This foundation is a little tricky because some parts go flush along the edge of the base and others will intersect across it. Put all the parts in numerical order. Start with number 13, then 1 and continue until you get to 12. Notice that number 6 intersects. Use a lot of glue because you won't be able to go back and add additional glue to the joints. The area between the floor and base will be too narrow for access.
The kitchen porch steps are very confusing because they show no pictures of it. Basically you make a box around the step opening in Foundation 13 with the square step pieces. Then you take the side piece that’s shaped like an L and laminate it against one of the squares so it faces in the same direction as the L shaped end of Foundation 8.
When you reach Foundation 12, you basically have already gone around the base. Number 14 begins the intersecting middle pieces. Put them in order or they won't fit properly since some interlock with each other.
Check your base several times and make sure that all joints are square and tight but don’t let the glue dry before you add your floor. You need the base and foundations to still have movement so you can position the first floor correctly. Your base may appear wobbly or shaky. This can happen because of slight warping but don’t worry about it. Just make sure that all tabs and slots are fitting tightly and all joints are flush. When you add the floor on top of this structure, it will make it sturdy and flat.
To add the floor you will probably need a hammer or mallet to help you get tabs into slots. It's hard to tell just where to put glue but put it on all exposed edges and you will be able to go back over the joints with more glue later. Hammer your floor in and make sure that the two pieces butt tightly against each other. Use masking tape to hold it tightly against the base. Make sure there’s no gaps.
Turn the structure over, the masking tape won't let it fall apart and glue on the gussets. Make sure you use wood glue for this. Once the gussets are in place, you can go over all the joints on the bottom of the base with wood glue. It’s a very tight and narrow area between the foundation and floor but use your finger and spread glue into those joints. You won't be able to do the same for the foundation and base, top part, that’s why I said to use a lot of glue since you can't go over it again.
Make sure you cover all joints. Be messy, no one is going to see this part since it's under the dollhouse. Add extra glue to all slots with tabs and to the joints between the two butted pieces of the base.
Keep the floor clamped to the base overnight and let everything dry.
