Background: We had an L shaped extension put onto our house (back and side) by previous occupiers. We want to knock through a door way through the old external wall and into the new extension. I've had a look at a few sites and the process seems relatively simple for a straight forward wall. http://www.houseprofessionals.com/diy/brickwork/opening_a_wall.htm However the door way we want to knock through is underneath our stairs so the only access to fit 2 lintels is from the other side (from the extension) working towards the house.
Problem: If I use 2 acrows with strong boys, how do the strong boys fit right through the cavity to reach the inner line of bricks considering the strong boys are only 150mm in depth yet the double skinned wall is 310mm?
Another problem is because I have to work from the extension in towards the house and don't have access the other way, how could I possibly fit the lintels if the acrows / strong boys are hard against the wall?
Even if the builder does turn up I'd be really curious to know how it is done.
Any advice would be great.