An 80mm cylinder jacket is one of the cheapest ways an oil home cuts heat loss. Here's the rough cost, the real saving, and how to fit one yourself.
By MyOil Editor ·
If you have an older copper hot-water cylinder with a thin or missing jacket, fitting a proper 80mm lagging jacket is close to a no-brainer. It is cheap, you can do it yourself in twenty minutes, and it quietly cuts the heat your cylinder leaks all day, every day. For an oil-heated home that pays to warm that water, less standing loss means your boiler runs a little less hard.
It will not transform your bills on its own. But pound for pound, very few things give you a faster payback.
A hot-water cylinder is basically a tank of heat sitting in a hot press. Without good insulation, it sheds that heat into the room round the clock. Your boiler then fires more often to top the temperature back up, burning oil to replace warmth that simply drifted away.
The SEAI (Sustainable Energy Authority of Ireland) lists the hot-water cylinder jacket among the simplest, lowest-cost energy savers a household can make. The key numbers:
So the big wins are for older cylinders that are either bare copper, or wrapped in a thin, tired jacket you can squash flat with one finger.
An 80mm jacket is one of the cheapest upgrades in the house, usually a small amount from any hardware shop or builders' merchant. There is no installer needed.
The saving is modest in absolute terms but the payback is quick, often inside a heating season for an older bare cylinder. Think of it as money you stop wasting rather than a dramatic cut. Combined with a few other cheap measures, it adds up across the year.
Where it really matters: if you heat water with the oil boiler (rather than only an immersion in summer), every bit of standing loss is oil you paid for. Keeping that heat in the tank means fewer reheats.
This is a genuine DIY job, no tools, no gas, no electrics touched.
That is it. No mess, and you will feel the difference, the hot press stays cooler because less heat is escaping.
A jacket works best alongside a couple of other low-cost measures:
For more of these low-spend upgrades that suit an oil boiler and cylinder, see our gadgets and cheap-saver guides.
Insulation jobs like this reduce demand, but they do not change the single biggest worry for most oil households: not knowing how much is left in the tank and the dread of running dry. Cutting standing loss helps your oil last a little longer between fills, which is one more reason to do it.
To stop guessing your tank level, you can see when you'll run out, and you can set a price-drop alert so you are buying on your terms. When it is time to top up, compare local prices by county.
Go and feel your hot press. If it is warm and your cylinder jacket is thin, missing, or squashable, an 80mm jacket is the cheapest twenty-minute job you will do all year. Buy the right size, wrap it snug, and lag the nearby pipes while you are at it.
Set a price-drop alert and we'll email you when oil gets cheaper in your county.
Set a price-drop alert →Pop in your tank and last fill, and we'll estimate how many days you've got left.
See when you'll run out →Lag the hot pipes between your oil boiler and cylinder so the heat reaches your taps, not the hot press. Cost per metre, what to buy, and how to do it.
Read →An honest look at radiator foil for Irish homes: where it saves, where it won't, and how much you'd really notice on your oil bill.
Read →Cheap fixes for doors, windows and unused chimneys that stop draughts and save heating oil. DIY vs fitted, with rough savings for Irish homes.
Read →Tell us your county and we'll watch the price by the fill, not the cent. Add your tank and we'll tell you when you'll run out, and nudge you in good time to order.