Non-Toxic Glue for Engineered Wood Flooring
This topic is giving me more grief than the complicated stuff!
Manufacturer strongly recommends our 8″ wide planks (5/8″ engineered wood) be installed with glue-down method. Locally everyone does glue and nail/staple which the manufacturer also allows, or floating. Climate is 6B, dry.
And it’s almost impossible to source fairly non-toxic glues (like the Bona 850/851). Full glue down is easier to get (ie Berger-Siedal Berberbond M1, and Mapei Ultrabond Eco) but there is one option for tubes for glue and nail I’ve found I could order from the UK that is on the manufacturer’s recommended list (Sika 52 WF).
First I need to solve the issue of whether full glue is better than glue and nail, or vice versa. Any thoughts on that? Our climate is dry with large delta T’s. But my house is super insulated PH, the crawlspace is house temperature. Then again we are allowing sun in the numerous windows and that will warm up the floors.
If anyone has product suggestions they like, I’d love to hear them. I will sort through to find ones that are low toxicity and don’t have any fungicides. (I am building the house to be mold-free and fungicides are actually worse for people who are mold sensitive. And I have cancer so the VOC’s have taken on new importance.)
The substrate is plywood.
Thanks
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
The 8 inch wide choice is why the installers want to glue it down if you pick something 5 inches or less you could likely skip the glue.
Seems to me a pre finished hardwood would have much less VOCs as the engineered has a ton of VOC built in the factory of unknown quantity and quality. The prefinished just has a thin surface layer that off gassed in the factory’s oven and the weeks if not months it spent in the warehouse.
Walta
Thanks. The floors are all greenguard certified super loc VOC (the finish and the core), and were delivered 6 months ago (although palletized so not sure how much off-gassing is happening.) Still I'm not worried about the floors.
I don't want to skip glue. I want to understand the trade-off between full glue and glue + nail.
The engineered planks are not going to move very much with either temperature or humidity changes. For wood products, humidity driven expansion is far greater than temperature. If your house is pretty consistent in humidity, you won't have any trouble with any fastening system. All-glue systems will work fine, but make sure the installers follow the adhesive manufacturer's installation instructions exactly. All of the glue failures I've seen were related to not following the instructions. FWIW, I like both Mapei and Sika products though I don't have specific experience with the ones listed.
Thanks, that's helpful. And in re-reading the manufacturers specs, they claim to have the most stable core design in the industry. Marketing puffery maybe but it's probably safe to assume it's decent.
We're putting in 5 1/8" engineered flooring. Preverco Flex 19 Maple to be exact. They recommend glue assist for 5 1/8" and up. That's glue and nailed. The glue is a 1/4" straight bead 1/2 from the tongue.
https://preverco.com/wp-content/uploads/2021/08/Fastener-Schedule-2021-04-23.pdf
I located Bona 850T in the sausage tubes from a company in Grand Rapids, MI. It's not in stock but they are getting pallets every few weeks. Not sure how soon you need it or how close you are to central lower Michigan.
For 8" wide planks, you might want to go full glue though. Or maybe a second 1/4" bead or larger pattern on the plank?
Thanks. We have 3000 sf and it's hard to determine the amount needed because they are pretty vague about coverage. The quotes are estimating 100 for glue+nail. Do you understand why full glue might be better for 8" wide? Everyone in my town does glue+nail, but while that is supported by the manufacturer they suggested full glue would be better. But nobody can explain why one is better than the other.
Hi Michael, Could you give me the name of the company in GR?
Thanks!
https://energyst-solutions.com
I received 8 cases about a week ago. Call them up. They are very helpful. If there is a wait-list they get a pallet in pretty frequently.
The guy where I got the glue said 200-250 sq/ft a case (12 sausage tubes). I have 8 cases coming for 1,600 sq/ft. Probably overkill but don't want to be short. They buy back extra within 30 days too.
I'm not a flooring expert but they start to recommend glue at 5" planks. Assuming for a better hold and less side to side movement.
At some larger size you need the next level above one 1/4" bead. Maybe that's 8". Full glue I'm assuming would allow zero movement especially side to side, squeaks, etc....
So you can put 2 or 3 1/4" beads down for more glue, but at some point maybe it's just easier to go full glue.
8" is a huge plank. It low VOC is a priority go with a smaller plank width. If you went 3" you wouldn't need glue at all. To me 5" is a good balance of stability and a more modern look.
Think of it as shower tile and the smaller the tile the easier to match the shower pan. Small floor means less uneven area to cover. Full glue also acts as this rubbery leveled mat under your floor Which is going to help a lot.
If I had unlimited money and a willing contractor I probably would have went full glue with my 5 1/4". Or would have at least thought about. I'm happy with the glue and nail though too as it's recommended by contractor and manufacturer.
Thanks, I appreciate the input. The floor was bought a long time ago, and I do love it and it is low VOC itself. Most wood I looked at was too rustic for my modern house.
https://craftfloor.com/collections/stylewood/
I just don't understand holding power of glue vs nail and glue. Seems like nails hold down well too. And I think they use a serpentine although I have seen the beds on the edges as well.
They hold down well but rely on a very flat floor. Any voids over that 8" width could cause squeaks and even lateral movement on a really bad floor.
My understanding is the full glue fills the voids so it's totally level and dries to a rubber like texture with allows for contraction and expansion. Either through pressure from walking or humidity changes.
Just my thoughts after looking into it for a while.
What engineered hardwood flooring - the manufacturer- did you purchase? My daughter has cancer & we have to go w engineered in her bedroom - to match flooring in hallway.
I’m not thrilled w Bono products, what glue did you end up going with? Looking for Greenguard gold. Is Bono the only option?