4

There is no reason to glue down engineered hardwood floor to an underlayment. This is just for initial aesthetics. The glue will NEVER last (in a residential setting). The only thing the glue will do is give you fits and make your install seem tighter. Within weeks or months the glue will come loose and you will have a floating floor. Nothing wrong with ...


4

We installed an 18' diameter pool on top of a concrete pad using the 2' x 2' interlocking square foam pieces between the pool and the concrete. It feels great underfoot and the pool has been going strong for 4 years now.


4

The first issue you need to address is why is the base eroding in the same place time after time? The large majority of above ground pools survive many years with a leveled sand base. The probable reasons for your erosion problem is an unstable base, misguided water runoff or the base is a bit too high in relationship to the surrounding area allowing runoff ...


4

Per request, I'll expand my comment into an answer: as for the joints in the concrete, I'd use polymeric sand (typically used for locking pavers). Then the key is to create some sort of smooth pad in between the concrete and the bottom of the pool. Some options: roofing felt (tar paper). Ice and Shield roofing membrane rubber pond liner epoxy (if it's ...


4

There are several good foam type underlayments available. For maximum sound proofing, I'd probably recommend one of the high density closed cell foam pads as opposed to the standard blue or white 1/8" lightweight styles. You may have to visit a flooring specialty store, I have never seen the better grades in stock at the box stores, although they may be ...


4

The reason the floor materials aren't as effective is because this problem is best solved with an air-gap and a flexible connection spanning that air-gap. But you have a hard time supporting a floor with that air-gap. Therefore, solving this problem via the ceiling below this floor is better, using resilient or sound attenuation channel there. That said, on ...


3

Answering my own question here with an email response from a Green Glue associate. In response to me basically asking him the exact same thing as in my original question: This application will certainly work. We would recommend using the heaviest & thickest material that you can...1/4 plywood is going to be a bit too light & thin. If height is ...


3

Your current plywood is suitable for hardwood installation. I do not ever like to use 1/4 subfloor as it is brittle and when screwed sometimes doesn't lay flat. If I added to your subfloor I would at least put in 1/2 inch but like I said you don't need it with 16" OC. Note that a thicker sub might have benefits but at the same time you are adding weight ...


3

I would not bother with used pad . You can get new inexpensive rubber pad of the appropriate thickness when you need it. I have reused older type pads , you can never get them clean; dirt goes through the carpet into the pad. And , I have used new pad trimmings for attic supplemental insulation , again ,the used pads are dirty.


2

You don't have to glue it but it needs to be secured somehow - duct tape. Don't want the pieces rolling up on each other over time. You would just be duct taping the underlayment to the outside flooring or in the inside seams. And duct tape isn't hillbillying your floor. It is used because how well it handles moisture. Maybe someone has a specific ...


2

If the subfloor is plywood no other ply is necessary; but you do need a flat surface for the Ditra. If the subfloor cannot either be scraped, chiseled, or sanded flat then self leveling compound may be required. If you use self leveling compound remember that the surface should be primed first - follow the product's prep recommendations. 1/8" plywood, in ...


2

A flexible underlay will compact when walked on. This helps if your floor is slightly imperfect (it is) and people walk on the tongue-and-groove connections (they will). The extra stress could cause the connector to snap off one of the boards. A more compelling reason is that any slight dips in the floor will cause an audible sound every time you step on it ...


2

In agreement with the above and further suggest: 1) Walk the existing floor in silence, use 1-1/4" screws to eliminate real or perceived squeaks. 2) Pay attention to the butt joints, if they are swelled knock them down with a belt sander. 3) At the top of the stairs be sure the entire area is screwed down well, it takes brutal traffic. 4) Go opposite the ...


2

DO not overlap as it will cause a noticeable uneven floor when walking over the areas. We cut to size and tape where the underlayment meets. Overlap the wall areas and once flooring is complete prior to baseboard installation, simply cut along the edge (leaving a 1/4"-1/2" overcut) and tuck the underlayment under the sheetrock. This allows an overlap of ...


2

You need to tile over a solid surface. Needless to say, this stuff doesn't count, so you'll need to remove it. With a wooden subfloor, the preferred tile base is cementboard. Screw it down, mortar the seams, and go to town with your tiles.


