The origins of the church lie in a burial ground laid out in 1911 at Söromsjön, in the southernmost part of Venjans parish. A chapel was planned soon after, with foundations laid in 1919, but building work stalled for two decades. The chapel was finally completed in 1938–1939 to designs credited to architect Edward Dahlbäck (also recorded as Dahlberg), with Viking Göransson also named in one source.
The building is a simple whitewashed brick structure on a cast concrete foundation, comprising a rectangular nave, a narrower and lower chancel to the east, a porch to the west, and a sacristy attached to the nave's south side. Its steep roofs are covered in black slate. A cement cross tops the chancel gable, while a sandstone tablet above the west entrance records the church's completion date and the reigning monarch and bishop of the time.
Inside, the nave has a barrel-vaulted ceiling, while the chancel is covered by a brick cross-vault, the two spaces linked by a semicircular triumphal arch. The altar wall is decorated with a fresco painted in 1939 by Erik Alm, described in one source as a fresco and in another as a lime-based wall painting; either way, it remains the church's most distinctive feature. Most of the fittings date from the same period as the building itself.
Among the older furnishings is a neo-Gothic altar cross from 1872, originally made for Balingsta new church; when that church was demolished in 1934, the cross was given to Siknäs. The octagonal pulpit stands on a tall, whitewashed masonry base and is crowned by a canopy topped with a gilded cross on an orb. The red limestone font, designed by the Libraria workshop, was acquired in 1945.
A freestanding bell tower, built in 1925 and covered with a copper-clad roof, stands to the south of the church. The organ, built in 1939 by John Vesterlunds Orgelbyggeri, is a pneumatic instrument typical of small Swedish parish churches of its era.