What is an antonym of thatch?

There isn't one perfect antonym for "thatch" as it depends on the context. Here are a few options depending on what you're trying to convey:

If "thatch" refers to the material:

* Tile: For roofing, a tile roof would be the opposite of a thatched roof.

* Shingle: Another common roofing material.

* Slate: A more durable and less common roofing material.

* Metal: A very different material for roofing.

If "thatch" refers to the act of covering with thatch:

* Tile: To tile a roof instead of thatching it.

* Shingle: To shingle a roof instead of thatching it.

* Slate: To slate a roof instead of thatching it.

* Metal: To metal a roof instead of thatching it.

If "thatch" refers to the way something is covered:

* Smooth: A smooth surface is the opposite of a thatched surface.

* Bare: A bare surface is the opposite of a thatched surface.

* Modern: A modern building material would be the opposite of thatch.

The best antonym depends on what you're trying to communicate.