heating review · November to February
Where the heat goes
You sent me the meter readings, the thermostat log, and the survey the installer left behind. This is what they say together. A chart has no words to select, so click one and the comment lands on the whole picture — say which number you want and I will put it in the next version. The last section asks which measure to pay for first.
Five winters
The meter has November-to-March totals back to 2021. This winter is the lowest of the five, and it is also the mildest, which is the reason for everything below.
winter, meter 2021-22, 11840 2022-23, 10920 2023-24, 11510 2024-25, 12260 2025-26, 10480
This winter, week by week
Gas use climbed until the week before Christmas and then fell away faster than the weather did. The draught-proofing went in on 12 January, which is the week the line turns.
week, meter 2025-11-17, 441 2025-11-24, 470 2025-12-01, 512 2025-12-08, 538 2025-12-15, 561 2025-12-22, 604 2025-12-29, 588 2026-01-05, 597 2026-01-12, 542 2026-01-19, 498
One of those weeks is not comparable: the boiler was serviced on 8 December, so that week starts a day late and reads low for a reason the weather cannot explain.
What the gas is doing
The meter cannot tell heating from hot water, so this split comes from the boiler's own hour counters. Hot water and cooking barely move across the winter; the whole of the seasonal swing is space heating.
month, space heating, hot water, cooking Nov, 1180, 320, 60 Dec, 1890, 350, 95 Jan, 1720, 340, 70 Feb, 1240, 315, 60
Where it leaves
These five are the installer's survey, in watts lost at a 20°C difference between inside and out. The bay window is a third of the five together.
element, loss single-glazed bay window, 410 uninsulated loft hatch, 265 suspended timber floor, 240 front door and letterbox, 155 chimney with no cap, 120
Against the weather
Every week sits at its own average outside temperature, so a colder winter
cannot be mistaken for a leakier house. The two runs are the same house six
weeks apart: the second sits about
outside average, before, after 2.1, 604, 3.0, 588, 3.4, 561, 4.2, 538, 5.0, 512, 6.1, 470, 2.6, , 542 3.8, , 498 5.2, , 470 6.4, , 449
Which measure should be booked first?
The three are independent, and doing all of them this year needs the floor to come up while the room is being used. Pick the one to book now; the click records it and I will get the date from whichever firm you name.
265 watts for the cheapest job on the list, and nothing has to be moved to do it. It is the smallest saving of the three and the only one that can happen next week.
The largest single loss, and the room nobody sits in during January. The quote is for an internal panel, so the sash and the outside of the house are untouched.
240 watts, and the disruption of the three. It is worth doing before the floor is refinished rather than after, which is the argument for taking it now instead of next winter.