Small Cabin

Small Cabin Forum
 - Forums - Register/Sign Up - Reply - Search - Statistics -

Small Cabin Forum / Cabin Construction / Best flooring over slap with radiant heat
Author Message
MJR0311
Member
# Posted: 14 Feb 2020 00:11
Reply 


I’ve heard opposing arguments over the best flooring over a slab on grade with radiant heat inside the slab for my north Minnesota future home.

Wood floors are fine
Wood floors are bad
Wood keeps the heat down in the floor
Wood floors fail
Hickory floors tend to fail
Vapor barrier
No vapor barrier
The glue is the vapor barrier

Of course every floor manufacturer I ask swears theirs is fine for this.

Experiences?

Steve_S
Member
# Posted: 14 Feb 2020 04:40
Reply 


I have 12mm Laminate flooring on foam installed per manufacturer specs, no issues. I have Ceramic tile as well straight on the concrete slab, no problem.

I keep the radiant heat at 24C / 75F.

Those temperatures are nothing unusual not too hot, too cold … humidity is moot - normal to the home not more or less. absolutely LOVE IT RADIANT HEAT and my bones agree too. Someone has been telling you wives tales, echoed by gullibles who believe that nonsense... hint, the world isn't flat nor square.

Brettny
Member
# Posted: 14 Feb 2020 07:32
Reply 


You can't put real wood on a concrete slab. Wood moves, concrete dosnt.

Steve_S
Member
# Posted: 14 Feb 2020 08:24
Reply 


Quoting: Brettny
You can't put real wood on a concrete slab. Wood moves, concrete dosnt.


Yes you can, it's called using sleepers to affix the wood flooring to and it's done so it has a little float at wall edges to prevent any potential buckling.

MJR0311
Member
# Posted: 14 Feb 2020 09:08
Reply 


Quoting: Steve_S
Yes you can, it's called using sleepers to affix the wood flooring to and it's done so it has a little float at wall edges to prevent any potential buckling.


What do you mean by sleepers?

Brettny
Member
# Posted: 14 Feb 2020 09:18
Reply 


Using sleepers isn't attaching it to the concrete.

Sleepers are basicly furring strips. It's a crappy way to apply a floor esp with radiant heat.

Steve_S
Member
# Posted: 14 Feb 2020 09:28
Reply 


basic sleepers on concrete slab

Alternate method

Steve_S
Member
# Posted: 14 Feb 2020 09:29
Reply 


Quoting: Brettny
It's a crappy way to apply a floor esp with radiant heat.

OKAY... find credible, verifiable & tangible articles to support that nonsense.

Oivey… no wonder many of us left this forum.

MJR0311
Member
# Posted: 14 Feb 2020 10:18
Reply 


Thanks for posting what you meant. I’ve never heard of that ever being successfully done though. I think having a pocket of air like that between a slab and flooring could turn into a condensation/ radiant heat nightmare not to mention the hollow sound. Engineered hardwood or wood look tile might be my best bet.

Aklogcabin
Member
# Posted: 14 Feb 2020 12:37
Reply 


Yes to SteveS . Kinda tired of seeing negative opinions when others don’t have all the facts. A cheap shot is a cheap shot.

MJR0311
Member
# Posted: 14 Feb 2020 14:13
Reply 


Thanks guys for all of your input. No need to get pissed off at each other over my stupid questions. So far this seems to be a pretty good place to get ideas. Cabin fever is starting to get to us all! No pun intended.

Steve_S
Member
# Posted: 14 Feb 2020 15:24
Reply 


MRJ if you have a properly done slab which is thoroughly cured and still concerned about moisture then something else is up. I have been running with Radiant Heat inside a properly done FPSF Slab and never once had any dampness issues. My floors are Laminate on the correct foam, Have had to go and pull some up, still dry. I have some Ceramic tile mastic'd to the concrete as well no problem.

Floating pre-finished hardwood flooring can be done directly to sleepers or to ply, mounted to sleepers, the only trick is to leave 1/4" at the wall edges (cover with baseboard) for expansion / contraction. But good flooring like Bruce Hardwood won't have issues.

I've likely laid over 1/2 million square feet of ceramic tile and same for assorted hardwoods when I was a flooring installer. IF you want opinions and verification, look at how commercial installers do it and ask those who live with it and have done so for years.

