I’m planning to get my flat’s ancient central heating replaced with a new boiler, radiators, etc. The plumber who came by this evening to look at things and take notes to prepare an estimate reckoned it was best for the new radiators to go close to rooms’ doors where possible, not under their windows, as the current radiators generally are.

I’d not heard of this before, I generally expect radiators to be under the windows. Is it more common now for radiators to be located next to doors? Where are yours?

Ours are under the windows. Not necessarily the best place for retaining heat, but best for room layout. You don’t want to be putting furniture in from of the rads, so unless you have very big rooms the best place for them is where you don’t put furniture, ie, windows. And, if the door is in the corner, doors.

How draughty are your windows?

Under the windows…something to do with air flow…I don’t understand it and can’t be arsed to Google it.

You don’t want to be putting furniture in from of the rads

Plumber said that was also a reason for having them by the doors. :-/

Traditionally under windows to stop getting hot and cold spots in the room, convection currents and all that.
Having said that none of the rads in my house are under rads and I’ve never noticed any issues with uneven heat distribution. Probably cos its a Victorian house and always bloody cold.

All doors in middle of your house damn near it i bet ?

Easier/shorter pipe runs for him , less disruption for you etc etc

Fwiw previous owner here put all his rads by doors and all ground floor rads were within 8 ft of each other……. Back to back on walls save a few quid on copper and fittings

I moved em under windows when i moved in as doors didnt open fully , they were in stupid places and i was swapping them for more efficient units that werent stained with cigarette smoke.

What I love in most houses with rads under the windows is the curtains that are pulled and over the top of the rads. You’d be amazed how inefficient they are heating the sash of a (single glazed) window.

Under the windows to make sure convection current circulates round the room the right way, but make sure curtains are behind them.

Another reason for under the windows is that the wall above a radiator tends to get stained.

Convection staining.

The plumber just wants an easy life. Get rid of him and find one who knows why you put rads under windows.

Ask to see his het loss calculations

Studied civil engineering at college for a while, always told you put rads on the coldest wall.

your plumber is lazy and wants the easiest fit possible.
coldest area of room (in conventional hoese build) will be under windows, cold air sinks by putting you rads under windows the heat from the rad is pushed up and out into the room and then sinks back down to the flow >>convection<<.
If the windows are shut airflow around doors is a draft and not convection, shut the door and no draft / no heat exchange. take his argument to the ultimate and you would only fit 1 rad in the house and leave all doors open.
Also avoid micro bore pipe (its cack low flow rates / prone to silting), get a proper system full size pipes / rads under windows soldered joints. If he wont quote for this go elsewhere, anything else is false economy.

nwilko – why would you want a system with soldered pipework?

your plumber is lazy and wants the easiest fit possible.

Except that it’ll be a drop pipe system with the pipes coming down from a largely empty loft, so there’s not much difference where the pipes come down.

Annoyingly two rooms have long curtains that do/will obscure radiators. And yes I am aware that this is within my power to sort out, but the rate at which I address such things is pitifully slow.