I have been installing hardwood for 7 years now, and run the installs for 13 major retail stores. Since I started I have used pl400 and glued the first row, and the last 3 rows. (I have never had an issue) I went to my supplier to pick some up and they told me that they will no longer sell it due to the fact that it does not provide enough allowance for movement. OK??? then he proceeds to tell me that they are switching to pl premium because it provides more movement. Is this guy crazy??? my experience with pl premium has scared me into never using it again, if you let any dry on the floor, good luck getting it off!! even on the back of the tube it says the only way to remove it after it has dried is to use abrasion, which works great on a prefinished floor, NOT!!!! not to mention that it dries much harder than pl400 right???

Anyways, is it true that the NWFA will not even look at a floor if pl is used?

and second is there a good convenient glue that comes in a tube' that will do what it needs to do, and not cost a fortune.

I know that some guys say that you can topnail the last 3 rows, but that is awful looking

any opinions on PL400??

I dont have any issues with 400 or Premium. Their selling Premium because it's cheaper. Just wipe it off the wood with paint thinner before it cures. Or go to Big Box for 400. Their both Urethanes.

Any urethane adhesive will do the job, some keeping more flexibility than others, but all workable.
I don't understand what NWFA would want to be "looking" at the floor for anyway.
The key here is, you are trying to make your installs look as good as possible by eliminating or reducing the number of face nails. Keep up the good work and dont listen too much to the salesguy at the hardware store.
BTW, although I agree with you about not wanting to nail through the surface, we (our company) always suppliments the adhesive at finishing walls with small (23 gauge) brads to expedite the installation.
These are virtually invisible on their own, and properly filled, I would defy anyone to locate them without a "hands and knee" inspection.

I have found that when I supplement the adhesive with finish nails ,the 23 gauge nailer is a small enough nail gun to toenail into the tongues. The last row is top nailed with 16 or18 gauge, ( for additional strength ), hidden by the base boards. This avoids any exposed top nailing.

Ya we do pretty much the same, Floorologist, but rely on the glue for holding power so we dont bother switching back to the 16 gauge spikes (lol)

Ya , the only difference is we tend to stay away from top nailing completely, even with a 23 gauge . It's noticable in the light, also every filled spot ,on light floors , grabs dirt and turns dark . We switch to a 16 gauge on the last row to avoid using wedges while the adhesive is setting. I have found that a 23 gauge wire will not hold the floor tight while the adhesive is setting.

The salesman said that they were having issues with their floors cracking, (hairline cracks perpendicular to the butt joints) and they think that its because the floor was being held too tight by the adhesive and not being able to move. In a few cases they had to get a mediator involved (NWFA) because no one would take responsibility. They proceeded to tell me that the NWFA will not even look at a floor if PL400 is used, in other words, they will not approve the use of PL400....

In my experience, 23 gauge nails are not strong enough to hold back the last rows, but Floorologist, why do you avoid using wedges?

Absolutely, that's why I use 16 gauge on that last row

I actually use wedges all the time on gluedown over concrete. The only reason I dont use wedges on naildown is a time issue. Usually at that point of the install ( the last few rows ) , I'm ready to install base and cant pull wedges until adhesive is set. Gluedown over concrete I'm stuck waiting. ( That's when I work those extra hours at the end of the day to get to that point, and pull wedges the next morning, so I'm not waiting for adhesive to set).

I use PL Premium exclusively. The 400 and liquid nail equivalent, dry way too brittle. Liquid nails actually says not to use with wood flooring.

PL Premium, is just like Bostik's Best, or Mapei 990.

Especially if your building up a sunken livingroom level with the upper deck. KABOOM!!!

Sounds like you have experience with that one.

Not personally, but a few years back a guy was sheeting over a sunken livingroom, got most of the way across and whatever fastener he was using made a spark that lite up the fumes from the liquid nails that had collected under the subfloor and blew him up into the ceiling. He died.

Why can't they come out with BB in a tube. I love how it stays flexible (elastomer?)

I think they do have it in a tube Fast. I use the Pl premium most of the time because it allows for movement.