Batten size and fixings

[Pete]

I will be using a Parex render on moisture resistant backer board (weight 27kg per 8x4 sheet). I have conflicting advice telling me that 25 x 50mm battens will be suitable using stainless steel screws 6.0 x 90mm spaced every 500 mm from timber frame supplier. Parex say 25 x 50mm battens are a minimum and would prefer 38 x 63mm battens using 5.0 x 75mm s/'s screws spaced every 150mm. This would give a fixing of 25mm into the actual timber frame after a 38mm batten and 10mm panel vent board. So the thinner batten has a larger screw with wider spacings and thicker batten shorter screws with less spacing between screws. What have other people used for their battening?

Parex say the larger batten is kiln dried and more stable but trying to keep it dry before render is applied will not be easy.

TIA

Edited October 5, 2017 by Pete

[MikeSharp01]

Have you got that quite right @Pete you say that the 90mm screws are spaced at 50mm and the 75mm screws are spaced at 150mm. 50mm spacing must be overkill and going in 90mm when you have 35mm of mounted material - so 55mm into the sub strata while the other one only have 25mm seems too little or in the former case are the battens held on independently of the backer board? In which case less of a problem. 

 

In the end you need to go with what parex recommends as anything less might lead to problems if there is a problem - if you get my drift.

[nod]

13 minutes ago, Pete said:

I will be using a Parex render on moisture resistant backer board (weight 27kg per 8x4 sheet). I have conflicting advice telling me that 25 x 50mm battens will be suitable using stainless steel screws 6.0 x 90mm spaced every 50mm from timber frame supplier. Parex say 25 x 50mm battens are a minimum and would prefer 38 x 63mm battens using 5.0 x 75mm s/'s screws spaced every 150mm. This would give a fixing of 25mm into the actual timber frame after a 38mm batten and 10mm panel vent board. So the thinner batten has a larger screw with wider spacings and thicker batten shorter screws with less spacing between screws. What have other people used for their battening?

Parex say the larger batten is kiln dried and more stable but trying to keep it dry before render is applied will not be easy.

TIA

The 50 x 25 treated batterns are fine I think kiln dried is overkill 

Thiugh I would space your (Stainless) screw centres at 150

I would make sure that you have a minimum of 30 mil fixed into the TF 

The jobs that I've done with Parex and other render systems may well have been battened week or months prior to us arriving onsite

So as you have already pointed out

Keepibg them dry would be impossible 

 

Hope this helps

  Gary

[bassanclan]

I would be very wary of varying from the Parex specs. They will use any excuse to get out of any warranty issues, including installation by non Parex approved contractors etc.

There will be a data sheet for the render board.