Preheat the oven to 350°F (175°C).
In a medium bowl, whisk together the all-purpose flour, baking soda, and salt. Set aside.
In a large bowl, beat the softened unsalted butter, granulated sugar, and brown sugar with an electric mixer until creamy and smooth, about 2 minutes.
Add the vanilla extract and eggs one at a time, beating well after each addition.
Gradually add the flour mixture to the butter mixture, mixing on low speed until combined.
Stir in the semisweet chocolate chips evenly.
Divide the dough into two portions and roll each between two sheets of parchment paper to about 1/4 inch thickness.
Using a printed template or freehand, cut out the shapes needed for the house walls and roof (typically 2 rectangles for walls, 2 rectangles for roof, 2 smaller rectangles or squares for front and back).
Place the cookie shapes on parchment-lined baking sheets about 1 inch apart.
Bake in the preheated oven for 12 to 15 minutes or until the edges are golden brown.
Remove from oven and let cool completely on wire racks.
While cookies cool, prepare the royal icing by combining the powdered sugar, meringue powder, and warm water in a large bowl.
Beat on high speed with an electric mixer until stiff peaks form, about 5 to 7 minutes.
Transfer the royal icing to a piping bag or a resealable plastic bag with a small corner cut off.
Assemble the house by piping royal icing along the edges of the cookie pieces and pressing them together to form walls and roof.
Hold pieces in place for a few minutes to set, then allow the assembled house to dry and harden for at least 2 hours before decorating or displaying.