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400 x 800mm Horizontal Radiators
Looking for a horizontal radiator around 400mm high and 800mm wide? We have 3 horizontal radiators in stock in this size from Ethiant, priced from £164.32 to £307.84 with heat outputs from 2,517 to 4,783 BTU/hr (ΔT50). Actual dimensions in this group run from 400–400mm high and 830–830mm wide; the exact size, pipe centres and output of each model are on its product page.
A 400 x 800 horizontal radiator is the size most UK homes were built around, so it usually replaces an existing radiator without moving the pipework, and the highest-output models here will heat a typical living room or a large bedroom. Every model is in stock for free delivery to mainland England and Wales, and each product page shows the certified heat output for every size so you can match it to your room with our BTU calculator.
400 x 800mm Horizontal Radiators in stock
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Traditional 3 Column Horizontal Radiators 400 Height
Price range: £104.83 through £286.00 Select options This product has multiple variants. The options may be chosen on the product page -
Traditional 4 Column Horizontal Radiators 400 Height
Price range: £112.32 through £338.99 Select options This product has multiple variants. The options may be chosen on the product page -
Traditional 6 Column Horizontal Radiators 400 Height
Price range: £344.99 through £455.31 Select options This product has multiple variants. The options may be chosen on the product page
Compare every 400 x 800mm horizontal radiator in stock
| Model | Finishes | Sizes in this group | Heat output (BTU/hr, ΔT50) | From |
|---|---|---|---|---|
| Traditional 3 Column Horizontal Radiators 400 Height | White | 400 × 830mm | 2,517 | £164.32 |
| Traditional 4 Column Horizontal Radiators 400 Height | White | 400 × 830mm | 3,166 | £231 |
| Traditional 6 Column Horizontal Radiators 400 Height | White | 400 × 830mm | 4,783 | £307.84 |
Questions about 400 x 800mm horizontal radiators
How much heat does a 400 x 800mm horizontal radiator give out?
Between 2,517 and 4,783 BTU/hr at ΔT50 across the 3 models on this page. The highest output here is the Traditional 6 Column Horizontal Radiators 400 Height at 4,783 BTU/hr (1,402 W). All figures are the manufacturers’ certified outputs to EN 442, quoted at ΔT50 — the UK standard for sizing central-heating radiators.
Which 400 x 800mm horizontal radiator is the best value for heat?
On heat per pound it is the Traditional 6 Column Horizontal Radiators 400 Height: 4,783 BTU/hr for £307.84, about 16 BTU for every £1. The cheapest model on the page starts at £164.32.
What size room will it heat?
It depends on the model — the range on this page runs from a bedroom, home office or small kitchen at 2,517 BTU/hr up to a typical living room or a large bedroom at 4,783 BTU/hr. A well-insulated modern room needs far less than an older one with single glazing and an outside wall, so use our BTU calculator with your room’s measurements before you choose.
What colours and finishes are available?
In this group we have 3 in white. Colour is chosen as a finish option on the product page.
What else do I need to fit it?
A pair of radiator valves (a thermostatic set is the usual choice) — see our valves and accessories. Wall brackets are supplied with every radiator, and column radiators in this group can be fitted with feet where the wall will not take the full weight. Delivery to mainland England and Wales is free.
Related sizes and ranges
Back to Radiators by size.