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Rusty-
Do not glue the floor, it needs to move with humidity/temperature changes.
When the flooring arrives, crib stack it inside the house convenient to the installation area. Let it set there for 10 to 14 days to acclimate to the humidity of the house. If you have a humidity meter for wood you can gauge progress and possibly install sooner. The crib stacking is to allow room air to circulate around the stock. Humidity acclimation is to prevent later shrinkage or expansion after installation, not a pretty sight.
Expansion can cause the wood to walk and buckle, even slightly, and the floor will always look uneven. Shrinkage will cause gaps to appear along the side seams or at the butt ends. Usually happens at the butts.
Allow about 1/2″ expansion space all around the room. You can also allow 3/4″ expansion space around, especially if you can’t allow the time for the material to “cook” before installation. I work with the 3/4″ space and form it by standing flooring pieces on edge against the starting wall. Knock them out after the first few courses are in, because a little swelling will make them difficult to get out later. You can baseboard afterwards and dress out any remaining space with a 3/4″ quarter round. Oak is best for durability from furniture scuffs.
Vacuum the floor clean before starting. Then start the floor with rosin paper in overlapping courses, each new course tucked under the preceding course,
so that you can sweep any dirt or debris away from the installed flooring without brooming it under the next piece of rosin paper. No staples in the paper, they cause squeaks. That’s also the main reason for using rosin paper, to prevent squeaks from wood to wood surface movement.
You can rent pneumatic staplers or nailers. I prefer the staples, but use 2″ fasteners either way. Nail at 8 to 12″ o.c., 8 or 9″ is best. Closer nailing than 8″ breaks the tongue off the board. Don’t worry about nailing into floor joists, the fasteners go in on an angle and will only penetrate a joist by about 1/4″ with a 3/4″ floor deck/
Keep joints 8″ from the joints of the preceding course. This makes the floor strong, prevents squeaks and creates a visually appealing floor. Seams that are too close attract eye attention. Do it the right way, and the floor flows visually.
Avoid “staircasing” where joints progress from course to course to look like a set of stairs. Also, avoid a “ladder” or “H” effect where joints in adjoining courses set up a pattern like the rungs of a ladder, or the letter “H” repetitively.
Take some time and the floor will be a showpiece. If not, it will just be a new construction “blast and dash” job. Best of Luck
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My house will have a crawlspace with 3/4 TG decking. I will be using full 3/4 TG hardwood flooring in much of it. I've always seen this just nailed down over a layer of rosin paper. But I had a friend tell me recently, "Oh no, you need to glue it as well as nail it, or you'll have squeaks." I've never heard of gluing hardwood flooring. But he said that's what the "relief" of the back of the strip is for -- the glue. I think it's to make the board lie flat.
If I use a good quality decking, glued and screwed to the joists, and nail the flooring catching every available joist, will it still squeak? Or is gluing becoming an accepted practice?
*Rusty, never heard of gluing and nailing and the relief on the backside being for that glue. Course, haven't heard it all anyway. If you do it your way, it probably won't squeek but there's always a chance. I would think subfloor, nails, moisture content of hardwood, and vapor retarder in crawl, would be of more concern. I'm sure some of the resident flooring guys will have a much more qualified opinion. Best of luck
*No offense to him, but your friend sounds full of ... misinformation. You're right, the relief helps the board lie flat over subfloor irregularities, and perhaps to curl down instead of up when it swells -- anyway, you don't need to MAKE space for glue!The rosin paper is there to allow the strips to move without squeaking against the subfloor. I think the squeaks usually come from the subfloor moving against the joist (which reminds me, I'm going to try to fix some in our house today!). The surface finish floor must move with fluctuations in humidity, and unlike the subfloor all the grain runs in one direction -- making for a lot of movement.Interesting, in our house the first floor is hardwood + builder's felt + diagnoal plank subfloor; the second is hardwood alone over the joists. The first floor has squeaks, the second none. This is a 1940's cape, long before the Age of Plastic.You might be interested in a "floating" floor, the pieces fastened to each other but not nailed down at all.But I'm no floor expert...
