Put the decision into the scope
Include the window opening as a distinct detail in a tub-to-shower scope. Specify treatment of the sill, jambs and waterproofing connection, and assess the window itself for the changed exposure. Assign any replacement or alteration to a named work package instead of leaving it outside the shower installer's boundary.
Before accepting a proposal
Check that the written proposal names the products, defines the demolition boundary and explains the connection to retained work. Identify any allowance or unresolved selection, and ask who coordinates the relevant trades. Agree how concealed conditions will be documented and how changes require authorization. A broad installation label leaves too much room for different assumptions about what the finished project includes.
What should the window detail resolve?
How water drains away from the opening and how the shower waterproofing connects around it. A general instruction to seal the edges does not describe the whole assembly or establish that the window is suitable.
The owner should confirm the proposed service scope and provider availability independently. This guidance does not identify an approved contractor, establish coverage for a specific property or guarantee acceptance of the project.
The written scope is the reference.Use the provider’s proposal to record the accepted work, products, responsibilities and exclusions. Website examples do not establish an installation specification for your home.