What is that under your arse? It's foam, of course. But it is the right type of foam? And did you ever imagine there could be a right and a wrong type of foam? Well, there is. I will go into the whole shebang in quite a bit more detail (but not too much detail, honestly) in my new book, The Camper Van Bible, so this is just a taster of the delights to come...
Let's begin with the day you decide to get some more foam for the cushions in your van. It's easy, right? You buy some foam, have it cut to size, sew some new covers and Bob is your uncle...wrong!
Firstly, you need to think about what your cushions are to be used for predominantly. Are they to be used as seating or are they to be used as bedding? This is relevant as some foam is better suited to sleeping than sitting, while other foam is better for sitting...
Foam comes in grades with a load of numbers like 3 INCH V 38 / 200 or 4 INCH R 40 / 180.
What these mean to you and how they will affect your comfort depends on how far you read on and whether or not you have glazed over yet. But stick with it... it gets better...
Foam is graded by FOAM TYPE, DENSITY, HARDNESS and VOLUME. In the first set of numbers above it is graded thus:
VOLUME (3 INCH), FOAM TYPE (R), DENSITY (38), HARDNESS (200)
FOAM TYPE is the basic name for any particular type of foam. It is the bit that comes after INCH in the ratings above. The grades are:
V is for foam that is ‘heavy domestic and contract quality’. A quality foam that is best suited for sitting and seat cushions and will last well. Generally 30% cheaper than REFLEX and better suited to sitting than sleeping.
R is for Reflex, a brand name. This is a very high quality latex foam that will retain its properties over time. The best quality for sleeping.
Other grades of foam are:
CMHR is for ‘Combustion Modified High Resilience Foam’ that includes a lot of melamine for flame retardancy. It can tend to powder over time and can retain moisture so not recommended for camper vans.
RECON is reconditioned foam. It is made up from all the off cuts. It is generally poor wearing, very heavy and not much use to anyone, although it is cheap. Avoid.
Still with us? Okay, moving on.
FOAM DENSITY is the weight of the foam in KILOGRAMMES PER CUBIC METRE. In the foam ratings it comes after the TYPE of foam. The higher the number the higher the density. A high density foam will last longer and be of better quality. Expect to see Density of around 38 – 40 for a decent foam. This is the part of the rating that comes after the R or V.
HARDNESS is measured in NEWTONS. It’s all about the science here so I shall skip that and say that the hardness is all about the comfort. Typical foams for campers come in at any where between 135-200 Newtons, depending on the comfort required, with the lower number being less firm than higher numbers.
VOLUME is basically the thickness of the foam, with increased volume offering you more support.
However, after a certain point volume is pointless, as a dense foam can have the same support at 3 inches thick as at 4 inches thick, depending on how you use it.
THE RULE FOR CHOOSING FOAM:
If you are sitting more than sleeping, use a high density V grade foam. If it’s less firm, go for extra thickness. V40 / 200 at 3 inches is a good bet for camper van cushions.
If you are sleeping more than sitting, use a thicker, but less firm REFLEX foam. Try something like a R38 / 150 at 5 inches for a cosy night.
Too much detail? Until the time comes to look for a mattress, maybe.
The Camper Van Bible goes on sale on June 2nd, with signed copies available from martindorey.com