*Rusty, Personally I would forget the glue and pay attention to other details. The crawl space needs to be properly vented to begin with. Moisture building up in your crawl space will wreck havic on more than just your floor. If need be and possible insulate your floor as well. Gluing the floor tight to the subfloor and having the potential difference in movement due to moisture, heat and cold could cause cracking in your hardwood flooring. I know many construction adhesives are flexible, but I have had it happen. Nailing down strip flooring over a paper barrier has a bit of history behind it. Just as Andrew mentioned, the rosin paper acts a as buffer between the two floors for expansion and contractions just as the edge nailing allows the same. Also the paper acts as a air barrier between your crawl space and main floor. Not as critical today with sheet sheathing but when boards were used as sheathing, it would make a difference. Going back to details though, I would recommend either 1x t&g boards or a good quality 3/4 sanded one side plywood for your subfloor. Nail it down using 8d screw shank nails per adequate nailing pattern. Reject what anyone else tells you about using OSB plywood or any of the other "super" subfloor materials. They do not work. They do not hold nails. They will swell with moisture constantly. If you use boards or plywood, you do not need to worry about hitting the joists with your flooring. I use 2" flooring nails for most applications and have had no problems as long as my subfloor was acceptable. I donot like flooring staples though I know some who find them okay and use them regularly. I also like the armstrong flooring nailer rather than the pneumatic ones. Another detail that is important is to make sure your subfloor and flooring are dry, about 7% maximum if at all possible. You can heat the crawl space to dry the subfloor as that is usually the hardest area to dry. Most flooring comes delivered in the 6-8% range. When installing your floor fit the pieces tight as possible but remember to leave an expansion area against your wall plates, 1/4-1/2" is adequate. If moisture in the crawl space is still a concern, use 15# builders felt as your floor paper. It will help with the moisture transfer. Just overlap the edges 6-8inchs. I have installed a bit of flooring over the years from strip flooring to wide plank flooring. I also have worked on renovating a few old houses and have gleaned what I could from their construction experiences. I may be a bit of a dinosaur when it comes to construction ideas, but I find they work well, and question the durabilty of the glues used so frequently in building today. Anyways Rusty good luck. Walk good David
*Rusty-Do not glue the floor, it needs to move with humidity/temperature changes.When the flooring arrives, crib stack it inside the house convenient to the installation area. Let it set there for 10 to 14 days to acclimate to the humidity of the house. If you have a humidity meter for wood you can gauge progress and possibly install sooner. The crib stacking is to allow room air to circulate around the stock. Humidity acclimation is to prevent later shrinkage or expansion after installation, not a pretty sight.Expansion can cause the wood to walk and buckle, even slightly, and the floor will always look uneven. Shrinkage will cause gaps to appear along the side seams or at the butt ends. Usually happens at the butts.Allow about 1/2" expansion space all around the room. You can also allow 3/4" expansion space around, especially if you can't allow the time for the material to "cook" before installation. I work with the 3/4" space and form it by standing flooring pieces on edge against the starting wall. Knock them out after the first few courses are in, because a little swelling will make them difficult to get out later. You can baseboard afterwards and dress out any remaining space with a 3/4" quarter round. Oak is best for durability from furniture scuffs.Vacuum the floor clean before starting. Then start the floor with rosin paper in overlapping courses, each new course tucked under the preceding course,so that you can sweep any dirt or debris away from the installed flooring without brooming it under the next piece of rosin paper. No staples in the paper, they cause squeaks. That's also the main reason for using rosin paper, to prevent squeaks from wood to wood surface movement.You can rent pneumatic staplers or nailers. I prefer the staples, but use 2" fasteners either way. Nail at 8 to 12" o.c., 8 or 9" is best. Closer nailing than 8" breaks the tongue off the board. Don't worry about nailing into floor joists, the fasteners go in on an angle and will only penetrate a joist by about 1/4" with a 3/4" floor deck/Keep joints 8" from the joints of the preceding course. This makes the floor strong, prevents squeaks and creates a visually appealing floor. Seams that are too close attract eye attention. Do it the right way, and the floor flows visually.Avoid "staircasing" where joints progress from course to course to look like a set of stairs. Also, avoid a "ladder" or "H" effect where joints in adjoining courses set up a pattern like the rungs of a ladder, or the letter "H" repetitively.Take some time and the floor will be a showpiece. If not, it will just be a new construction "blast and dash" job. Best of Luck
*The big downside to gluing that comes immediately to mind is that you'll be SOL on ever doing any kind of repair to the glued hardwood. I'm remodeling a large 1926 house, and in the process I've taken up the oak in three closets to get matching material to fix damage in the main rooms. (Two of the closets are back to back, and I'm combining them into a mini-office.) It looks like the original construction used tar paper under the hardwood in the main rooms, but not the closets. Go figure.I've heard of, but not tried, getting talcum powder to work into the joints between the hardwood to lubricate it so it can move without squeeking.-- J.S.