Hi , It never ceases to amaze me how some of use leave our van which is only a tin box overnight in weather up to 7-8 below freezing and think we can work the next day !My work means I start 5 am for 4 days and if I miss days due to weather I will not make up the time ,so this is what I do and in years have not lost work
1. Leave fan heater in van on a timer coming on for 15 mins every hour from 11 pm on
2. Use a old electric blanket over items you cannot remove from van,pumps,filters etc
3. Bring indoors hose & poles
4. Use rock salt on high traffic areas if water freezing on floor
5. Use a hot water system to heat your water to keep you working even if freezing
Using these tips has helped me to continue despite weather conditions ,and one more,, buy some snow boarding gloves!