To secure open floor vents and prevent mice or insects from entering, you have a few practical options. First, consider installing vent covers or grilles specifically designed to keep pests out. These can be found at home improvement stores and typically range from $10 to $50 per cover, depending on size and material.
Another option is to use magnetic vent covers, which are easy to install and can be removed when needed. These often cost between $5 and $20 per cover. If you prefer a more permanent solution, you could hire a professional to install sealed vent covers or even ductwork modifications to ensure that pests cannot access the vents.
Before you proceed, it’s wise to assess the entire area for any existing gaps or holes that might allow pests to enter, and seal those with appropriate materials like caulk or foam insulation.
For the best results and to ensure compliance with local building codes, consider consulting with a licensed HVAC professional. They can provide tailored solutions based on your specific situation.
As a next step, I recommend getting 2–3 local quotes on Handyman.com for vent covers or professional installation services.
— Assisted answer