Winter Shop & Garage Safety: Heaters, CO & Clearances | Danner
Winter Safety in Shops & Garages: Heaters, CO, and Clearances
Nebraska winters make shops and garages work overtime. Heat is great—until safety slips. This guide covers safe heater choices, carbon-monoxide basics, required clearances, and one upgrade that helps every heater work easier: closed-cell spray foam on the walls and roof deck.
Pick the Right Heater for the Space
- Sealed-combustion heaters draw air from outdoors and exhaust outside—safer around dust, fumes, and stored fuels.
- Vented units (properly installed) reduce moisture and CO risk compared to unvented space heaters.
- Electric options avoid combustion altogether but still need clearances and proper wiring.
Tip: Match heater output (BTUs/Watts) to the space after insulation upgrades. A tighter envelope can mean a smaller, safer unit.
Carbon Monoxide: Detectors & Placement
- Install UL-listed CO detectors at breathing height (often 4–5 ft) and near sleeping areas if attached to a home.
- Test monthly; replace batteries on a schedule.
- If an alarm sounds, evacuate and ventilate; have equipment inspected.
Clearances & Combustibles
- Respect the heater’s listed clearances to walls, ceilings, vehicles, racking, and stored materials.
- Keep oily rags, solvents, and sawdust away from heat sources.
- Don’t block return air or exhaust paths.
Why Spray Foam Helps Safety (and Comfort)
Uninsulated metal or concrete gets cold fast, forcing heaters to run harder and longer. Closed-cell spray foam adds a thermal break and air seal so surfaces stay warmer—reducing run time, cycling, and hot-spot risks. It also helps control condensation, which protects tools and materials.
Good targets: Roof underside, wall-to-roof transitions, and known cold/drafty spots. Many shops start there and add walls later if they plan to heat regularly.
Quick Winter Checklist
- Test CO detectors and change batteries.
- Vacuum dust from heater intakes and keep exhausts clear.
- Verify listed clearances; move stacked items as needed.
- Squeegee floor puddles to lower indoor humidity.
- Seal obvious door leaks; consider closed-cell foam in problem areas.
FAQ
Can I use an unvented heater?
Check local codes. Even when allowed, unvented units add moisture and CO risk; sealed-combustion or properly vented is often safer.
- Do I need to foam the whole shop?
Not always. Start with the roof underside and eaves/joins—often the biggest win for safety and comfort.





