Background/Objectives: In 2023, a pilot study of an adapted Smoke-Free Home (SFH) Program was conducted in Barcelona, Spain. Two weeks after the intervention delivery, 68% of households attempted to create an SFH, and 17% successfully adopted one. This study aimed to (1) identify the barriers and facilitators to the voluntary adoption of an SFH, (2) explore gender roles and household dynamics in the adoption process and (3) identify the perceived utility of the program materials.

Methods: In 2024-2025 we conducted one triangular discussion group and five individual semi-structured interviews with eight pilot participants. The interview protocol was structured in four sections: (1) overall experience with the project); (2) motivations, barriers, and facilitators in SFH adoption; (3) family dynamics and communication, and); (4) SFH maintenance. All participants received an information sheet and signed an informed consent form. The interviews were recorded, transcribed, and analysed using thematic analysis.

Results: The main barriers to SFH adoption included lack of control over tobacco use and limited persuasive capacity among non-smoking participants. For smoking participants, key challenges included nicotine dependence, stress, and restrictions on smoking in outdoor home areas (e.g., balconies). Facilitators of SFH adoption included increased knowledge about the harms of second-hand third-hand smoke exposure, smokers' motivation to quit, and support from all family members. The importance of reaching a consensus and avoiding conflict when establishing an SFH was emphasized. Women played a crucial role as guardians of family health and well-being, often initiating and promoting SFH adoption within households. The intervention materials were considered useful in raising awareness about exposure, particularly regarding the impact of smoking in outdoor areas and third-hand smoke. However, smokers’ intrinsic motivation to quit appears to be a more significant factor in achieving SFH adoption.

Conclusions/Recommendations: This qualitative research provided an in-depth exploration of the barriers and facilitators to the voluntary adoption of SFH among pilot participants. The intervention materials were useful and increased participants’ awareness of the harms of smoking at home. However, smoker’s motivation to quit emerged as the most decisive factor in successful SFH adoption. Future interventions should incorporate strategies to enhance smokers' commitment to quitting while supporting household-wide efforts to establish SFHs.

Funding: Instituto de Salud Carlos III through the project PI21/00818 (Co-funded by European Regional Development Fund. ERDF, a way to build Europe). European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie (grant No 101008139). 2021 SGR 00906-AGAUR 2022.