Short answer
For an Irish winter, most people need a 13.5 tog duvet. Go to 15 tog if your bedroom drops below 13 degrees at night or you feel the cold; stay at 10.5 tog if you sleep in a modern, well-insulated home with the heating on. For summer, 4.5 to 7.5 tog. If you only want to buy one duvet, a 4-season set (a 4.5 tog summer layer and a 9 tog autumn layer that press-stud together into 13.5 tog) covers all of it.
Tog is a measure of how well a duvet holds heat in. The scale runs from about 1 tog (barely there) to 15 tog (the warmest sold for home use), and a higher number means a warmer duvet. It says nothing about weight, quality or filling, only insulation, which is why a light goose down duvet and a heavy polyester one can both be 13.5 tog.
The catch for Irish shoppers is that tog is a British measurement. Most duvets sold online in Ireland now come from Dutch and German suppliers, ours included, and they are labelled with a GSM filling weight or a warmth class instead. This guide gives you the tog numbers for each season, a conversion table so you can read a GSM or warmth-class label, and a way to choose based on how cold your bedroom actually is rather than what month it says on the calendar.
In this article
- What do the tog numbers mean?
- What tog duvet do I need for winter in Ireland?
- Which tog for your bedroom temperature (not the season)
- Tog vs GSM vs warmth class: the conversion table
- How 4-season duvets work (and why 4.5 + 9 = 13.5)
- Our duvets, translated into tog
- Couples who disagree, hot sleepers, children, students and older people
- Frequently asked questions
What do the tog numbers mean?
Five ratings cover almost everything on sale. Here is the scale, with the bedroom temperature each one suits.
| Tog | Warmth | Best for | Bedroom at night |
|---|---|---|---|
| 1 to 4.5 | Light | Summer, heatwaves, hot sleepers, children over 12 months | 20 degrees and above |
| 7.5 | Light to medium | Most Irish summer nights, late spring, early autumn | 18 to 21 degrees |
| 10.5 | Medium | Autumn and spring; winter in an A or B rated home with heating on | 16 to 19 degrees |
| 13.5 | Warm | Winter in most Irish homes, November to March | 13 to 16 degrees |
| 15 | Very warm | Unheated bedrooms, older houses, people who feel the cold, students | Below 13 degrees |
You will also see 12, 13 and 14 tog in shops, and 9 tog on the heavier half of 4-season sets. They sit exactly where you would expect between the numbers above.
What tog duvet do I need for winter in Ireland?
13.5 tog is the right answer for most Irish bedrooms, and the reason is the housing stock, not the weather. Winter nights here rarely fall much below freezing, but most Irish homes were built before modern insulation standards, and once the heating goes off at 10 or 11pm an upstairs bedroom in a C, D or E rated house drifts down to 13 to 15 degrees by 3am. That is 13.5 tog territory. In a newer A or B rated home that holds 18 degrees overnight, 13.5 tog will have you kicking the duvet off, and 10.5 tog is the better buy.
15 tog earns its place in three situations: a bedroom with no radiator or a single-glazed window, a house where the heating is never on overnight to keep the bill down, and anyone who simply feels the cold, which includes a lot of older people and most students in rented rooms. The difference between 13.5 and 15 is noticeable but not dramatic; if you are between the two, choose 13.5 and add a throw at the foot of the bed for the coldest weeks.
The duvet decides how warm the bed is; the cover decides how it feels when you get in. If the bed is still cold on contact with the right tog, the fix is the fabric rather than more tog: see our guide to brushed cotton vs flannelette vs teddy fleece for Irish winters.