Everything you get on the internet is an opinion so take it how you will.

MJR0311
Member
# Posted: 14 Feb 2020 15:38
Reply 


Thank you Steve. How thick should sleepers be? I've already framed up walls/doorways planning to put down 1/2-3/4" flooring. I don't have much room to raise the floor above the slab.

My slab is cured (12 yrs old) w/no issues. How well will radiant heat transfer through to the entire place (1800 sq feet) through the wood floor with the gap underneath?

snobdds
Member
# Posted: 14 Feb 2020 16:04 - Edited by: snobdds
Reply 


Brettney is exactly right, sleepers on a radiant floor defeats the purpose. The flooring on a radiant floor needs direct contact.

Sleepers on a non radiant floor is fine.

I thought this was common knowledge, but obviously not.

Brettny
Member
# Posted: 14 Feb 2020 16:21 - Edited by: Brettny
Reply 


If this is mostly a weekend place I wouldn't even use The radiant unless your keeping it at temp.
Also do you know If there's insulation under the slab?

MJR0311
Member
# Posted: 14 Feb 2020 16:25
Reply 


It’s not a weekend place. The radiant heat isnt going on until we’re ready to live there full time. That’s a long way off. Still need elec, well, septic etc

ICC
Member
# Posted: 14 Feb 2020 17:37 - Edited by: ICC
Reply 


Brettny, there are always things that should not be done in some places or under some conditions. But a blanket statement that you can't place wood over concrete is not accurate.

Assuming the concrete is well cured, flat and in good shape; tape a square (at least a foot square) of poly sheet on the bare concrete slab floor. Tape the edges down tightly. Leave that sit 24 hours. If there is condensation then do NOT do a wood floor. If the plastic remains clear then go ahead and do wood if that is what you want. There are different ways to do the installation.

Personally I love ceramic tile floors.

Steve_S
Member
# Posted: 14 Feb 2020 17:57
Reply 


Unless you put a thermal reflective thing between the concrete & air-space-wood the heat will be absorbed and released through the floor,... wood is also thermal mass.

You can use 1x6 kiln dried SPF for sleepers IF staggered and masticed to the floor (not heavily) then a layer of poly then floor. This is NOT The best way...

Better to use 2x4 Dry & Straight with a little mastic, still staggered & with poly over the top.

IF you want to do it another way. 1x6 staggered with 3/4" T&G Plywood OR OSB Subfloor for bathrooms, then wood finish over that.

two reasons for the plastic, 1) bugs... yes, bugs, 2) if you have a spill you do not want it to hit the concrete and if there is any condensation it protects the wood above. 6mil is fine, use accoustiseal on the laps of plastic or Red Tech tape (the stuff used for house wrap).

As you've had the place for 12 years, you know how the house will warm up everything, even the walls & furniture. The same goes with flooring.

I understand the Thermal Dynamics and the short comings from Radiant Heating but wood floors isn't one of them with few exceptions, mostly related to poor installation BUT occasionally, someone uses not fully cured & dried wood which can split, crack, twist etc... as soon as it is warmed. Remember that 70-90F isn't risky to anything.

mj1angier
Member
# Posted: 15 Feb 2020 08:27
Reply 


Unless you are set on plank floors, engineered floors do well on concrete. Also epoxy coating look great too. We have epoxy in our basement and in our vet hospital.
Here is our basement:
floor.jpg
floor.jpg


toyota_mdt_tech
Member
# Posted: 15 Feb 2020 18:39
Reply 


I would think a laminate snap together, no nail or flue type engineered floowing, 8mm thick on the floating foam pad woudl work great. Collect the heat from the radiant floor, allows for floating. I have seen concrete ground and colored to look like granite. Pick a nice color, looks great.

ICC
Member
# Posted: 15 Feb 2020 19:07
Reply 


Quoting: toyota_mdt_tech
I have seen concrete ground and colored to look like granite. Pick a nice color, looks great.


I forgot that a neighbor (a rural neighbor = 5 miles drive) has a stained concrete floor. Looks very good.

Your reply
Bold Style  Italic Style  Underlined Style  Thumbnail Image Link  Large Image Link  URL Link           :) ;) :-( :confused: More smilies...

» Username  » Password 
Only registered users can post here. Please enter your login/password details before posting a message, or register here first.