Roof questions

[owdgit]

Hi, I only found this site after I'd already done some of the work so don't SHOUT at me.
My house is a late 50's early 60's semi with Marley modern tiles and felt underneath.
After a major storm a leak occurred which went through to a ceiling (insurance would not pay out as they said it was wear, tear and poor maintenance! all though they will repair the bedroom).
On investigation there was a hole noted in the underfelt around the area of the leak.
The roof was severely encrusted with moss and lichen so I power housed it all off which showed up several broken tiles.
I have now replaced these and some others showing wear and the batons and underfelt in the areas affetced.
My questions are: -
Is it worthwhile coating the roof tiles with something like Thompson's water seal?
I would like to put insulation boards (celotex or kingspan type) between the roof spa's/rafters or whatever you call them as I am boarding the whole of the loft space to allow improved storage. Is this type of boarding ok? i.e. does it still allow the roof area to breath or will it prevent moisture dissipating? And is this a good price? Was thinking of the 40mm
http://www.bmdinsulation.com/insulation-special-offers.html.htm

Thanks.

 

[^woody^]

Thompsons will be no use at all

Interlocking tiles will crack on the interlocking runner section and so it is important to repair holes in the felt, and no just rely on the tiles to keep water out

If you have no insulation at ceiling level, then there is a good chance that humid air will enter to cold loft and condense on your celotex and make the roof space damper than it should be. So if doing this type of insulation, then really you need ventilation at eaves and ridge to let air pass through the entire roof space

However, unless forming a habitable room, it is a waste of time (and money) to insulate at rafter level as you are just letting heat escape into the loft

 

[owdgit]

Thanks woody, we do have insulation at ceiling level, I shall be boarding on top of that and that is why I wondered if it was prudent to insulate above this area as well. The soffits have ventilation as they were replaced a couple of years ago, which is when some of the tiles may have been damaged, I have repaired the felt at any damaged area, just waiting for some rainfall to test it (not that I want rain you understand).
I did think the Thompson's was maybe a little uneccesary but thought it worth asking the more experienced than myself.
Good forum this.
Thanks for any replies.

 

[owdgit]

Whats the consensus on the extra insulation?
Although the felt has been replaced in the damaged areas there are the 'remains' of some tears inside the loft. I thought the insulation board would help keep the torn bits in place by shoring them up. Is there a better way of 'sticking' up this torn felt?
Thanks.