big old house, £10 a day gas in winter, more if freezing
big modern house, £3.50 a day in winter.
Insulation is a wonderful thing.
Agree about checking the meters frequently and putting it in your diary or a document. You can also input them to your energy company online to avoid estimated bills (I do mine monthly).
The £pounds in a bill will vary by price changes and estimated readings as well as usage pattern, so are not much help.
A meter reading history records usage pattern, especially if you make a note of "warm" "cold" "very cold" "heating off" "ill at home, heating on 24hours" or whatever.
Your washer might use about 15p per wash so is not the culprit. Energy usage is almost all heating.
In summer, my gas is about half a cubic metre per day (about 25p) for hot water.
Tell us how many cubic metres of gas you have used since your last Actual (not estimated) meter reading.