The transition to a more sustainable Aluminum industry will require an increased use of Al scrap in future Al products. In this work we investigate the effect on microstructure, properties and castability of foundry alloy AlSi10MnMg formulated with Al recovered from incinerator bottom ash (IBA Al). IBA Al is found to have low levels of Si (~1wt%), Mn, Mg and Cu, and could therefore be a potential source material for Al-Si foundry alloys. AlSi10MnMg was formulated by melting pre-alloyed IBA mixed with pure Al together with material from the pure target alloy. Different levels of IBA Al within the formulated alloy were studied, 10%, 20%, 30% and 40%, to address the effect of added scrap material. The effect of cooling rate was studied by comparing sand mold castings with metal mold castings. Microstructures of the cast alloys were investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) in combination with thermodynamic modelling. Additionally, quantitative analysis of the intermetallic particles was done by the butanol method. Hot tearing tests and compression tests were performed as initial benchmarking of the effect of Al scrap on castability and properties. This work contributes to build fundamental understanding of the effects of impurities contained in IBA Al on properties and castability of Al-Si foundry alloys, which is a critical step towards a more sustainable Al industry.