Which tog for your bedroom temperature, not the season
The month is a poor guide because two Irish bedrooms in the same street can be 6 degrees apart at night. A cheap digital thermometer left on the bedside table for a week tells you what you actually need. Match the lowest reading to this table.
| Bedroom at 3am | Typical of | Tog if you run cold | Tog if you run hot |
|---|---|---|---|
| Below 12 degrees | Unheated rooms, old farmhouses, bedsits with no radiator | 15 | 13.5 |
| 12 to 15 degrees | Most pre-2000 Irish houses with heating off overnight | 13.5 or 15 | 10.5 or 13.5 |
| 16 to 18 degrees | Insulated homes, apartments with neighbours on all sides | 13.5 | 10.5 |
| 19 to 21 degrees | A-rated homes, heating on all night, summer | 10.5 | 7.5 |
| 22 degrees and above | Heatwave, attic rooms in July, very warm apartments | 7.5 | 4.5 or a sheet |
Damp makes a difference too. Irish air is humid all year, and a damp room feels a couple of degrees colder than the thermometer says. If the walls sweat in winter, round up.
Tog vs GSM vs warmth class: the conversion table
This is the part the other tog guides skip. A duvet made in the Netherlands or Germany is usually labelled one of two ways. GSM is the weight of filling per square metre, so a 400 GSM duvet has 400 grams of fibre in every square metre. Warmth class is a 1 to 4 scale used on our Primaviera Deluxe and Dreamhouse ranges, where class 1 is the warmest winter duvet and class 4 is the lightest summer one. Neither is a tog rating, but for synthetic hollowfibre fillings they convert closely enough to shop with confidence.
| Tog (UK and Ireland) | GSM (synthetic filling) | Warmth class (NL, DE) | Season |
|---|---|---|---|
| 4.5 | 150 to 250 | Class 4 (light) | Summer |
| 7.5 | 300 | Class 3 (medium) | Spring and autumn |
| 10.5 | 400 | Class 2 to 3 | All year in a heated home |
| 13.5 | 500 to 550 | Class 1 to 2 (warm) | Winter |
| 15 | 600 and above | Class 1 (extra warm) | Deep winter, unheated rooms |
Three cautions. The GSM column is for hollowfibre and microfibre; feather, down and wool insulate differently per gram, so a 300 GSM down duvet is warmer than a 300 GSM polyester one. Some German brands number their warmth classes the other way round (1 lightest, 5 warmest), so check whether the label calls class 1 "Sommer" or "Winter". And a cover fabric changes how a duvet feels: percale cotton sleeps cooler than micropercale polyester at the same GSM.
How 4-season duvets work (and why 4.5 + 9 = 13.5)
A 4-season, or all-seasons, duvet is two duvets sold as one. The thin layer is around 4.5 tog and does summer on its own. The medium layer is around 9 tog and does spring and autumn. Fasten them together with the press studs along the edge and you have a 13.5 tog winter duvet. Tog values add up, which is the only bit of maths in bedding that works exactly as you would hope.
For an Irish home this is usually the smartest purchase, for three reasons. You buy one duvet instead of two or three. You never have to guess the season, because on a cold May night you use the two layers and on a mild December one you drop to the thick layer alone. And storage is easy: the layer you are not using fits flat under the mattress or in a drawer, which matters in a two-bed apartment with no hot press.
The combination maths, in GSM
Our Micro Touch 4-season duvet is a 200 GSM summer layer and a 300 GSM autumn layer. Alone, that is roughly 4.5 tog and 7.5 tog. Studded together it is 500 GSM, or about 13.5 tog. Three duvets for the price of one, and the only one of the three you have to store is the one you are not sleeping under.
