a firmer support for cushions
Foam blocks are usually used in making chair cushions as bases or thinner ones can be used to make cushion inserts. These are used more in upholstery but are great for garden furniture. They are made from Polyurethane.
This was invented by a German chemist called Otto Bayer, he along with a few others invented the foam in the late 1930's.
It is a kind of polymer made up of carbon units joined by urethane links.
This is used widely in seating, insulation panels, wheels and tyres, sealants and carpet underlay to name but a few.
These kind of cushion fillings are really good for the bases of chairs and are usually put inside boxed cushion designs. Their rigid nature makes them ideal and give extra support that a cushion base needs. If a soft base is needed then the foam can be covered in wadding to make it softer.
This filling is used more in garden cushions and would be good when making a cushioned seating pad for picnics.
When making cushion covers for these type of seats the cover needs to fit the foam shape exactly. Usually the foam insert needs to be folded slightly to get it through the gap left for the fastening. As the block springs back into shape it will slightly stretch the material giving a tight fitting appearance.
Foam can also be used inside scatter cushions either in blocks or as foam pieces. A cushion pad would be needed if little pieces are to be used so the cover can be removed for cleaning without the insides spilling out.
If using foam pieces these can get a little lumpy and will probably need to be plumped up to keep it pliable. Over time the compression of the foam will cause it to break down so eventually it may need replacing.
This is usually a cheaper type of
cushion filling although durable. It can also be used if the cushion being made is not going to have any fastenings in it as it will wash well as part of the cushion.
If you are using foam to put inside your cushions then make sure it is fire retardant. Sprays can be bought to use if you are unsure and is important if the cushions are going to be used inside possible near a heat source.