To cover or not to cover?

One of the most often used solutions for transferring heat the length of a boat is to employ a back boiler with radiators. A slightly fancier and more modern alternative a combi boiler. Without getting into the specifics of plumbing, because we aren't plumbers, I thought it might be interesting to discuss the two choices for radiators, being to cover or not to cover.

In a house when a radiator cover is created it is almost always done so in soft wood and mrMDF (moisture resistant MDF). The framing being a solid soft wood and the inside is often an intricately cut grill of mrMDF inside. Although this is a very popular way of doing it, there are some things that are worth considering. First of all a wood grill holds on to the heat in a situation where we want the heat transferring as quickly as possible.

“Even the most thermally conductive stick of wood transfers heat about 500 times more slowly than steel. This slow rate of heat transfer makes wood a good heat insulator, right up there with insulating brick and comparable to rock wool and fibreglass insulation". 1

So good for holding heat but not great for letting into your boat in the first instance. It's not a cut and dried case either way! If you're sure that a cover is what you want, consider a metal grill. Covering a radiator can not only tidy appearance it can also give you some additional shelf space, which can be a bonus if you want a convenient space for a book or a glass water near the bed.

So why would anyone want an uncovered radiator? Well, sometimes it's for better heat transference as above, and sometimes it's purely aesthetic. There are some absolutely lovely “new old school” style radiators out there and coupling that with a bit of bent copper pipe, can be quite a stunning look. If you choose to go this route do pay attention to the efficiency ratings as often the lower end of the price range in this style, sacrifice efficiency for looks. There are good ones out there though, so do some research.


If you care to google it, there's quite a lot of debate online, as to if covered is better than uncovered, mainly what it comes down to in the end is personal choice. Which do you prefer?