But why?
Why do you want to cover up your radiators? Because they are ugly. So why not change the radiators? That way you could continue to hang up your washing on them! Well, that's what I did in my own home. These cast iron “Liberty” radiators are only a little more expensive than covers, although there is also the cost of installation not to mention disruption.
Alright, so maybe you don't want your front room to look like a laundry and a radiator cover will give you a shelf on which to display your porcelein pig collection.
But a radiator cabinet will absorb heat from the radiator, keeping it from getting into the room. Heat that you have paid for. Radiator covers do not improve the efficiency of your radiators. Many manufacturers make the ludicrous claim that the cabinet helps to convect the heat, pulling in cold air from ground level and expelling hot into the room from the top. This is patent nonsense.* The price of beauty
As I understand it, you don't like the look of your radiators and are willing to spend good money to hide them.
You are also willing to put lumps of MDF around your radiators, letting it absorb the heat that you are paying gas bills to generate. The deduction is elementary: you are prepared to buy beauty. You are a true aesthete. Art for art's sake should be your motto. So why is it that you, sensitive artistic soul, even consider the common or garden radiator covers? Oh, yes, if you buy one from B&Q or the Argos catalogue it will be cheap. Some even find the mass-produced monotonously idenitical look reasssuring. But wait. You wish to hide your radiators because they are not attractive. Have nothing in your house you do not know to be useful or believe to be beautiful, as William Morris once said. Radiators are useful. Our radiator covers are not useful but they are beautiful. The mass-produced radiator cover is neither useful nor beautiful. 
How much
Let's cut to the chase. How much will it cost you? Expect to pay £290-350 for a single cover, including measuring, staining, delivery, fitting and VAT. The price will come down a bit if you take more than one and go up or down a bit if your radiator is exceptionally large or tiny. The price for a painted MDF cover will cost slightly more than a timber-veneered version, believe it or not. To get a good paint finish on MDF requires many coats and hours of work. You can save a bit of money if you fitted the cover yourselves.
When we fit you radiator cover, we scribe it to the wall. That is to say, we cut out the shape of your skirting boards on the cover and we plane the back edge of the shelf so that it follows your wall, even if the wall is quite uneven. The end result is a snug fit with hardly any gaps around the edges. But we also paint your radiator. Not just paint it to match the colour of the radiator cabinet, we also add some graining effects.
Here you see a radiator that has already had an undercoat of emulsion. The next coat, here in shellac, is adding to the colour and creating streaks to mimic grain. Finally, there will be a coat of polyurethane varnish with colour added to match the colour even more closely.
Our radiator cabinets are absolutely made to measure. They are not simply adjustable or come in several sizes, they are made to fit your radiator exactly. We can accommodate tight corners, odd sizes, nearness of window sills and door facings, access for thermostats or electrical sockets. Because they are handmade and completely bespoke, our covers are not cheap. And, what's more, even the design is bespoke.
Bespoke designs?
Yes. We offer bespoke designs. Until recently we have not charged for designing something to go with your furniture
or the period of your house. However, this has proven to be business folly. The "Japanese" radiator cover, the "Art Deco" cabinet, and this one here have all been abandoned by the fickle customer. When we say we offer bespoke designs, we really mean that you can either come up with your own crazy design or fiddle about with some of our own minor details, such as the cut-outs in the slats. You can have no cut-outs or hearts or variations on hearts. You could have squares but we would rather you took circles; you can also have diamonds. I started to make up a set of drawings of the cut-out variations we offer. If I live to be very old, I may finish this tiny project. 
Mostly we use upside down hearts or "tulips". On the rare occasion the repertoire is enlarged, the reason is usually that someone has furniture or staircase spindles with cutouts that we are trying to match. You'll see more if you go to the gallery page. Meanwhile, it is worth pointing out that the height of the skirtings and the shape of the mouldings are made to mimick your own home's skirtingboards. Notice that the two radiator covers at the top of this page are very similar, but the size of the skirtings are quite different.Footnote
*Covering a radiator cuts down its heat output. We make radically different radiator covers to the mass produced variety. We pay little attention to the conventional designs of our competitors and try to make our covers look like art while allowing them to do their job. To start with, we leave your radiator as open to the room as possible. The average commercial cabinet grille is no more than 30% open and 70% screened, whereas ours are about 60% open and 40% screened. Other manufacturers make the ludicrous claim that by building up heat behind behind the screen the heat is convected through the top slit and shoots out into the room instead of rising to the ceiling, making the radiator work more efficiently. Rubbish. The heated air circulates much the same way with or without a cover, but the cover itself will absorb heat (and waste energy you are paying for). If manufacturers were really interested in preventing heat loss, they would coat the inside of their cabinets with a heat reflecting material. The DIY enthusiast might wish to stick an insulating foil on the reverse side of the top shelf (which absorbs by far the most heat). We offer to do this for you at a price of £15. We estimate that it will take at least ten years of use before this option is economically and environmentally sound.