How to fill the smallest of cracks with foam or silicone
I’m trying to fill some small spaces in between 2 x 6 roof decking that sits on top of finished timber frame rafters at the point above the exterior wall. The deck boards for the finished ceiling inside are the same ones that continue to the outside where they become the finished soffit boards.
These boards are not tongue and groove and were freshly milled when installed. They have since shrunk and left gaps of 1/16 of an inch to a 1/4 inch allowing for outside air to pass through the gaps and into the interior loft space.
I’m looking for a tool and/ or product that could fill these long narrow voids. Ideally the tip of the tool could reach into the full depth of the wall (18 inches with a 6″ wide rafter on either side), and fill the entirely space.
Does anyone know of a tool or an attachment for a spray foam gun or an attachment for a tube of silicone that would work, or should I just try and fabricate something and cross my fingers?
Hope my description is clear and thanks for any input.
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