Ventiliation - Open Eaves vs Closed Eaves

[Wood4daTrees]

Hi there,

I am currently considering a complete re-roof of my home, a detached 1930's house with a slate pitched roof no felt/membrane with open eaves, 5"-6" timber attached to the top of the exposed rafters under the last row of slates.

My intention is to add plenty of loft insulation to save on energy bills but my concern is the ventilation and health of the roof.
I have done lots of reading of related topic threads but still do not have an absolute clear answer.

So to allow moisture/humidity to escape I am thinking of going for dry ridge system plus breathable membrane.

Confused; as it is open eaves, how do I get fresh air into the roof. Here are my queries :-

Can I add fascia plus soffits ?
Pros : Able to add over-fascia ventilation

Good fixing for guttering as the rafter-ends are poor from previous gutter fixings.​

Cons: Will hide half the soldier brickwork above the windows.

Unsure if it will cause other problems ?​

Can I just add fascia, no soffits ?
Pros : Able to over-fascia vents

Good fixing for guttering
Will impede the soldier brickwork less​

Cons: ?

Can I drill and fix circular soffit vents into current above-rafter timber ?
Pros : Ventilation ?
Cons: Possible difficulty in drilling and fixing circular vents

Still have poor gutter-fixing
?​

Sorry for the long post but I wanted to provide as much information.
Thanks for any help and advice.

 

[datarebal]

I'm guessing you have the rafter feet showing with a say 6 x 1 / 150 x 25 flat timber fix top side of rafter?
if so cutting holes for circular soffit vents will not vent anything.
you can vent by using a vent strip between the edge of this board and brick you might need t trim the board and or brick.
fixing gutters, side rafter brackets...

 

[Wood4daTrees]

Databal, yes correct about the flat timber. Also yes, I can see that soffit vents won't vent anything now that you mention it.

Trimming the timber or brick seems to be too much of a mission.

I am thinking of just adding a black fascia plus over-fascia vents no soffits.

Do think it would look ok or a pigs-ear ?

Many thanks.

 

[datarebal]

Shame it sounds a mission, it would help keep the original look.
Fascia and over fascia vents could work if you make sure the airflow has a clear passage . Are you removing the flat timber ?

 

[Wood4daTrees]

Fascia + over-fascia vents finished height would be just above the timber. Then rafter roll and eaves tray.
No, not considering removing the timber as this encloses the loft space from birds, etc. So is effectively the soffit at a different height.

Any benefit by removing the timber ?

 

[Wood4daTrees]

Thank you for your question. It has got the 'old-noggin' ticking.
I have now realised that the eaves tray will be laying flat on the 6"x1" timber so even with over-fascia vents and the rafter roll the air flow will be blocked.

I am thinking that maybe I will have to install something like another set of over-fascia vents under the rear of the eaves tray, raising it off the timber and so creating the air flow passage.


What are your thought please ?

 

[datarebal]

counter batten over the timber

 

[bobsuerita]

http://www.keymer.co.uk/wp-content/themes/keymer/docs/Keymer_2015_2016.pdf

scroll through here to give you a few ideas
also vent detail if you have noggings between rafter

 

[Wood4daTrees]

Datarebal : Thats nice and simple, thank you.

 

[Wood4daTrees]

bobsuerita, thanks I've scrolled through Keymer.pdf and I am still digesting it.

Regarding the noggin vent.jpg not sure how this can be applied with my open eaves roof.
Which is brick, rafters coming through, brick between rafters, 6" x 1" timber on top of the rafters capping the brick.

I would upload a picture but I am not sure how to do this yet.