has anyone ever floated engineered hardwood across multiple adjoining rooms? need a game plan for my DIY installation in 3 weeks. floor needs to flow from one room to the next (no transitions). many of the videos cover doing one room and the recommendation is to start in the corner and work left to right, but I've never seen anything when there is multiple adjoining rooms. I've read about snapping a chalk line parallel to the longest exterior wall thru multiple rooms and essentially starting in the middle and working outwards. Has anyone ever done this using the floating method? are there any other strategies for tackling multiple rooms?

It can be tedious if you have to wrap around walls and undercutting door casings deep is needed to eliminate transition strips. I just wrote a little article on using a floating glued T&G engineered. You need lots of tools and experience to properly execute this.

http://www.floorbiz.com/BizForum/MSGVie ... sp?ID=1423

Thanks Steve. I was recently told by someone at lumber liquidators that t-molding between rooms is recommended when floating engineered wood across muliple rooms, so the floors can independently expand and contract in each room. Do you agree with this? We don't want t-molding anywhere. Due to this, we are also tinkering with going with solid hard wood and nailing into the subfloor? Would this make the task of doing multiple adjoining rooms any easier?

Some say leaving extra expansion space under door casings/jambs, around perimeter at walls, will suffice eliminating t-mouldings in doorways under 4'. I don't think there's a manufacturer out there that buys into that. It's a grey area. If the material is acclimated properly, and the environmental conditions in the home are kept very stable...you MAY get away with it. Although even under keeping strict environmental conditions....each room in a home will expand/contract at different rates, causing excessive pressure in that narrow doorway. One good thing....If you opt to try and elimate t-mouldings in doorways..., if it creates a problem...., most of the time you can relief cut, and the floor will rest back down, then add the t-moulding at that time. T-mouldings can be an eye sore. I've played that game a couple times, depending on layout, and knock on wood, it's worked. But I always explain the situation to the customer...

It depends which way the floor is running and if the sheetrock is also undercut to allow more expansion, if needed.

I just did a glue together floater.... Took me longer than a gluedown!!!
First one in 6 or 7 years, since the glueless T&G made an appearance

Since when does it matter which direction the floor is running, in relation to installing a t-moulding where required?

For that matter.....What does the direction of the planks have to do, in regards to a required t-moulding, due to differences in environmental conditions from room to room, in doorways under 4' ?

Another problem can be created with transitions and floating floors; locking in the areas. Let's say you've left the channel or gap where the molding is to be inserted. Most inexperienced people won't think twice about loading the channel up with glue then dropping the molding into place. Once the adhesive cures it's almost like a wall. It can't expand properly if needed.

There is more strength in the assembly, if the planks fall through the doorway and not along it.

The stagger running through, will be stronger than a single joint across the doorway.

Uhh...It depends on which direction the rooms are moving....

Sorry, I haven't seen it stated by any manufacturer that depending on the direction the planks are running on a floating floor, through a doorway, you can avoid a t-moulding

When your dealing with 2 seperate rooms that are moving at different rates, and a 3' doorway seperating those 2 rooms....It doesn't matter what direction the planks are running. With the strength of those rooms moving, seperate from eachother, there's a better than average chance your going to encounter quite a force,( in either direction) at that little 3' doorway. It's a game of Russian Roulette....

Stagger adds strength.

A few dabs of Titebond III, adds even more strength.

Let me get this straight......6 staggered floating planks, ( oh I almost forgot the dab of glue), in a 36" doorway, is not going to blow off the floor, when the 400 sq' room moves at a different rate than the adjoining 300 sq' room...

Roll the dice...

mschell, all engineered can be fastened to a wooden subfloor/underlayment unless it is a click system. Not sure why anyone would want to float it when you could simply fasten it. That eliminates all the confusion about transition strips since you would not need them. It surprises me that LL would not tell you that unless it is a click system.

In an interior it is all going to move at the same rates, unless you have a window AC unit in one of the rooms and keep it closed off from the other.

Now, what I think you really mean, is trying to move in different directions.
A single joint running parallel to the doorway is going to be very weak and I would not even attempt it. If the direction of the flooring planks run through the doorway, it will have more strength and be less likely to separate.

Then... Is the doorway on the end of the room, side of the room, or in the corner of the room?

A glue together is going to be a much stronger assembly than a click lock glueless assembly.

A running length of flooring and expansion space, since you went to an extreme sq.ft. (300 & 400 sq.ft.) measurement, is another topic all together. There is more mass in that floor than a 12x12 144sq.ft. room, to prevent much rotational movement.

If you understand the strengths and weakness of building a panel out of T&G boards, that are very stable, then you too can pull off and meet your clients expectations and be able to warranty your work for as long as you are breathing, while sleeping good at night.

There are some floors that are glue down only.

Bruce/Hartco/Robbins/Armstrong have some that are gluedown only.

Some points you say I do agree with, and I am very aware of, BUT...These points are under varying circumstances, and don't exist in all floating installations..

The installation procedures mentioned are inventive, and to hedge against manufacturer requirements. And for that matter, to justify and buck warranties on a floating installation. Everything actually is related and stems from one statement... the very basis of this thread.

"In an interior it is all going to move at the same rates, unless you have a window AC unit in one of the rooms and keep it closed off from the other."

Different rooms in a home expand and contract at different rates. This is intensified on floating installations. Environmentally....as you walk through a home, you will encounter rooms with different exposure to HVAC and RH conditions. Seperate from or causing these conditions are, location of rooms, windows, duct work efficiency/uniformaty, etc. etc. Not only do I regularly experience this in customer's homes..but in my own.

Not to mention...different amounts of footage in different areas, expand and contract at different rates.

These different conditions, in different areas, causing different amounts of movement, seperated by a 3' doorway, combined with the movement of a floating installation, is a touchy situation.

Granted.....I am a huge advocate of thinking out of the box, and have avoided t-mouldings where possible myself. IMO, they're an eyesore. It's important to meet and hopefully exceed customer's expectations. However, us as the professionals are required to know what's realistic. I will weigh out the conditions very carefully, and complete scenario, before I feel comfortable. There are reasons why manufacturers specify t-moulding requirements for floating installations.