How much do Dormer loft conversions cost on average? Bigger homes will almost always sell for more, and one of the main benefits of investing in a dormer loft conversion is the space that it can add to your home and in turn, the value that this will create. A dormer loft conversion maximises the entire loft space and can often be used to create an entire bedroom and en-suite bathroom, along with many other room ideas. A dormer loft conversion can also make for an ideal home office space, which can add value to your home and generate more interest, particularly after COVID19 with more people working from home and looking for a property with a suitable area for working.