Our duvets, translated into tog
None of our duvets carries a tog label, because they are made in the Netherlands, so here is each one with its GSM or warmth class and the tog it works out to. All are synthetic, hypoallergenic, machine washable at 40 degrees and come in EU sizes that fit Irish beds (see our Irish bed sizes guide for the fit). Stock changes weekly, so the sizes shown on each product page are the ones available today, and we are adding more duvets and Lazy Duvet designs to the range, so the collections are worth a look for the latest arrivals.
| Duvet | Filling and cover | Label says | Tog equivalent | Best for | From |
|---|---|---|---|---|---|
| Sleeptime Micro Touch 4-Season | Hollowfibre, micropercale cover, press studs | 200 + 300 GSM | 4.5, 7.5 or 13.5 | One duvet for the whole year in any Irish home | €39.95 |
| Sleeptime Micro Touch Lightweight | Hollowfibre, micropercale cover, banded quilting | 400 GSM | About 10.5 | Year-round in a heated or A-rated home; spring and autumn elsewhere | €24.95 |
| Primaviera Deluxe Percale Cotton Touch 4-Season | ECODOWN siliconised hollowfibre, 233 thread count percale cotton cover | Class 4 + class 3 = class 1 | 4.5, 9 or 13.5 | The hotel feel: crisp cotton, all year, sleeps cooler than polyester covers | €109.95 |
| Primaviera Deluxe Percale Cotton Touch Lightweight | ECODOWN hollowfibre, percale cotton cover, carre stitching | 400 GSM | About 10.5 | Hot sleepers who want a cotton cover and one duvet all year | €59.95 |
| Dreamhouse Bali Bamboo Touch | Hollowfibre, bamboo-touch cover, trapezium stitching | Warmth class 2 | About 10.5 to 13.5 | Autumn to spring; moisture-wicking cover for sweaty sleepers | €24.95 |
| Sleeptime All-in-One Lazy Duvet | Cover built in; microfibre, velvet, teddy fleece or percale cotton finish | Not stated | Light to medium, about 7.5 | Spring, summer and autumn; heated rooms in winter; kids' and guest beds. Teddy fleece version is the warmest | €29.95 |
200 GSM summer layer, 300 GSM autumn layer, press studs to join them for winter. Hypoallergenic, dust mite resistant, 40 degree wash. Single to 240 x 220 king. Sizes shown are subject to availability.
400 GSM single-layer hollowfibre with banded quilting so the filling stays put. The right weight for an A or B rated home, an apartment, or anyone who wakes up too warm under 13.5 tog. Sizes shown are subject to availability.
233 thread count percale cotton cover over ECODOWN siliconised hollowfibre. Crisp, cool to the touch and quick-drying; the closest a synthetic duvet gets to the hotel feel. Sizes shown are subject to availability.
Couples who disagree, hot sleepers, children, students and older people
One of you is always too hot
The German and Dutch answer is two single duvets on a double bed, one 10.5 tog and one 13.5 tog, and it works. Two 140 x 200 duvets side by side cover a 140 or 160 cm mattress with no gap, each person gets their own tog, and nobody steals the covers. The compromise for anyone who finds two duvets untidy is a 4-season set: the cold sleeper uses both layers, the warm sleeper borrows the 9 tog layer, and in spring you swap back.
You sleep hot whatever the season
Go one step down the table from your bedroom temperature and choose a percale cotton or bamboo-touch cover over polyester micropercale. Cover fabric affects how sweaty you feel more than most people expect; the filling only affects how warm you are.
Children
Babies under 12 months should not have a duvet at all; use a sleeping bag or cellular blankets and follow the HSE safe sleep advice. From 12 months to around 4 years, keep it light, at 4.5 tog or under, which is why the 200 GSM summer layer of a 4-season single is a sensible first duvet for a toddler bed. School-age children usually do well on 7.5 to 10.5 tog; they run warmer than adults and complain less about cold than about sweat.
Students and older people: why a Lazy Duvet makes sense
A Lazy Duvet is a duvet with the cover permanently sewn on. That one change solves the two problems that come up most in student rooms and in older people's homes.
- Students. One item to buy instead of a duvet plus a cover, it goes in a shared washing machine as one piece, tumble dries on low and is back on the bed the same evening, and at single size it costs less than most duvet-and-cover combinations. It also survives the end-of-year move because there is nothing to lose.
