Putting Battens On Ply - Best Way

yop

Lads

Am attaching the 1.5" * 2" upstairs for the UFH, what is the best way to attach these, am thinking about using 3" screws straight onto the ply but the dad reckons that this might leave squeeky boards, an opinions?

Cheers

Farls

I'd go with screws....they will take out the squeekyness that nails would leave.

rooferPete

Hi Yop,

I presume you are cross lathing over the joists ? not that it matters much they have to be fixed either way.

Being lazy I would use a chalk line and strike lines where one side of the laths are running, then belt and braces I would run a line of wood glue centered on the lath.

Sit the lath in place and use a paslode nail gun with 75 mm nails if I'm going into the joist 70 mm if I'm just fixing to the ply.

2" timber is actually 44 mm so you should get a good enough bite with 70 mm nails, you could adjust the settings on the gun and use 60 mm recessed into the laths.

I am presuming 20 mm ply I think you can do harm to the ply by shooting in nails that can burst through by 20 mm, screws are real solid fixings 60 mm recessed should be enough if used with the wood glue.

.

yop

So the way to go would be 60mm nails and glue lads,

The laths will be running the same direction as the joists, but with the 20mm ply then there will be good holding

garyh3

What about using ring shank nails ?

rooferPete

Hi gary,

Paslode are ring shank nails, at least the ones I have are.

You have made a very good point especially as Yop is fixing into both the ply and the joists, ring shank are almost as good as screw fixings but a lot faster.

.

yop

Umm that is true, I also thought that Paslode nails are ring shank.... I have a nail gun off a geni but not sure if it would drive 70mm nails.
I might go down the screw route though.

thanks for yer help

qazxsw

Hi yop,

I've done this recently - (ufh upstairs over timber joists concrete infill that is)

Don't know how close together your joists are, but I was advised by by ufh company (alternative heating and cooling) to counter batten over the joists @ 14" centres as they maintained that that 16" centres wouldn't allow them to pack in the ufh pipes at a high enough density.

As far as I can make out the reason for the battens is three fold

1. to allow the ufh company to space out the pipes correctly
2. as a guide to screed the concrete
3. to allow fixing of timber flooring down the line

If I was doing it again i'd propose the following

• prop the joists with acros, especially any long spans
• lay light guage plastic in place anywhere there's going to be concrete
• place battens 6ft to 8ft ft apart making sure they were solidly fixed and 100% level
• mark out the 14" centres with spray paint to allow for correct spacing of the pipework
• cable tie light steel mesh over the pipe work, making very sure that the mesh and pipework were under the battens by using extra fixings where necessary. OR fix the steel mesh to the ply and cable tie the pipe work to it (Photograpsh at this stage - lots)
• pour the concrete, screed and float
• lay a floating floor down the line

I reckon the system above would give a quieter, stronger floor and that it would be structurally superior to the "batten" system.

I haven't updated my blog with pics of the ufh upstairs but hope to get around to it this w/e

yop

Gaz, I am a bit lost to what u did really,

U have exposed joists, is that correct?

You then put battens down, what use is 6ft apart?

You laid the pipes on what? Insulation I presume?

Then you put a mesh over the pipes and screeded this? Now u have a full screed upstairs onto which u can lay your carpet or timeber, is that right?

Our setup is going to be,

1. battens laid at 14" spacing
2. 25mm insulation between
3. battens notched to take the piping.
4. Piping laid
5. screed poured level to batten in landing, toilet and ensuite, bedrooms are left as I don't want a "storage heater" effect.
6. timber floor laid on battens in bedrooms.

Similar maybe?? bar you went with mesh

qazxsw

Sorry for any confusion caused :-(

firstly I said IF I WAS DOING IT AGAIN I actually used 14" spaced battens over plastic, over OSB but the results will need a bit of more work before I can lay floor boards :-(

Secondly I omitted to say that I sheeted out over the joists with 11mm OSB first, I was taking this as a given - my mistake

I also omitted to say that I cut 50mm kingspan insulataion to fit between the joists.

