Hi,

What are your project settings in Visual studio? In the build options you can set the startuppage not to be built as well as the setting for building web site as a part of the solution - this can improve the building time. However, if you are running the site from the Visual Studio server - the performance is not that good since it was made mainly for debugging. To check smaller changes is better to use IIS server.

Best regards,
Juraj Ondrus