My basement runs at about 55-60 F

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The above light box set up runs at about 75F at the floor and about 100F at the top. I have nails in the walls to hang the planted cups at a height needed to get the best temperature for germination. In your own house you can place a shelf at 6 feet and the light fixture on the joist. This could be 10F or more from the floor. In my experience the higher the temperature the quicker the sprout. up to 105F

I'd say do the heat mat with a ventilated covering on until the first true leaves appear and then remove WHILE using a heat mat thermostat.

You can get one on amazon for about 30$ - and check your seed packages or an online resource for germination temperatures on seeds, some actually prefer to be cool

...but it's important to realize soil temperature is 'usually' lower than air temperature, hence the importance of using a heat mat thermostat.

This is a good example from cultivators corner on min, best, and max temps and the effects of temp on seedlings.