Installing ventilation on a cement fibre (Chrysotile!) slate roof

[RandomGrinch]

Hi, I wonder if any of you wise people can help?
I have a mid terrace house and have had the builders in to put a firewall in the loft (the loft space was open for most of the terrace).
As a consequence of building the wall, the loft has very little ventilation and is getting stifilingly hot!
I was going to fit a dry ridge, extra soffit ventilation and slate vents, but then found the slates contained asbestos.
So, would anyone recommend still carefully fitting the dry ridge and vents?
Do I even want to ventilate the roof, if there is a chance of asbestos being blown in, or should I just save my coppers to pay for a re-roof?
Any opinions will be gratefully received!
Thanks

 

[KenGMac]

Chriysotile is by far the least dangerous of the Asbestos family.

As for dust, by now the tiles will all have a pretty good "crust" on their outer surfaces which will tend to hold the small volume of Asbestos pretty much where it is, you will only get fibers escaping if you cut, sand, abrade or smash the tiles. Is there a layer of membrane on the inside of the roof below the tiles, or is there timber sarking fitted?

As for how dangerous this stuff is, read the attached?? OK it refers to Artex, but you have a broadly similar scenario???

https://www.cancerresearchuk.org/ab...stos-in-home-has-been-disturbed-not-realised?

Can you fit eaves vents? are there any fitted now??

Ridge vents may be a way to go?

Is there any actual air movement in the loft just now? remember all lofts get very, very warm / hot in summer sunshine.

Ken

 

[^woody^]

Why are you bothered about how hot the roof void gets? That's what happens to every house in summer

 

[RandomGrinch]

Thanks for the replies,
I wasn't really worried about the loft getting hot. The main issue is no air movement with the new firewalls. When the air was circulating through most of the terrace, the loft was relatively cool and there has never been condensation.
I'm concerned now, that the heat and lack of air movement is a warning of condensation to come.
Currently there is bitumen felt under the slates, a small gap in the soffit at the front and fascia tight against the wall at the back. So no through ventilation.
I can improve the soffit ventilation and was planning to use slate vents on the rear, but don't fancy disturbing the slates to do that now.
I'm also unsure of the risk of disturbance versuses the benefits of fitting a vented dry ridge.

 

[RandomGrinch]

Thanks for the link Ken, that's really interesting and a good antidote to the normal asbestos discussion on Google. I have dealt with asbestos in work and at home and have some familiarisation with dealing with it, so am less worried than some may be!

 

[^woody^]

Wedge open a few felt laps with polystyrene or a bit of timber, if you are worried - but there's no need to be .... no house with a underfelt built well into the 70's has roof ventilation ... and the roofs are still up - that's a few million.

 

[RandomGrinch]

Thanks Woody, I had tried opening the felt. The slates were very tight against it and again I couldn't feel any air movement. The thought of dust on top of the felt also put me off that approach.
So, the feeling is leave alone, there's probably not an issue! I will keep an eye out for condensation later in the year.
As my home was re-roofed with a grant in the eighties along with terrace after terrace, it makes you wonder how many people have asbestos cement fibre slates and don't realise.
Anyway, thanks for the advice, its appreciated.