It seems like engineered wood flooring (3/4 inch) would be stable and would work well with radiant heat (under sub floor). Does anyone have any experience with it? I’ve seen engineered bamboo flooring in 3/4, but everything else I’ve seen is 5/8 or less, or floating systems. I want to nail it down. I can’t find any info. Help, please.
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What type of radiant heat floor do you have, ie. retrofit, new under the subfloor, or in the slab?
I'm putting in Wirsbo tubing under the floor in a new house under construction. If I had to do it over again I'd probably spend the bucks and use the underlayment that has the grooves and heating plates in it, but I have all the materials and am about to install the tubing and the aluminum plates from below.
The Wirsbo manual I saw showed 8 staples per plate. Now I start hearing horror stories about the plates making noise as they expand and contract, so don't make them too tight. Then a guy who followed that advice and attached them using two screws per plate said he hears them banging around as people walk across the room. Any other bright ideas that can help or simply push me over the edge will be appreciated.
Engineered, or ply-structure flooring, works extraordinarily well over RFH.
I won't nail a lot of the half-inch or thinner floorings, as the nails/staples can make mincemeat out of the tongues, and if the fasteners aren't set perfectly, in a flooring that thin often times the fastener head (or even the material displaces from the tongue) can displace the groove, causing slight bumps in the flooring. Some are subtle enough so you can't feel them when you walk on the floor, but with a low-level light coming across the floor they're quite visible. All that said...some manufacturer's advocate nailing their thin engineered flooring, but you need a conscientious installer to do the job.
I have nailed 5/8ths bamboo and it turned out beautifully. Bamboo does take a bit of tweaking with the pneumatic pressure, as it's brittle and can splinter if you just start banging away at 120psi.
The best bamboo I've come across is from TimberGrass.
Check out Sika's AcouBond method for glueing the flooring to the deck. There is a lot of radiant underfloor heat being used here under wood flooring. With conventional naildown solid wood, we all just ignore the gapping that occurs when the floorboards shrink during the heating season. But this Sika method allows the whole floor to float, and is the only thing the good guys I know will now use with solid wood. I used an engineered prefinished product, a non-Sika gluedown, and have had no problems. Nailing over that tubing would make me nervous.
So what's this Sika anyhow?? I tried to find out about it, even went to Sika's web site, but couldn't find anything called acouBond. The web site I was on was for a company called Sika that made industrial adhesives, but nothing called AcouBond. Any ideas where I an get info??
Go to http://www.edelweissflooring.com/sika to see about the system.
Great link...interesting enough to look in to for future applcations.
Regards, Mongo
I am about to install an engineered oak floor using the "Sika AcouBond" system. Has anyone out there used this system before? If so I would like to hear any suggestions, feedback, helpful hints. The installation Guidelines booklet seems pretty thorough, but it would be nice to hear from someone who has actually used it.
Thanks, Dickduck
Gene,
In Oct. you wrote about seeing a crew using Sika's AcouBond to glue a floating floor. I have two questions. You said it had a "neat cushion feeling". Hmmmm. I'm trying to understand what that means.
The only floating floor I've walked on, that I know of, was at HD on Pergo or some other such material, and it felt and looked awful - my opinion. Like a sheet of wall panelling laid on thin carpet pad. The only floors I've installed have been strip oak, yellow pine and a real cheap soft pine - in an old Cape cod house. All had a neat solid feeling.
The other thing you mentioned was you were using an engineered prefinished product. I'm looking for info on this, but I really like a full 3/4 thickness. When I try to find "engineered" all I come up with is bamboo or some 1/2 inch material.
It's getting close to "decision time" on my flooring, so I'd appreciate any and all advice. Thanks in advance.
The floor I saw laid was solid wood. Kiln-dried 3/4" x 4 1/2" select cherry, tongue and grooved, end-matched, was put down over the Sika Acoubond 5mm mat, with the Sika glue bonding the floor to the substrate (3/4" plywood over 16" centered joists) through the obround slots in the mat. The floor was sanded and finished after. Below the deck is a hydronic heating system, with tubing stapled to the bottom face. The Sika system was chosen because it allows the floor to move with moisture change in the wood, exactly as needed because of the in-floor heat. See specs by going to http://www.edelweissflooring.com and looking for "installation systems." The Sika specs permit solid wood up to 1-1/8" thick and "engineered" wood flooring as well. The "give" that the floor exhibits comes from the compressibility of the 5mm mat. Thicknesses of 5mm and 3mm are available. It is called "Acou" because of the wonderful reduction in sound transmission that the mat offers. If you are one floor below, the footstep sounds are deadened as well as for noise from stereos, TVs, etc. Material costs for the Sika system run about $1.25 psf. I plan to use it with a solid wood floor over a slab with in-floor heat, to be done next year.
Gene,
I'm about to use the Sika ststem to install my flooring over a plywood subfloor with the hydronic heating stapled below. Just wanted to let you know that I paid over $2/ sq ft, so if you found it at $1.25 that's pretty good. Where did you get that price?
Dick
I was quoted directly by Eiger International, Telluride, CO, the stateside distributor. I enquired for 1800 sf in both the 3mm and 5mm, and got a quote that worked out to about $1900 for 3mm, and $2500 for 5mm, mat and adhesive included in each number. Freight adds about $275. You will need some expendable tooling, specifically the v-tips for the adhesive guns. They sell all that stuff. Did you do the job yet? I am anxious for some feedback.
Edited 4/10/2003 9:14:51 AM ET by Mr. Micro
check out http://www.junckershardwood.com, solid wood floor that can be floated with their clip system or nailed. the clip system was originally invented to use with radiant heated floor systems in europe where it is very popular
i have used this product and would use it again
Be careful,
We built a house 2 years ago. Installed Award Engineered Flooring. It is installed as a floating floor over a pad. The boards are T&G and glued together. The installer had to leave room for expansion around the edges of the room. Our heating system is Forced Hot Water (Radiant Heating) in the floor. The water tubes are stapled to the subfloor and covered with 1.5 in. of concrete slurry. The sytem is completely noiseless and the floor stays nice and warm.
Pitfalls are having poor installers and poor system design. You need true professionals for both functions. You need an experienced engineer to design the system and the best installers that have experience working with the flooring manufacturer before you undertake this direction.
The underlfoor installation is less efficient, but more forgiving. You attach the tubing to the bottom of the subfloor with special staples for that purpose. You must then use heavy insulation with moisture barriers under the tubing to hold the heat. The more the better. It should not make any noise. My pastor installed his own doing this and it works fine. You will still need help installing the plant, pumps, valves and manifolds so get a system designer to help.
The system should offer you years of quiet, dust free high efficiency heating.
Mike