trap moisture between the subfloor and the paper causing the insulation to stay damp if moisture ever gets in there.

Wait for the meter but I see no problems to hold up the install. It's all about trying to maintain a year round comfort level for the wood.

Yes, it is the kraft paper attached to the fiberglass insulation. The paper is firmly attached with no gaps. I also forgot to mention that I will use Rosin paper underneath the new hardwood floor.

The moisture meter came in yesterday, it's the Extech MO200, and I now see form previous posts this isn't the best one to use since it can't be calibrated for various wood types. The only value I see in this is to compare the moisture content of the existing floor (right next to the new floor) with the moisture content of the new floor. It currently shows 6% for existing oak floor and no reading for new floor yet.

I have the MO200, waste of money IMO. Hard to get an accurate steady reading. I wish I hadn't bought it and bought something else.

Any of the pros have any advice for me before I begin? Is there anything I need to do during installation to compensate for dry conditions or will I be ok?

The room is 12 ft in width? Put it on in, or you could start in the room center and work both ways. You would need some splines if starting in the middle.

Why would you start in the middle of the room?

They say wood expands toward the tongue side, this would help cut down on expansion issues if someone is concerned about that.

Actually I think Jerry meant, the tongue side where the fastener is, and the angle of the fastener is the path of least resistance. So the floor moves that direction first.

I'm not sure what I was trying to say.

Would I put a humidifier both upstairs and downstairs? Or if I put it in one or the other, will it magically work the whole house? I do have central heat/air if that matters.