Petrus Johannes van Genk was born in Bergen op Zoom (NB) in 1844 as the son of a furniture-maker. Like his brother C.P. van Genk had done before him he studied architecture in Antwerpen from 1864 until 1872. In 1873 he was in charge of the construction of the St. Lambertus in Etten, a neo-Gothic church designed by Belgian architect Bruggenaar. In 1875 Van Genk started a firm in Leur. In the diocese of Breda, which encompassed the western half of Noord-Brabant and the entire province of Zeeland, he quickly became the most important architect of catholic churches, of which he built ca. 20, but outside this diocese he had very few assignments. The style in which most of his churches were built was closely related to that of neo-Gothic churches in Belgium, based on early French Gothicism and with a prominent use of natural stone. Besides designing new churches he also restored several older ones.
The following is a list of Van Genk's profane and religious work. It is incomplete.

1877-1878 Den Hout (NB): church St. Cornelius

Three-aisled cruciform basilica in neo-Gothic style. Chapels added to the side-aisles in 1904.

1879 Bergen op Zoom (NB): house De Blauwen Hondt

House in neo-Baroque style. Built as a presbytery.

1881 Zundert (NB): restoration church St. Trudo

Restoration of a medieval church, with drastic changes to the interior. Church demolished in 1925.

1882 Oosterhout (NB): church H. Hart

Church in neo-Gothic style. Demolished in 1974 except for the front.

1884 De Heen (NB): church H. Maria Hemelvaart

One-aisled church in neo-Gothic style. Drastically extended in 1951.

1885-1886 Zuiddorpe (Z): church O.L. Vrouwe ten Hemelopneming

Three-aisled cruciform basilica in neo-Gothic style. Tower next to the front.

1885-1886 Culemborg (G): church St. Barbara

Three-aisled cruciform basilica in neo-Gothic style. Tower next to the front.

1888-1889 Leur (NB): church St. Petrus

Three-aisled cruciform church in neo-Gothic style. Front with two towers.

1889-1890 Klundert (NB): church St. Johannes de Doper

Three-aisled cruciform church in neo-Gothic style. Badly damaged in 1944. Tower not rebuilt but replaced by a neo-Romanesque facade in 1946-1947.

Ca. 1890 Hulst (Z): restoration church St. Willibrordus

Repairs to the transept and choir, started by architect P. Soffers.

1892-1893 Hengstdijk (Z): church St. Catharina

One-aisled cruciform church in neo-Gothic style.

1892-1893 Breda (NB): chapel Elisabeth Gasthuis

Chapel for a hospital.

1894-1895 Yerseke (Z): church St. Anna

One-aisled church in neo-Romanesque style.

1895 Riel (NB): church St. Antonius Abt

Cruciform church in neo-Gothic style. Transept added by J.H.H. van Groenendael in 1935.

1897 Ossendrecht (NB): church St. Gertrudis

Cruciform basilica in neo-Gothic style.

1897 Sas van Gent (Z): Franciscan convent

Convent with school.

1897-1898 Breda: facade Elisabeth Gasthuis

New facade for a hospital.

1900 Breda (NB): church H. Hart

Three-aisled cruciform basilica in neo-Gothic style. Transept and choir built in 1930-1931.

1901-1902 Kwadendamme (Z): church St. Bonifatius

One-aisled cruciform church in neo-Gothic style.

1903-1904 Wagenberg (NB): church St. Gummarus

Big three-aisled cruciform basilica in neo-Gothic style.