01 — Why 1978 is the line that matters
Lead-based residential paint was banned that year, not before
The EPA's Renovation, Repair and Painting Rule treats any home or child-occupied facility built before 1978 as likely to contain lead-based paint on window sashes, trim, and the glazing putty that holds the glass in place. Window components specifically are called out in the rule because glazing work, by its nature, disturbs painted surfaces directly.
This is not a rule that only applies to paid contractors. While the RRP Rule's certification and training requirements are aimed at people being paid to do the work, EPA's own guidance for do-it-yourself renovators is explicit that homeowners doing this work themselves should still use lead-safe work practices, because the health risk to the people living in the house does not change based on who is holding the scraper.
The safest working assumption, absent a test, is that a pre-1978 window's paint and putty contain lead. Newer windows installed later into an older home are the exception worth checking separately, since a window replaced in the last few decades may carry only lead-free paint even in an otherwise pre-1978 house.
Lead exposure from disturbed paint remains the largest single cause of childhood lead poisoning in the United States, which is why the rule focuses so specifically on the moment paint gets scraped, sanded, or heat-stripped rather than on the paint sitting undisturbed. A window that has been painted over repeatedly without disturbance for decades is a lower everyday risk than the same window mid-repair.
02 — Testing before you scrape
A test kit costs a few dollars and removes the guesswork
EPA recognizes specific lead test kits that a homeowner can use directly on painted window components before starting work. A reliable negative result on an EPA-recognized kit means the RRP Rule's lead-safe practices are not required for that specific surface, which can save meaningful time and effort on a window that turns out to be lead-free.
A positive result, or no test at all, means proceeding as though lead is present. Keeping a record of any test result is useful even for a homeowner working alone, since it answers the question definitively if the same window needs attention again later, rather than requiring a second guess.
Old glazing putty is a reasonable focus for testing precisely because it sits directly against the glass, gets scraped rather than sanded in most repair methods, and was, in many older homes, applied with a linseed oil putty compound that used lead-based pigments and driers as a matter of common practice at the time.
Test more than one spot on the same window if the frame shows different paint colors or an obvious repaint layer, since a single sash can carry several decades of paint applied at different times, only some of which may contain lead. A negative result on the top color does not guarantee the same result on a layer underneath.
03 — Containing the dust
The goal is keeping dust in one place, not eliminating every particle
EPA's DIY lead-safe practices center on containment. Covering the immediate work area with plastic sheeting before starting, closing off the room from the rest of the house, and keeping children and pets out of the work area for the duration are the basic setup steps, done before the first scrape of putty comes off the glass.
Wetting the putty lightly before scraping, rather than working it dry, reduces how much fine dust becomes airborne in the first place, the same underlying principle behind wet-cutting masonry. A heat gun set below the temperature that vaporizes lead, or a chemical stripper used according to its label, are both lower-dust alternatives to aggressive dry scraping or power sanding, which EPA specifically discourages for lead-painted surfaces.
A HEPA-filtered vacuum, not a standard shop vacuum, is the right tool for cleanup, because a standard vacuum can pass fine lead dust straight through its filter and back into the air. Cleaning the work area at the end of every session, not just at the end of the whole project, keeps dust from accumulating and spreading beyond the covered zone.
04 — Who this rule actually applies to
Renters and landlords face a different set of obligations than owner-occupants
A homeowner working on their own pre-1978 house they live in, without paying anyone, generally falls outside the RRP Rule's formal certification requirement, though EPA still recommends following the same lead-safe practices for the household's own protection. The calculation changes the moment the property is rented out.
A landlord or property manager performing paint-disturbing work, including window glazing, on a rented pre-1978 unit is treated the same as a paid contractor under the RRP Rule and is expected to follow certified lead-safe work practices, because the rule is built around protecting occupants who did not choose the home's paint history and may include children.
Anyone unsure which category applies to their situation, particularly a landlord doing work themselves rather than hiring it out, can check EPA's lead program pages directly rather than assuming the homeowner exemption applies by default.
Hiring out the work does not remove the need to check credentials. A contractor working on a pre-1978 home should be able to show proof of RRP certification before starting, and asking to see it is a reasonable, ordinary step, not an imposition on a legitimate lead-safe certified firm.
Quick reference
- Assume lead-based paint and putty on any window in a home built before 1978, unless tested otherwise
- Use an EPA-recognized test kit on the putty and paint before scraping
- Cover the work area with plastic sheeting and keep children and pets out while working
- Wet the putty before scraping and avoid dry sanding or open-flame torches
- Clean up with a HEPA-filtered vacuum, not a standard shop vacuum
- Landlords doing this work on a rented pre-1978 unit face RRP Rule obligations even without hiring a contractor
Caution
Lead dust is dangerous in amounts too small to see, and children are especially vulnerable to its effects. Do not dry sand or use an open flame to remove old paint or putty suspected of containing lead, and keep children and pregnant household members out of the work area until cleanup is complete.
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