Cold roof space soffit/wall junction

[WWilts]

New build in progress.

 

Roof covering: Roofshield air permeable membrane with Cambrian slate on top.
Soffits well pinned down to outer leaf by wood/screws. Eaves have PIR insulation against inner leaf, crown wool insulation to spill out from loft into remaining eaves space.

 

Is there any real reason to be siliconing the soffit/wall junction? (red arrow)

[nod]

No there isn’t 

Other than Aesthetics 

 

[Simplysimon]

what are you doing for ventilation?

 

[WWilts]

No need for ventilation with this air permeable roof membrane

[saveasteading]

On 03/04/2022 at 13:05, WWilts said:

any real reason to be siliconing the soffit/wall junction?

If there is a gap, then insects will enter and live in the eaves. Bees and wasps mine into  PIR. 

Whether that is good or bad is another discussion.

[WWilts]

1 hour ago, saveasteading said:

If there is a gap, then insects will enter and live in the eaves.

Would a plastic soffit vent mesh do the job? (folded and inserted into the tiny gap)
Or is multipurpose silicone better?

[saveasteading]

For a few mm just silicone. A named one as it needs to be stand a lot of weather and uv, and you dont want to be doing that again.

[Simplysimon]

On 03/04/2022 at 16:57, WWilts said:

No need for ventilation with this air permeable roof membrane

forgot you don't board roofs down there