- Older people and anyone with limited mobility. Changing a duvet cover is the job that gets skipped when shoulders, wrists or backs are sore. With the cover built in there is no wrestling, no corners to find, and the whole thing is lighter to lift than a 13.5 tog duvet inside a cotton cover. For anyone who cares for a parent, pairing a Lazy Duvet with a waterproof mattress protector means the entire bed can be stripped, washed and remade in one cycle.
- Guest rooms and children. The same logic applies: quick to wash, quick to dry, no spare covers to store.
On warmth, a Lazy Duvet sits at the light-to-medium end of the scale, roughly 7.5 tog, so it is right for a heated room, a student flat with the radiator on, or spring to autumn anywhere. For a colder room choose the teddy fleece version, which is the warmest in the range, and add a throw or blanket in the coldest weeks; for an unheated bedroom, a 13.5 tog duvet is still the better tool.
Duvet and cover sewn into one piece that goes in the machine and back on the bed the same day. Now in microfibre, velvet, teddy fleece (the warmest of the range) and 100% cotton percale, in single, double and king. Designs and sizes shown are subject to availability.
Frequently asked questions
Is 13.5 tog warm enough for winter?
For most Irish bedrooms, yes. 13.5 tog suits a room that sits between 13 and 16 degrees overnight, which covers the majority of Irish homes once the heating goes off. If your room drops below 13 degrees, or you are cold under 13.5 tog with the window closed, move up to 15 tog.
Which is better, 10.5 tog or 13.5 tog?
10.5 tog is a year-round weight for a home that stays at 16 degrees or above overnight; 13.5 tog is a true winter duvet for a room that gets colder than that. If you are choosing one duvet for an older Irish house, 13.5. If you are choosing one for an A-rated new build or a warm apartment, 10.5.
Is there much difference between 13.5 and 15 tog?
The difference is real but small, roughly the warmth of a light blanket. Choose 15 tog for an unheated room or if you feel the cold; choose 13.5 tog and add a throw if you are in between, because a 15 tog duvet is too warm for the same room in October and March.
Is a 7.5 tog duvet too warm for summer?
Not in Ireland. Summer nights here average 11 to 14 degrees outdoors and most bedrooms stay under 20, so 7.5 tog is comfortable for the majority of people from May to September. Switch to 4.5 tog only during a heatwave, in an attic room, or if you are a very hot sleeper.
What tog do hotels use?
Most hotels use a 10.5 tog duvet, or the continental equivalent of around 400 GSM, because their rooms are heated to a constant 19 to 21 degrees. A 10.5 tog duvet with a percale cotton cover is the closest match at home, provided your bedroom is as warm as a hotel's; in a typical Irish house you will want 13.5 tog to get the same feeling.
How do I convert GSM to tog?
For synthetic hollowfibre duvets, 200 GSM is about 4.5 tog, 300 GSM about 7.5 tog, 400 GSM about 10.5 tog, 500 GSM about 13.5 tog and 600 GSM or more about 15 tog. Natural fillings such as down and wool are warmer per gram, so the same GSM gives a higher tog.
Are Lazy Duvets warm enough for an Irish winter?
In a heated bedroom, yes. A Lazy Duvet is a light-to-medium weight, about 7.5 tog, so it suits a room that stays at 16 degrees or above overnight, which covers most apartments, student accommodation and modern homes. In a colder room choose the teddy fleece Lazy Duvet, the warmest in the range, and keep a throw on the bed for January. In an unheated room, a 13.5 tog duvet remains the right choice.
Found your tog? Now pick the duvet
4-season sets, 400 GSM year-round duvets and all-in-one Lazy Duvets, made in the Netherlands, in sizes that fit Irish beds, shipped from Ireland.
Shop duvets → Shop Lazy Duvets →Not sure which weight suits your room? Email customercare@beddingandblankets.com with your bedroom's overnight temperature and we will tell you which duvet to buy.
