What a tent's waterproof rating is
The rating in millimetres, the hydrostatic head, is the height of a column of water a fabric holds back before water comes through, tested to BS EN ISO 811. The higher the number, the harder the rain has to push. A tent usually gives more than one figure: one for the flysheet, the skin that takes the rain, and a higher one for the groundsheet, because you kneel and lie on it. Each tent here is filed in one band by its flysheet's rating, the figure for the fabric that takes the rain. Where a maker gives only a groundsheet figure, that is used. Every figure the maker gives is on the product page.
The ranges By Waterproof Rating
- Waterproof to 2,000mm: a flysheet rated under 2,500mm. For summer showers and dry weekends. See waterproof to 2,000mm.
- Waterproof to 3,000mm: a flysheet rated from 2,500mm to 4,999mm. For proper British rain. See waterproof to 3,000mm.
- Waterproof 5,000mm and over: a flysheet rated 5,000mm or more, for downpours, wind-driven rain and the hills. See waterproof 5,000mm and over.
Which rating you need for British rain
Around 3,000mm on the flysheet is generally regarded as dependable for camping in Britain, heavy and long spells of rain included. About 1,500 to 2,000mm suits summer and dry weekends, and below about 1,500mm a tent is a risk in heavy rain. More than 3,000mm is worth having for long trips, exposed hills and rain driven by the wind, which presses water into the fabric harder than rain falling straight down.
The number is not everything. Taped seams, a taut pitch and the guy lines pegged out keep you drier than a big figure on a badly pitched tent, and a double layer keeps condensation off you, which a rating does nothing about.
Questions people ask about waterproof ratings
Why is the groundsheet rated higher than the flysheet?
Because you kneel and lie on it, and your weight pushes water up through the fabric. The Archeos 3-person tent here, for example, has a PU2000mm flysheet and a PU3000mm floor, so it is in the 2,000mm band.
Does a higher rating mean a better tent?
Not on its own. A well-made tent with taped seams at 3,000mm will keep you drier than a poorly made one with a bigger number. Match the rating to your trips: summer weekends, a week on a campsite in Britain, or the hills.
How long does delivery take?
Delivery is included in every price and tracked to your door. Each product page says when that tent usually arrives, so check it before ordering for a set date.
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