Greetings,

I am a pencil-pusher by trade. Wife and I have recently purchased a well-preserved elvis-palace that was built in 1973, and not touched since. We are tearing up the wall-to-wall dog-urine-colored carpet, and I intend to install hardwood, with ceramic tile near doors, in kitchen, and in entry. If I may, I'd like to describe our subfloor, crawlspace, and planned DIY installation, and I would very much appreciate comments or advice.

Location: NW Washington State, a rotten-apple throw from a saltwater marina, and a long golf shot from Puget Sound. Climate and humidity regulated by proximity to the Sound (I think) - heat of summer rarely exceeds 80F, and snow is a rare thing. We do get an occasional dry cold snap, when the northeast wind blows in Jan/Feb.

Crawlspace: 90% covered with poly when built - south end of house (facing marina and bay) seems to be the lowest, and is location of no poly cover. I did see standing water this winter at that end of the crawlspace. I don't think the builder left enough fill inside the foundation wall, and the water is sneaking in under the foundation tile - it was pretty easy to excavate and find the bottom of the fdn wall at that end of the house. There are 8 vents for about 1300 sf (~25'x50'), and they are clear and functional.

Subfloor: 2x6 (1.5x5.5?) fir t&g decking, laid perpendicular to 4x8s on 4' centers. The 4x8s run the length of the house. The portion I've exposed after tearing up carpet and particle board is in good shape. From underneath (after crawlspace survey - lots of spiders!), the fir decking and the 4x8s look bright and like new.

Mechanical: I will be installing forced-air gas heat this summer. I have installed a wood-burning fireplace insert at the far south end chimney, and will use it extensively. I may install another at the far opposite corner of the house. I like wood heat. I have no intention of installing air conditioning for the ~10 days a year where it might feel usable. It's generally pretty breezy here when the sun's out in the summer.

I want to install solid, prefinished braz cherry. I have located some which may be obtained at a good price - 3/4" x 4" wide. I obtained a sample box - it is straight and well finished. It does not have finish on bottom, sides or ends.

My good friend is a house builder, and has some experience installing hardwood. He does not have experience installing on a t&g fir-decking subfloor. He figures that, if the decking proves to be uniform and level, I can install the hardwood right over the decking. I am concerned about squeaks and pops, since the flooring will be parallel to the 4x8s. He acknowledged this, but figured that the beef of the fir will handle it. I'm tempted to nail straight to the fir as well, but lay the wood out at a 45 degree angle to the walls. My last option is to screw down some plywood and install over that, losing 1/2" on an already lowish (7'10") ceiling.

Anyway, here's the plan.

1. excavate a sump in the crawlspace - install automatic sump pump - route outlet to birdbath in backyard and frighten birds when it randomly turns on (maybe). Cover remainder of crawlspace with poly sheet.

2. install hardwood.

My specific question is:

Which of the 3 installation options should I choose?

a. flooring nailed perpendicular to t&g fir subfloor, and therefore parallel to supporting 4x8s.

b. flooring installed at 45 degree angle to fir subfloor (does this look strange? it would actually line up well with the existing hearth on the south, and the planned hearth on the north)

c. glue and screw 3/8" or 1/2" plywood, and install flooring perpendicular to 4x8 beams.

also, should I apply some sort of finish to the unfinished bottom and sides of the flooring?

Thanks,
Jerry

Heh Jerry, I spent a lot of time do floors up there. Any one of your three options will work. The only thing you can't do is lay parallel with the car decking without ply. Figure more waste and labor with the 45 deg. You just need to make sure the surface is smooth. Plywood is best if possible and you can lay/change any direction you want.
Looks like you could use some more crawl space vents, code down here is 1-1/2% per floor space.They should be evenly spaced around the house. Check the downspout exits and direct them away from the house.
I suppose the only thing I would advise against is your choice of wood. It is about the most unstable wood commonly sold as flooring today, in fact I believe far oversold. I don't understand the way its being bought up, a trend I suppose. You should allow extra time for acclimation, we used to spec 4 weeks (minimum!). The wood heat is going to dry it out good in the winter and you'll see plenty of expansion in the summer. This is compounded by the wider width. i see BC floors I installed 12 years ago in a climate controlled environment (Macy's) that i believe look awful, massive cracks. Guess its ok if you want the rustic look. Have you considered Santos Mahogany?
I have never finished the underside and don't know if it really helps or is a gimmick. Don't do the sides. Maybe somebody else here knows, up in Seattle the flooring companies compete to give away free advice and one of the best advisors in the country happens to own the Oak Floors of Greenbank. Give them a call, they know your locality.