Solid wood on concrete slab

[JoinerMike]

Hi all
Hope you are all well.
Im just after some advise and helpful tips.
I am going to be laying a solid wood flooring onto a concrete slab. I am doing around 100sqm running into 4 rooms. I have decided to do this using the sleeper method using 2"x1" batons. I was thinking of doing it in this stage if you have any advise or tips please inform me
1) Re-check moisture content of slab again prior to fixing.
2) Lay blue visqueen sheeting on floor running up the walls 4" and taping with mositure proof tape, overlapping sheets by 6"
3) Lay 2"x1" battons 250mm centres overlapping instead of buttuting up end grains of 2 battons. Fixing with plugs and screws. Laying width of room.
4) Lay polystirene inbetween battons.
5) Fix flooring length ways using 40mm/35mm tounge tite flooring screws leaving expanson gap around all edges and cutting in doorways

If you have any advise I would be very greatful to recieve it. What expansion gap do u suggest, should i put in expansion joints at doorways and if so how?
I have choose batton method as its cheaper and the height isn't a problem as all of down stairs is getting done and all exterior doors have the space under the door for me to do this

 

[WoodYouLike]

Gaps depend on the width of the rooms: for every 1 meter wide leave 4mm gap, with a minimum of 10mm.
so rooms of 4 meter wide: 16mm gap with solid Oak.
(Wood-Engineered flooring Oak; 10mm if rooms not wider than 5 meter)

 

[mups1]

Very sorry to butt in on this thread but I am also considering going down the same route. Some previous threads advise against screws so I too would be interested to hear of anyones experiences with "tongue tight" screws, which are recommended by Elka flooring but available elsewhere. Also I wonder whether it is necessary to fix the battens to the slab? - I have previously laid a floor on battens as a floating floor without any problems.

 

[JoinerMike]

Hi mupps1
to help you on your enquiry I have used tongue tite screws and secret nailed floor loads of time and had no problems with them. But i only use these on solid wood laying on a wooden floor. What i would do is lay plywood and screw that to the floorboards and the tongue tite the solid wood to the floor every 200mm approx. Kepping in about 5" from the edges. The disadvantages are the time it takes to screw a screw in compared to banging in a nail and the expense as I get them for £5 for a box of 200. Normally a box lasts about 8sqm. But it is cheaper if u don't have a gun to secret nail as them things cost over £400. I have layed these floors years ago using tounge tites and 100% of them floors are still fine. I am just starting to dabble in laying onto a concrete sub floor hense the post. Any questions you have about laying your floor ask and ill try my best to help you. Im just useless when it comes to concrete sub floors lol

 

[JoinerMike]

Thank you WoodYouLike for your time and advise.
sorry to bother you again, do my stages seem alright or would you do it differently?

 

[WoodYouLike]

If your mind is set on battens, can't see anything wrong with the stages.

However, we would never screw a floor: too much risk of splitting when your humidity reduces - winter, heating season - and we would, if your concrete floor is level install the floor using the floating method if your new floorboards are at least 10mm wide. But that's us, we hate waisting extra materials, time and effort

 

[mups1]

Hello again and thanks for the advice JoinerMike. Butting in again, very sorry.

Woodyoulike, would you say that nailing is better than screwing the floor? Are portanails designed to permit movement in the floor more than screws and so less risk of splitting if shrinkage occurs? Or does it make no difference? What puzzles me if there is such a risk with the screws is why do Elka promote them.

The other thing that puzzles me is that if floating the floor above the sub-floor is OK for solid wood (as opposed to engineered wood) why do the big companies consistently advise against it? I presume there must be some risks? Do you know what they are? I still may opt for this approach as I like the idea of giving the floor freedom to move, especially as my boards are 150mm wide. Cheers.

 

[JoinerMike]

Cheers WoodYouLike
I am still open to options. But i have done a few on concrete subfloors using the floating method and they have all moved. (Gaps appearing in the middle of a row of flooring etc and expanding more on one side of the room from the other creating it to twist. Maybe i was doing it wrong. I layed visqueen again over lapped and up walls and used tape. Fibreboard underlay then flooring on top and glued tongue and groove. What glue do you use (Junkers? etc) and how much is it? What sq metre coverage do you get from one tub? I'm the same as mups1 everyone I've spoken to has suggested that floating floors are used only for engineered flooring not solid oak etc. My boards are wider than 100mm.

 

[WoodYouLike]

mups1 - T-nails are specially made for wood flooring, pin downed in an angle and if down properly with all other circumstances checked it will allow seasonal movement, as with floating.

We are aware Elka is promoting their new type of screws for flooring - we have never worked with that and I don't know if it works properly, haven't heard good or bad stories from colleagues. Like 'click-systems' and other 'inventions' everyone is trying to get market share and need to 'innovate'.

Most major manufacturers we know now state their wider solid floorboards can be installed: nailied, glued and floating - sign of the times, again of market share and experiences of professional installers floating solid floors without problems.

Joinermike: gaps appearing in the middle of floating floors normally indicate the T&G's have not been properly glued: you have to glue the whole length of the grooves, not just drips and drops.
We use normal PVAC woodglue, Lecol mostly. How many square meters? Depends on the width and length of the boards (more or fewer grooves to glue) and the size of the groove really. On average 15 sq m per flask of 750 gram.

 

[mups1]

Thanks WYL. Commendable public service you provide!