Installing ST panels on an Insulated roof

[pmagowan]

I am about to replace my roof and it is going to have 150mm of insulation above the rafters (EPS).  I have a few questions about preparing for ST installation.  The standard install seems to require pushing a strap under the slate and attaching it on the inside.  This is obviously not possible in my case.  Do I attach a could of fittings to the counterbattons prior to slating?  Is positioning very important?  Do i drill a hole for the pipework after re-roofing or do I install a grommet?  Will the pipes get too hot for the insulation (EPS, polystyrene) and if so how do I work around this?

Any ideas welcome,
Paddy

[kalas666]

Hi Paddy, 
What kind of roof slates do you have? and have you started installing the celotex yet?

If you haven't started insulating yet the you can still push the straps through and screw to the sides of the rafters.  You can also leave a gap between the celotex and a rafter to run the pipework down to the wall then pack the space with loft insulation.

If you have already installed the celotex you will have to lift the tiles on the roof and find out where the rafters are, then screw the straps to the top edge of the rafters.  Your pipework will then have to run externally up to the ridge or down to the eaves before entering the property.

Chris

[Richard Owen]

Here's how I did it: www.navitron.org.uk/forum/index.php/topic,3388.60.html

Pages 4,5 & 6 are the appropriate ones. I think.

It's mostly drivel.

[pmagowan]

Thanks Guys.  I am only at the spec stage and the roof is unaltered.  I would prefer not to bridge the insulation with the straps as it would be hard to make them airtight and it is thermally poor.  The counterbattons are 50x50mm.  I had thought about attaching the brackets to the counterbattons in the appropriate spots while slating.  Also the EPS insulation could be replaced with foamglass or similar at the spots where the pipework penetrates.

For some reason I can't see your photos Richard.  I will try later on my home computer. 

Thanks.