The bank is offering a range of products with interest rates based on the size of the deposit that the buyer is bringing to the transaction.
It is also offering a new product to Irish people living overseas who wish to invest in property in Ireland.
PTSB Head of Mortgages Ger Mitchell said investors were looking for a very different type of property to the type being sought by those looking to purchase a family home.
Speaking on RTÉ's Morning Ireland, he said: "Investors are already active in the market.
"There's a very healthy rental market with 470,000 people in rental accommodation at the moment. Investors are typically looking at purchasing apartments or duplexes".
He acknowledged that there would be a cohort of overseas buyers who would look to purchase family homes with a view to coming back to live in Ireland.
"This has been a significant problem for people who bought at the top of the market, but there has been a considerable correction in house prices.
"There are a lot of suitable properties for investment available at a suitable price," Mr Mitchell said.