What should I report before anyone looks at it?
Don't touch, operate, measure or try to secure the broken glass yourself. Describe the room, the floor level, the visible damage and when you noticed it, and share existing paperwork or photos only if you can do that without going near the damage. Ask whether professional temporary protection is needed. Broken glass can cause serious cuts; the Consumer Product Safety Commission's tempered glass safety alert describes safety-glazing standards meant to reduce cutting and piercing injuries when glass breaks.
Is this a single pane or an insulated glass unit?
Some windows use insulated glass units: two or more panes with an insulating air or gas space between them, sometimes with a low-E coating. The Building America Solution Center's window sash replacement guide describes both. That's why “clear glass” alone isn't a complete description of what needs replacing.
Ask the professional to record the glazing type, dimensions, thickness, coatings, tint and other relevant specifications. If one layer of a multipane window is broken, ask whether the proposal replaces the whole sealed unit and how its performance will compare with the original. The Department of Energy's window glass replacement job aid calls for replacement glass that matches the original in color and look and meets or exceeds the specifications of the previous glazing. Leave measuring and close inspection to the professional.
Why replace the glass, the sash or the entire window?
Ask for the reason behind the proposed scope. According to the window sash replacement guide, replacing the sash keeps the existing frame and can make sense when the existing sashes can't accommodate new insulated glass units or are in poor condition, but the frame's condition and geometry can be a factor.
Ask for a written distinction between the damaged glass and any separately identified sash or frame defect. A useful question is: “What condition prevents a smaller repair?” Keep unrelated upgrades separate so you can see what's needed to restore the broken glazing.
Does this opening require safety glazing?
Ask the installer to verify the safety-glazing requirements for that exact opening under the local code, and don't assume copying the existing glass is enough. DOE's glass replacement job aid calls for tempered glass where code requires it, and DOE's window replacement checklist says safety glass should be specified in accordance with local codes.
Code and permit questions depend on where the house is. In Bristol, our guide on which Bristol permit office to contact explains that Bristol Borough and Bristol Township have separate offices. For a Philadelphia home, our guide to looking up a home's permit history shows how to see what work has been recorded before.
Was the home built before 1978?
If so, DOE's glass replacement job aid and window replacement checklist say to assume lead-based paint is present unless testing shows otherwise, and the checklist says window replacement work in pre-1978 homes should comply with EPA's Lead Renovation, Repair and Painting Rule. Ask whether the work will disturb painted surfaces and how lead-safe practices will be followed.
What does the manufacturer allow?
If the manufacturer and model can be identified from existing records or a professional inspection, ask the professional to confirm that the proposed glass or sash and the installation method follow the manufacturer's instructions. DOE's window replacement checklist calls for installing replacement windows according to the manufacturer's specifications.
Before authorizing an order, ask: Is a compatible replacement available? Does the manufacturer permit glass-only replacement for this model? Is approval needed before work begins? What, if anything, is covered for glass, labor or related parts? Get the answers in writing rather than assuming a general warranty applies to your window.
What should the written scope and final records include?
Ask for the replacement assembly and glass specification in writing, plus who handles temporary protection, removal of the broken glass, cleanup, disposal and any extra parts. Ask how the fit and the finished installation will be checked; the glass replacement job aid stresses sizing the new glass correctly for the opening and sealing it to prevent air and water leakage.
Keep the approved scope, product identification, invoice and written warranty terms together, as covered in our guide to documents to keep after a home repair. If the breakage involved a suspected product-safety problem or an injury, the CPSC alert asks consumers to report safety-related glass incidents at SaferProducts.gov.