Chapter 34 Key Takeaways: Hazardous Materials — Lead, Asbestos, Radon, and Mold

The Four Hazards at a Glance

Lead Paint: Critical Points

• 1978 is the date. Pre-1978 construction should be assumed to contain lead paint until tested.
• Intact paint = low risk. The danger is dust from mechanical disturbance — sanding, scraping, cutting.
• Never dry-sand unknown paint in a pre-1978 home without testing first.
• RRP Rule: Contractors disturbing lead paint in pre-1978 homes with children under six or pregnant women must be EPA-certified and follow lead-safe work practices.
• Professional testing: XRF ($300–$600 for a home inspection) or paint chip sampling ($25–$50/sample + lab).

Asbestos: Critical Points

• The rule: If it ain't broke, don't break it. Intact asbestos-containing material poses minimal immediate risk.
• Disturbing ACM releases fibers — sanding, cutting, drilling, breaking, demolishing.
• Common locations: 9" and 12" floor tiles, pipe insulation, popcorn ceilings, textured wall compound, cement board siding and roofing (homes from 1920s–1970s).
• Friable > Non-friable risk. Deteriorated pipe insulation can release fibers by touch; intact floor tiles require mechanical force.
• Professional abatement required for friable ACM and large areas of non-friable ACM. Testing (inspector) and abatement should be separate companies.

Radon: Critical Points

⚠️ This is not optional: Any home with a basement or crawlspace should be tested.

• $15 short-term test from hardware stores or sosradon.org
• Action level: 4 pCi/L. If your result is at or above this, mitigate.
• Sub-slab depressurization is the primary mitigation method — costs $800–$2,500 professionally installed.
• Mitigation reduces radon 80–99%.
• EPA radon zone map shows county-level risk, but testing is required regardless of zone.
• Post-mitigation testing confirms effectiveness — always do it.

Mold: Critical Points

• Mold = moisture problem. Fix the moisture source or remediation will fail.
• Bleach does not remediate porous materials — it kills surface mold but doesn't eliminate hyphae in the material.
• Remove contaminated porous materials (drywall, insulation, carpet) rather than cleaning them.
• Over 10 square feet of mold generally warrants professional remediation.
• Independent clearance testing by an industrial hygienist after remediation confirms success.

Disclosure Requirements

• Federal: Sellers of pre-1978 homes must disclose known lead hazards and provide the EPA pamphlet. Buyers get 10-day inspection period.
• State: Most states require disclosure of all known material defects, including asbestos, radon, mold, and water intrusion.
• "Known" is interpreted broadly. Remediated issues, historical inspections, and prior test results all need to be disclosed.

Key Cost Benchmarks

One-Sentence Takeaway

The hazardous materials in older homes are manageable — test to know what you have, leave intact materials alone, call certified professionals when disturbance is required, and disclose what you know when you sell.