Tin Soldier

Velux onto sarked Roof

Recommended Posts

Morning

 

another stupid question

 

I'm looking to install two velux windows onto a roof with 22mm sarking boards over 25mm battens.

 

the velux windows have a gutter at the top, run at a slope.

 

The instructions show the cutting out of batten/counterbatten so there is none, with the gutter sitting directly on roof screwed into rafters.

My roof makeup is sips panel, 25mm batten at 600 centres and then 150mm wide sarking boards.

 

so without being up there and trying it out I'm struggling to see what to do here. do I put the gutter just on top of the sarking board, which means its higher up the window than shown below,

 

do I remove the sarking board/part of it to attached to the batten below which would be at the same depth on the window as picture below,

or removed sarking board and batten and have it at a lower depth.?

 

confused. help appreciated.

Untitled.png

Share this post


Link to post
Share on other sites

Have you got the correct flashing kit?  Sarking and no battens on the sarking to me means slate nailed direct to the sarking. I suspect you might need a different flashing kit.

Share this post


Link to post
Share on other sites

The bit of angle iron is slipped underneath the roof felt so any rain that gets that far runs down the felt hits it and then runs of to the side of the window. That's why it's cut at an angle.

Share this post


Link to post
Share on other sites

I hope I've got the right flashing,

 

Coupled Slate flashing, 100mm centre gap - that image above is taken from the installation instructions.

 

 

Share this post


Link to post
Share on other sites

surely you're fitting velux to sarking as opposed to velux to battens? there should be instructions for fitting to sarking

Share this post


Link to post
Share on other sites

The diagram shows the roof as being batton  but your roof is sarking ? I would double check with velux that your starting with the right kit. Its really straight forward as everything should be self explanatory...... I have done 3 into sarking a few months ago, will see if I can find the info. 

Share this post


Link to post
Share on other sites

I am curious as to why your spec has the sarking over the battens. Our TF warm roof is sarked with the roofing fabric directly on the sarking and the counter battened and battened on top of that and then slated.

 

We have Fakro room lights and you need to choose the frame model and mounting kit depending on the covering profile, so you need to choose the correct combination for a top sarked profile.  I assume that the same is the case for Velux.  Your figures are for a batten over sarking profile.

Share this post


Link to post
Share on other sites

Roof Panel Makeup from top to bottom.

 

Slates

Membrane

Sarking

Battens

Fabric

SIPS Panel

Share this post


Link to post
Share on other sites

I would have imagined it would have been:

Slate

Batten

Membrane

Counter batten

Sarking

Fabric? Not sure what you mean here

Sips panel

Share this post


Link to post
Share on other sites

Without battens to fix the slates to, how will you know you are not running out of true/parallel?

I presume you have to ping lines on the sarking and hope they line up with the battens underneath.

Share this post


Link to post
Share on other sites

its Scottish roofing practice to nail slates direct to sarking board.

Share this post


Link to post
Share on other sites
4 hours ago, bassanclan said:

Without battens to fix the slates to, how will you know you are not running out of true/parallel?

I presume you have to ping lines on the sarking and hope they line up with the battens underneath.

 

That's what sorts the men from the boys??

Share this post


Link to post
Share on other sites
On 24/05/2018 at 09:25, Tin Soldier said:

Roof Panel Makeup from top to bottom.

 

Slates

Membrane

Sarking

Battens

Fabric

SIPS Panel

Intrested to know what the fabric is as on a standed Scottish roof the breather membrane goes on top of the sarking, that way if you get a leak then the roofing membrane is there as the emergency layer. My roof is 

slates

membrane

22mm x 150mm sarking boards  

‘main roof timbers  

 

i dont have battens as the slate is reclaimed and vary   in size (a traditional style) from the biggest / longest slates at the bottom of the roof and the smallest slates at the top. 

There is then a 50mm ventilated gap below the sarking before the insulation. 

 

But as usual there is a dozen ways to skin a cat and I am just interested in your build up and the solution to the velux installation. 

 

 

Share this post


Link to post
Share on other sites

so, the SIPS panels company threw up the panels and wrapped the house in nilvent on walls and daltex roofshield on Roof

 

I didn't expect membrane to be put on at all so when questions the manager said

 

Yes membrane is on, but you'll have to batten at 600 centres to leave a ventilation gap, then sarking board on top.

I've put a second layer of membrane on the sarking (or I will once finished) as the roofshield has plenty holes it in where the lifting straps etc for the roof panels were cut off.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now