How do you say quay house in Welsh?

There isn't a direct, single-word translation for "quay house" in Welsh. You would have to use a more descriptive phrase. Here are some options:

Literal translation:

* Tŷ ar y cae: This literally translates to "house on the quay," but might sound a bit awkward.

More natural expressions:

* Tŷ ger y cwch: This translates to "house near the boat," which is a more natural way to describe a house by the quay.

* Tŷ ger y lanfa: This translates to "house near the wharf," which is another way to describe a house by the quay.

* Tŷ ar lan y môr ger y cae: This translates to "house on the seashore near the quay," which is a more specific description and captures the location more accurately.

Ultimately, the best way to say "quay house" in Welsh will depend on the specific context and what you want to emphasize.