A wall is several materials
Homeowners tend to think of a wall as drywall. A certified inspector sees layers: the gypsum board, the tape and joint compound at seams and screw heads, a skim coat or knockdown texture, and paint. In older homes there may be plaster over lath instead, with a finish coat on top. Each of these can be a separate material for sampling purposes.
Joint compound and some wall textures manufactured into the late 1970s could contain asbestos. Plaster in some older buildings did as well. When a wall is demolished, sawed or sanded, all of those layers become dust together. That is why kitchens, bathrooms and basement finishes in older metro Denver houses are common points where a remodel should pause for testing.
Wall-related materials and how remodels disturb them
| Material | Where you find it | Disturbed by |
|---|---|---|
| Joint compound | Seams, corners and fastener heads on drywall | Demolition, sanding, cutting openings for outlets or windows |
| Knockdown or orange-peel texture | Living areas and bedrooms of mid-century and 1970s homes | Patching, sanding, removal before a smooth finish |
| Plaster and finish coat | Older homes and apartment buildings with lath walls | Demolition, chasing in new wiring, opening walls for plumbing |
| Patch layers | Anywhere walls were repaired over decades | Any of the above; patches may differ from original material |
Order of work for a remodel that opens walls
- Map the walls to be opened.Mark every wall, ceiling and soffit that will be cut, removed or chased for new wiring and plumbing.
- Inspect what the work will touch.A CDPHE-certified building inspector samples the materials in those locations and documents results in a written report.
- Read the report with your contractor.Identify which materials are positive and how much of each will be disturbed.
- Separate abatement from remodeling.If removal is needed, schedule it with a certified abatement contractor before the general contractor's demolition starts.
- Wait for clearance.Only after the abated area passes clearance should carpenters, electricians and drywall installers begin.
Ask your remodeler before demolition day
- Which walls and ceilings will be removed or cut, and has each been sampled?
- Does your demolition crew know to stop if they uncover a material that was not in the report, such as old pipe wrap inside a chase?
- Who on this project holds CDPHE certification for asbestos work, if any abatement is required?
- Will the building department want to see the inspection report before issuing the remodel permit?
- How will dust from non-asbestos demolition be controlled once abatement is finished?
Common questions
My house was built in the late 1980s. Do I still need to test?
Newer homes are less likely to contain asbestos in wall materials, but Colorado's inspection requirements are tied to the work and the building, not only its age. Ask a certified inspector or check CDPHE guidance for your situation.
Can I take a sample of the drywall myself and mail it to a lab?
Cutting a sample is itself a small disturbance, and for regulated renovation work Colorado looks for inspection by certified personnel. A self-collected sample may not satisfy permit requirements.
General information for the Denver area, not a quote or professional advice. In an emergency, call 911.