We have been building this mud brick studio for over a year now. This weekends project was framing up some double glazed stain glass window panels and installing them. We used F17 hardwood for the frames and screwed them together with galvanised screws and then screwed them to the building framing with baton screws. Flashing on top to make water proof. So all fairly strong. Now to lay more mud brick up underneath to finally finish the walls.