To run through my PROPOSED method again

Joists

• fit insulation between joists
• Sheet out with OSB3 / PLY
• lay light guage plastic in place anywhere there's going to be concrete
• place battens 6ft to 8ft ft apart making sure they are solidly fixed and 100% level
  
  a)I think it would be a lot easier to level a small amount of battens @ 6ft centeres than a large amount @ 14" centres
  
  b) it's a lot easier to get a level (concrete) pitch when the screeds are 6ft (or there abouts) apart than when they are at 14" centers because there's no way you'll get the battens level enough when they're that close - you're depending on the joists being level - and as mine were 9" x 2" NOMINAL my chippy laid them to be level for the Ceiling, not the floor overhead - i.e. any discrepencies between the height of the joists was "pushed" to the top - where the flooring will be :-(
• mark out the 14" centres on the plastic with spray paint to allow for correct spacing of the pipework
  
  (I suppose you could do this before laying the battens and adjust the batten spacing so they are laid on one of the coloured lines)
• cut the light steel mesh to fit between the battens
• Either
  
  lay the steel mesh ensuring its tight to the OSB and then cable tie the ufh pipes to it
  
  OR
  
  lay the ufh pipe work and cable tie the mesh to it
  
  either way make very sure that the mesh and pipework are under the battens by using extra fixings where necessary - lots of photos at this stage
• Pour the concrete and screed - To avoid being under pressure I'd recommend about one worker per cubic metre of concrete.

obviously you'll have to notch the battens and if you are laying the insulation on top of the ply you'll have to icrease the height of the battens to allow for this and stil get the desired depth of concrete.

---

Hope this helps and doesn't cause even more confusion

yop

No lads, cheers for clearing that up

Eve1

We are are similar to Yop in that are tf will have a ply floor laid down ontop of the joists. We are then going to put down our insulation. Do you have to put battons down, and fix the insulation in between? The reason I am asking is that are ufh is being installed on a mat, so the battons would only be as high as the insulation.

Eve

yop

Eve, we are using the battens are we are putting timber floor over the battens, u need something to carry the flooring,
We are screeding the landing and bathrooms upstairs,

Eve1

I know this is important to make sure the pipes aren't crushed while you lay the screed and to check the system is working correctly, but how is this done if your system isn't fully connected up.

yop

U won't crush the UFH pipes from what I have seen of them, they are as hard as rock. BUT maybe others may have experienced differently!

CJhaughey

Are the pipes Qualpex barrier? if so it usually has a black plastic armour around the pipe mainly to stop the qualpex being damaged if the concrete cracks.

Eve1

The system is called gabofloor, and it says they have to be pressurised. I must ask uhf guy if this is possible or if we have to have the entire system working before we put down the screed. Prior to us deciding to go with this system we were going to be using the battons as a guide for the screed as this is how my partner did it befrore. I know think it is going to be a difficult job and it would have been easier to lay the ufh ourselves.

qazxsw

my guys pressurised the pipes with air up to 8 - bar using a portable compressor run from a generator.

just needed to keep an eye on the pressure gague on the manifold to make sure it was maintained during concrete pour

It was allowed vary a bit as the temp of the air in the pipes would drop when the concrete was poured - but as long as there was no major decrease of say 3 - 4 bar things should be ok.

patrido

the reason for the pressure is to check for leaks before pouring the screed. and then to quickly show you if any damage during the pour, such as someone puncturing a pipe with a shovel.

i believe you need to test up to 6 bar initially, and leave pressurised to 1 bar during the pour, though different suppliers will have different recommendations.

it can be done with air as qazxsw said, or with water by connecting a suitable hose. either way you only need the pipes connected to the manifold - you don't need the whole system connected and working. of course if you use water, you have to fill the system, purging all of the air before pressurising.

as the winter is approaching, it's probably worth mentioning the story i heard about a guy who pressure tested his ufh with water, and forgot about it for a couple of days during cold weather. the water froze and the system was ruined. apparently he couldn't afford to dig it all up and do it again, so now he has radiators.