Introduction
Depending on your seating / bed option you may have all your van cushions already. For my van I needed to sort all the cushions due to how the rear passenger seat and bedding boards were made. This section offers some advice if you are thinking of making your own, replacing old cushions and covers or at least having to measure them up and get them made.
Buying
I ended up buying my cushions. Without a good sewing machine and time! it was going to be pretty difficult to home make. A set of 4 cushions 3 at 1.2m x 0.5m (for the seat and to cover one of the back bed boards) and 1 at 1.2m x 0.4m (for the rear back bed board), enough 4" high density foam, sufficient material to cover plus velcro for attachment cost £160.00 which I reckon made it well worth getting someone else to do it. I also got them to add a knee role to the bench seat cushion (basically half of a cyclindrical roll) to provide comfort and support beneath the knees when passengers are travelling in the back.
Making
With time and the inclination I reckon it would be possible to make covers for your cushions. The material would need to be pretty hard wearing however, meaning you might need a more heavy duty sewing machine, thread and needles. Purpose cut foam can be bought reasonably easily approx. £10 for 1m2. Remember you need dense enough foam for seating and sleeping - not too firm but firm enough.
Replacing Cushion Foam and Covers
A common issue is the need to replace cushion foam and/or the cushion covers. Either you've bought a campervan which needs the foam and covers replaced or hopefully you've got so much use out of your own campervan conversion and now it is time to update the furnishings.
As with making the cushions there is a difference between what works for sitting and sleeping when parked and what is needed for sitting when driving. Preferably a pretty dense and firm foam (although not necessarily thick) is what you will have. As detailed above I went for 4" but it's definitely worth being able to test the foam in person to be sure.
So, seat foam is likely to lose its firmness long before your campervan should give up the ghost. Usually, the foam starts to compress, leaving very little padding between you and the seat frame. Over time cushion covers get a lot of wear and tear and the odd stain or two!! If you fitted your own covers in the first place you hopefully picked a material consummate to the use the campervan was going to have. My cushions have a fairly rough time with wet and muddy kit often ending up on them so I went for a compromise between hard wear and comfort.
There are a number of solutions depending on your preference, budget and whether you want to replace the cushions and covers yourself or pay someone else. Any good upholstery company would also probably do any of the following for you at reasonable cost.
Introduction
When making cushions the covers are the bit that take time and skill. It is a good idea to get good well fitted covers as they protect the foam and give maximum convert. A pretty good option for quickly and cheaply updating your campervan cushions though is to fit additional loose covers. A throw or rug would be a super quick option but likely to get annoying when it keeps slipping off. Zipped or popper button loose covers can smarten up a campervan pretty quickly they also help to protect the original cushions and can be easily taken off and washed.
Cover Fabrics and Finishes
Choice of material is a very individual thing but you will want something comfy and reasonably hard wearing. Although, unlike the cab seating, it is nice to have the interior seating in a softer material. Many motorhomes have soft velour and velvet style fabrics. I wanted something slightly more robust and have a good green cord for my cushion covers. Go into any upholstery store and they will have a whole range of materials and should be happy to discuss the best option for what you want. If you are not too fussy about colour or pattern, chances are they will also have some off cuts and sale fabrics which can be pretty cheap.
Finally you can make the interior furnishings as fancy as you like with a while range of finishes such as piping, ruches and cords. Professional upholsterers should be able to do all of these but it will cost you more.
One of the simplest aspects of converting your campervan is the bedding (the mattress is discussed above under cushions). Basically standard sheets, covers and pillows are fine and can be folded or if your are feeling keen, altered, to fit. These can be bought pretty cheaply in the usual stores. You probably don't want anything fancy just plenty to keep you comfy and warm. It is an idea to either have a dedicated storage space or a bag in which to store the bedding when not in use - you really want to keep this stuff clean and dry! To add a little bit more cushioning to the mattress I have a cheap duvet which sits on top of the seat cushions which make up the bed but under the sheet which holds it in place. This helps to smooth over the joins between the cushions, making a comfier sleeping surface and also adds to the warmth.