1. The room measures 2.4m side to side: the two RSJs (2.7m each) will span the proposed opening into the extension, to make a larger room. The RSJs will not be supported by brick piers - the extension walls are built flush with the existing walls.
2. At one end, the RSJs will be perpendicular to the existing (external) cavity walls. At the other, they will be in line with the existing, external cavity walls.
3. Because the extension has enclosed part of the existing, external cavity walls, the lintels will, in effect, sit on what are now internal cavity walls. Can the ends of both lintels (bolted together?) - share a padstone at either end?
2. we want the lintels to be concealed, i.e. to sit flush with the ceiling. How difficult is this to do? Thank you. (UK email address provided)