2

This is a subjective question that depends on individual risk tolerance. I wouldn't bother. My previous home was a similar situation, with several cracks and no expansion joints. It was obvious that the basement was perpetually dry and the cracks stable. (They probably occurred as a result of initial settling 50 years ago.) I applied fiberglass mesh to the ...


2

First, I'd counter your plans to orient the second layer perpendicular to the subfloor. Plywood and OSB have a strength axis that should run across the joists. Instead of turning the top layer, simply stagger its joints with respect to those of the subfloor. Start with a ripped half sheet and stagger the butt joint by two joists. I've never heard the ...


2

Plywood would be a very good choice. You should consult the ditra literature for your particular joist spacing, however, generally the bare minimum thickness for plywood/T&G subfloor under ditra is 5/8". Plywood in general adds more strength to a subfloor than cement board, and given that you are going over it with ditra, it makes more sense to add ...


2

The question is quite broad, but there are two primary differences (aside from cost): sound management and the ability to level imperfect subfloors. Sound management (deadening, which can reduce tapping noise) depends on the thickness and composition of the underlayment. Leveling ability is primarily a matter of underlayment thickness. You'll need to ...


2

I would use 1/4inch Luan panels and install without adhesive. Just install to manufacturers specs. This is typically to lay it down and use 1/4 inch crown staples, 1 inch long, every 6 inches along the perimeter and 8 inches in the field. A few things to note: Make sure the subfloor is secured before using the Luan. Make sure there are no protrusions from ...


2

I just did my concrete floor for vinyl plank, and I would be concerned more for the flatness the the floor that it is within the tolerances needed. The bumps can be scraped off, at worst ground off. When I poured mine, I had high spots that needed ground down, quite the dusty job. The holes in the mix from the air bubbles will be of no concern, the flooring ...


2

Unless installing a rigid material such as new plywood, luan, cement board, etc - you generally do not nail it down. When you do, ring shank is the right type of nail. But it has to be a decent quality nail vs. the cheapest bidder, also, the condition of the flooring it is being nailed into is quite important. Just nailing into plywood isn't going to cut it ...


1

In this case it is highly unlikely that the actual brand of glue matters. Use your generic brand glue. Honestly I'm surprised it's a glue down floor at all. Usually the laminate floors are floating - at least in my experience...


1

The goal is a smooth, flat surface for the vinyl to lay on. If you can do that with 1/4, then that is great. But in your case it sounds like you need to step up to 3/8 or 1/2 depending on the gap. Once you put that down, then there is no need to add 1/4 plywood.


1

For sound insulation, there are multiple layers where you can tackle the issue, and the more you do, the better the result: Insulation between the joist bays. No vapor barrier needed since this is for sound, not thermal. This is going to eliminate the high pitched sounds like voices, more than the low thumping of walking that will transmit directly through ...


1

You could use Cork as a deadening agent or finished product, use it as a deadening agent and it would prevent any off gas issues. As Iggy said, you would want to insulate the joist bay's, however I don't think you want to pack them tight. If you pack a bay tight with insulation the sound waves use it as a vehicle and transmit each wave easier, a loose pack ...


1

Insulate the new subfloor in the joists below to thwart any condensation issues first, as much R-value as you can get in there. Other than that no, the "underlayment approved laminate" can just sit on the underlayment & you might be able to double or triple the planned underlayment, depending on the laminate manufacturer. However, Carpet on top of ...


1

I would glue and screw down the plywood. If you use hardy backer board I would use a dash patch or leveling compound on that before you set your tile. A good alternative would be to do a mud job on top of the plywood that would take care of the leveling problem. A mud job is tar paper stapled to the plywood with a layer of stainless steel mesh nailed to ...


1

I believe the point of underlayment in your situation will be controlling moisture movement from below. That is, you want a vapor barrier under the floor. Now, the underlayment can achieve other things as well, such as providing a "loose" surface for a floating floor (as discussed by @DMoore), or enhance sound deadening. I read your post and comments, ...


1

I would. I put underlayment for all engineered. I spend about .25 a sq/ft for my high quality rolls so not sure what you are looking at. The point of the underlayment for engineered flooring is to provide a surface for the wood to slide across (wood on wood gets stuck sometimes) and to decrease the noise between hardwood and subfloor. Imagining your ...


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