Most Chicago houses built before the 1950s have plaster walls, and most built since have drywall. The difference matters the moment a remodel starts, because plaster is thicker, heavier and messier to remove, and the trim around your doors and windows was fitted to it.
How do I tell which one I have?
- Knock on the wall. Drywall sounds hollow between the studs. Plaster sounds dull and solid everywhere.
- Push a thumbtack in. It goes into drywall. Plaster sends it back bent.
- Look where nobody finished the job, such as the basement ceiling or the attic stairs. Thin wood strips with hardened plaster squeezed between them are lath.
- Check the age of the house. Built before 1950, it is probably plaster.
What is the difference?
| Plaster on lath | Drywall | |
|---|---|---|
| Thickness | About 7/8 inch with the lath | 1/2 inch is standard |
| Weight | Heavy | Light |
| Sound | Blocks more | Blocks less |
| Repair | Slower, and takes skill | Quick, and widely done |
| Removal | Comes down as rubble and dust | Comes down in pieces |
Should the plaster stay or go?
Keep it when it is flat, firm and cracked only at the surface. Hairline cracks can be patched. Replace it when it has pulled away from the lath, which you can feel as a patch that gives when you press it, or when the wall has to be opened anyway for wiring or plumbing.
There is a third option: leave sound plaster in place and hang thin drywall over it. That keeps the dust inside the wall, at the cost of a slightly thicker one.
What changes when plaster comes out?
- The wall gets thinner. New half-inch drywall is thinner than the plaster it replaces, so door and window trim no longer sits flush unless the studs are built out or thicker board is used.
- There is a lot of dust. Taking down plaster is among the dirtiest jobs in a house. Ask how the room will be sealed off.
- Old paint gets disturbed. Paint in houses built before 1978 can contain lead, and federal rules call for lead-safe work methods when it is broken up. Ask how that will be handled.
- The wall shows what is in it. Old wiring and plumbing come into view and have to be dealt with before the wall is closed.
For how the rest of the job runs once the walls are open, see home remodeling in Chicago. To talk through your walls, call (773) 676-3830.